The paper presents the author's view on digital photography of caves, based on experience gathered in the last five years, till 2004. It begins with an outline of pre-digital, traditional cave photography as practiced from the 1960's till the end of 1990's. A description of digital photography, 1999-2004, comes next, followed by chapters on technical topics such as resolution, colour temperature, illumination and equipment. Presentation of pictures, especially on the Internet, and genre photography in caves are discussed at the end of the paper. The text is illustrated with 31 pictures, taken in the caves of Slovenia, southern Adriatic, northern Africa and southern Pacific.
Slovenia is a small European country, situated at the
northeastern rim of the Adriatic Sea. It borders Italy, Austria,
Hungary and Croatia. There are some 2 million inhabitants across 21,000
square kilometers (8,000 square miles); 44 % is covered by karst area
with over 8,000 caves and potholes. The plain, stretching from northeast of
Triest, on the coast, to the Vremščica Mountain, is the original site
of karst research, beginning with the discovery of inner parts of
Postojnska jama cave in 1818. Cave photography followed at
fin-de-siecle and, since then, good cave pictures and good cave
photographers have not been in short supply. Some of the great
photographers, Bogumil Brinšek (pre-WWI), Franci Bar (mid-1900's) and
Tomaž Planina (late 1900's), have all been members of the Ljubljana
speleo group (www.speleo.net), which also happens to be my home team.
This paper offers a personal (my underground nickname is Klok) case study in the field of cave photography - the brands and names of cameras, flashguns etc. are given without any advertising intentions and some other photographic equipment would of course serve the purpose well. A very similar text in Slovenian has been published in Glas podzemlja magazine, april 2004, pp. 27 - 52 (ISSN 1581-8942, http://www.speleo.net/dzrjl). This paper, with screen-size pictures in colour and live links, is also available on the world wide web, at the URL http://www.jamarska-zveza.si/izobrazevanje/nj_2004/pj.
I would like to express my gratitude to the members of Ljubljana speleo club (Društvo za raziskovanje jam Ljubljana) and to all the others (Andreja, Barbara, Bojana, Jana, Lucija, Marjeta and Nadja have shown particularly great courage), who have helped at the scene of the pictures and contributed to the experience described in the paper. A short explanation for non-native readers: jama in Slovenian stands for cave, brezno is a shaft or pit and Laze is a name for 23 villages in Slovenia; the most famous Laze in caving context, often mentioned here, is situated in Inner Carniola, at the northeastern rim of Planinsko polje, halfway between Vienna and Florence. It is a caver's Eldorado as there are 150 caves within half an hour walking distance from the village.
It takes time for people to learn to utilize new technologies and to incorporate them into their work. One might expect this paper to have a different title, such as Digital cave photography. However things have changed in the past 5 years to such an extent that the topic deserves to be named properly. For quite some time in many web publications, especially American ones, the term photography now refers to digital photography, while the standard, film-based photography is termed as traditional photography. Consider for one moment the impact of the digital camera on the field of cave photography. The leap forward from film to digital images in cave photography is as big as the leap from typewriter to computer. It is always a pleasure to go up, and a great pain to go down (usually as a last resort when all else fails).
On the other hand digital photography, frankly speaking, is not exactly the honeymoon. The quality of digital images rivals good film photographs, but there is still a considerable way to go. There are a few magazines that still do not publish digital photograhs due to inadequate reproduction quality. And the magic of monochrome prints will never go away from those who have ever tasted it. Many of us also feel very uncomfortable in the role of riders on the consumer merry-go-round, long experienced in the field of computers. One awaits a new technological pet with great joy and excitement, pays for it dearly, falls in love with it and yet, after very few years, it either breaks down beyond repair or has to be sold off for pennies or thrown into garbage as it is obsolete and its use does not make sense any more. A car can last for ten years or more and traditional, film-based cameras used to provide even longer good service.
Russian Lubitel, twin-lens reflex camera, kept me company
from mid-sixties, when I started my cavegoing career at 17 (photography at
8 with a Polish 6 x 6 folding camera Druh) till the end of seventies of the
past century and has kept an honorary post on the shelf of the living room
till this day. It had a modest lens,
Tomaž Planina shamelessly compared it to "the bottom of a beer bottle",
and it was inexpensive, the cost was about 50 euros, but still
this camera was a very decent tool when in the right hands.
Figure 1: Widening the narrow passage in Skednena jama cave, Jozl, Tačka, Klok; Lubitel, f 11, 1/30 sec., negative film Ilford HP 4; illuminated by flashbulb Philips PF3; self-timer, 1970
In the cave, such closed aperture required a bit more flashpowder, and a two-metre flame coming from the incineration of 50 grams of powder made much softer shadows than any electronic flash will ever produce. There were drawbacks of course, repeating the shots was not a very practical option - the dense cloud of smoky fog, which lifted after the firing could easily turn finding exit from the hall into a mission impossible. On the other hand this pyrotechnics had a special charm of its own: the tense moment after the firing when the fire slowly crawled to the flashpowder, the burst of the blinding flame, the mushroom-shaped cloud, like that of an A-bomb, but was not without danger and risk. The skin on the wrist of the author's right arm is, after many years, still more fragile, sensitive and lighter in colour, a consequence of second-degree burns acquired after an accident during the preparation of half-a-kilo of flashpowder in the garden; the flame reached to the roof of a 2-story house.
After Lubitel, in 1976, a second camera followed, single-lens reflex Leica format (24 x 36 mm) Fujica ST 605. It was the first such camera offering both a fast silicon-based through-the-lens exposure meter at an accessible price (500 DEM, what would translate to 250 euros). Even today the camera has no real flaw, save that it is not digital. It never broke down. The only trouble worth mentioning happened after ten years of service. The shutter release got stuck in the middle of an important assignment: documenting the wedding of an acquaintance's daughter in Laze. It would not go down any more by any force. A moment of panic followed until the bride's father, well versed in agricultural technology, gave some prompt advice: a drop of tractor oil and the wedding could continue to the satisfaction of everyone involved. The following day, while examining the camera's documentation, I found that the instructions for use actually included a sentence stating that the camera shutter release has to be oiled every 10 years. In cave photography, flashpowder has been replaced by the much more convenient electronic flash but the real joy was still missing. If the scene was illuminated from the camera using the automatic setting on the big flash (Metz Mecablitz 45), surely the object in the frame would be clearly visible in the picture, provided of course that the distance was within limits of some 5 - 7 metres.
Figure 2: Polona, Marija, Matjaž and another Matjaž on the rock in the river Rak, above the cascade in Planinska jama cave, Fujica ST 605, f 5.6, 1/60 sec., ISO 100, Kodak negative daylight film; illuminated by 2 x Metz Mecablitz 45 - from the camera and from the right; 1993
Illumination from the side or even shooting against the light was
more of a problem. In the cave everything seemed perfect,
we all were very impressed and enthusiastic. However, the results, obtained
a couple of days later, were not quite as expected. There was hardly any
image taken in a cave that you could be 100 % sure it will be OK. Because of the better
tonal range, with details in the shadows as well as in the highlights,
because of better rendering of the skin tones, especially on portraits
but also because of much easier way to photographs on paper I used
colour negative film, not slides. All the colleagues were of course
shooting slide film; they were of more practical (some evil soul
would say "scottish") nature. Such films had prepaid processing, they
had to be sent by post to some authorized developing centre abroad, and it
took several weeks to get the slides back. The concept of digital photography
had not been thought up yet, and the best technology to dream of, at that time, was the
Minolta flashmeter (Flashmeter IV), used by NASA astronauts on the moon, which
costed an unreasonable sum of over 1.000 US dollars.
In short, good cave photography is also possible with traditional film-based technology, only the road is longer and more difficult. Two good shots per excursion can be considered a good outcome, three or more an outstanding achievement.
It is much older than one would think. The first digital camera, Mavica by Sony (acronym from MAgnetic VIdeo CAmera), built in 1981, was actually a TV camera which stored 490 x 570 pixel images (280.000 pixels, CCD sensor 10 x 12 mm) on two-inch floppy disks. It was already a SLR (single lens reflex) with three exchangeable lenses (25mm f/2, 50mm f/1.4 and a 16-65mm f/1.4 zoom) and a single shutter speed setting: 1/60 sec. It was powered by 3 AA cell batteries and the pictures could be watched on a TV screen. Mavica and the other digital cameras that followed were not intended for the consumer market, but for professional use. Development slowly decreased the size of cameras and augmented their capabilities and at the end of the nineties the first digital cameras for amateurs appeared on the market. They were more of a point-and-shoot class and the supporting infrastructure, laboratories that would print digital photographs on photo-quality paper, did not really exist outside United States.
The next milestone has been the introduction of the
950 camera by Nikon in the spring of 1999.
It was not a SLR, following the current
terminology it would be described as a compact camera, but it had the
resolution of 1,200 x 1,600 pixels (2 mil., sensor size 4.8 x 6.4 mm)
for excellent 4 x 5 inch prints and decent 8 x 10 inch
(A4) sized enlargements, zoom lens 7 - 21 mm, which translates into 38 - 115 mm at
the Leica format ("sensor" size 24 x 36 mm). Aperture (f 2.8 wide open)
and shutter speed could not be set manually; one had to live with the
automatic selection, which, in the darkness of a cave, opened the shutter for
the maximal 8 seconds. Two other prerequisites crucial to cave
photography, the manual distance setting and a connector for external flash
(Nikon only), were present. Manual distance could be selected from 10
values, the longer 3 being 3 m, 7 m and infinity. The designers of the
camera however, made a very unwise decision to turn the flash off at the manual distance
setting of infinity - they probably thought that it makes no sense to
shoot over 7 meters with the weak built-in flash. Despite all the described
flaws, the good points, including the price at an acceptable range around
1.000 US dollars (which translated into 2.000 in Slovenia at
the time), tipped the scales into camera's favour.
Besides the two main benefits of digital photography, an instantly visible, good approximation of the picture taken on camera's display with ca. 100.000 pixels (on Nikon CP 950 it has a 2-inch diagonal) and the possibility to immediately delete an unwanted shot from the memory medium, the technology has some other advantages. The media, postage stamp sized and up to 2 mm thick cards, is reusable several hundred times; the pictures are easily transferred to a computer and from there onto CD ROM (it holds from 250 to 500 photographs, 6 or 5 million pixels each); media cards are growing larger in capacity every year, with 3 or 4 such cards, at a total cost of less than half the camera's price - it is possible to cover the needs of a month long photo expedition. Another very pleasant bonus of digital photography is also a complete lack of garbage in the picture. In traditional photography, even with utmost care, there is always some small hair or fiber on the negative, a tiny particle of dust and scratches, introduced while making enlargements. It all shows on paper or in projected images and spoils the fun considerably.
So Nikon Coolpix 950 proved itself as a good camera. From July 1999 until November 2001 the author took over 4500 pictures, mostly in non-cave environments, but also in some cave experiments. A successful example is a boating shot from Najdena jama, also used for the title page of the Ljubljana speleo group's web site,
Figure 3: On the water barrier before Lijak in Najdena jama cave: Jozl, član Giovanni and Manč on the way back, veteran's excursion (it takes place the last Saturday in May, every year); Nikon CP 950, f 2.8, 1/60 sec., ISO 100, auto white balance; illuminated by Nikon SB 28 flash from front and Metz Mecablitz 45 from the left; May 2000
http://www.speleo.net (without text it can probably still be found at the URL http://fflj.ff.uni-lj.si/~jakopin/slike/slike/pj01516b.jpg). In November 2001, the destiny, which often helps put things in order, stepped in - the length of my both employments (full time, part time) has been switched and the camera had to be returned to a colleague for further, more academic use. The purchase of my own digital camera was inevitable.
At that time the true successor to CP 950, Nikon
5000, had been introduced. Geared towards a more professional use, the camera
had much better cave photography features.
The resolution was up to
1,920 x 2,560 pixels (5 mil. in all, sensor size 6,6 x 8,8 mm), which translates
into acceptable enlargements till approx. 60 x 80 cm (24 x 32 inches),
zoom lens 7 - 21 mm, i. e. an equivalent of 28 - 85 mm in Leica format.
No accessible digital camera at that time went so far on the wide angle
side, a point particularly important in cave photography; in a gallery it is
possible to go back only to the wall and no further, and for capturing the entire hall
in one frame such wide angle is a real blessing.
Instead of a dedicated Nikon flash outlet, the CP 5000 had a full hot-shoe
connector; a true necessity since it was difficult to use the built-in
flash whose effect was often unpredictable and inadequate even at
It was possible to manually set all the basic parameters: distance (from 2 cm to 10 m and infinity), aperture (again 2.8 fully open) and shutter speed - it improved from 8 seconds to B (bulb), maximally 5 minutes. Still missing was the very useful shutter speed setting T (time) from the old traditional cameras, i. e. to open the shutter by pressing the shutter release once and to close it after the exposure has been completed, with the second click on the shutter release button. As it is not possible to hold the finger on the shutter release button for 5 minutes without shaking the camera some solution had to be found. Since the remote control by Nikon is inconvenient and less suitable for cave environment, a friend from Laze, Jože, a specialist in wood and metal, curved a galvanized iron plate (240 x 8 x 0.6 mm), otherwise part of a window fitting. He drilled a hole at one end, where the camera tripod mount would be located and another one on the other end of the plate, curved to fit just above the shutter release button. Jože fitted this hole with a large metal knob and a screw. Turning the knob moved the screw downwards and it pressed the shutter release button (shutter speed set to B). Turning the knob in the other direction, after all the flashes have been fired as many times as necessary, released the button and closed the shutter. So it again became possible to take cave photographs in a very similar way as in past 100 or so years, the only difference being the distance setting. It was not possible to sharpen the lens looking through the viewfinder. The distance had to be estimated and the corresponding closest possible value selected in the control display.
Back then, the price of the camera depended very much on the place of purchase. On the other side of the Atlantic Ocean it was 1,100 dollars and 1,600 euros on the northern side of the Alps. The dilemma where to buy was resolved in favour of the world beer capital (not Milwaukee) after watching the film Lord of the rings.
Figure 4: A view from the entrance of the Cueva de Punto Blanco cave towards the bay Bahia de San Marcos, Klok; Nikon CP 5000, f 7.0, 1/630 sec., ISO 100, white balance set to fine; illuminated by available light and a full flash from Nikon SB 28, Tenerife, May 2002
And when you see him on the road, "young man" with white mustache (the hair, if any, is hidden below the cap) in the black cycle wear, so tight that every muscle stands out, with sunglasses in the colour of the rainbow, bowed above the handlebar of a bicycle that would do justice to the winner of "Tour de France", how he is happily pedaling towards his destiny, you cannot but think what one would normally think ... for instance the saying that ends with "... for theirs is the kingdom of heaven". Yet it is not difficult to come to a conclusion - so what, if I delve a little bit deeper into the cave photography, it will not be such a shame, caves are not so fashionable, at least not many will see me doing it. The alternative, to enjoy a good drink in front of TV, is indeed quite tempting and taken seriously by many, yet it somehow does not fit into the image of an ex-caver.
So it all seriously began at the end of January 2002
(the pictures can be seen on the web page
http://www.jakopin.net/primoz/slike/020203.html) - at first in
the Jama v Škofjem lomu cave near Laze, in a ponor-type cave
of the Planinsko polje where W. Putick made way through a side gallery which leads into the hill
using mine-type wooden supports in the 1880-s. It was a solo excursion,
with the backpack in the acting role in the picture, side flashes
on tripods, and with the following equipment: Nikon CP 5000, 3 tripods,
Nikon SB 28 flash, two Metz Mecablitz 45 flashes, two Metz Mecalux 11
optical slave flash control units and an additional shutter release for
the camera, used at the shutter speed B (made by Jože Jurca from Laze).
It turned out that this set performs quite well, and that it is advisable, for elimination of hot pixels, to have noise reduction turned on for long exposures. The camera sensor is composed of five million tiny light sensitive receptors (on Nikon CP 5000), each of which contributes one pixel to the image file. These dots are of course not all of the same quality - the vast majority behaves as expected at all times, even at speeds longer than 1/30 of a second - dark pixels in the dark parts of the picture, light pixels in the highlights and also of the correct colour, while around 20 of this army of receptors are bad players; at long exposure times they emit green or violet or white pixels even in the shadows or in total black of the picture. There is a setting in the menus of the CP 5000 which instructs the camera to correct those bad pixels after exposure, but it takes some extra time, as long as the exposure. If the shutter on a cave shot was open for 1 minute, the camera will make an extra exposure of the same length with the shutter closed. On this black image the bad pixels are located (those that are not black) and corrected on the original cave image, with the help of the pixels emitted by the neighbouring good receptors. The only flaw was that one had to wait for an extra minute before the picture could be verified on the camera display (noise reduction on digital single-lens-reflex cameras such as Canon 300 D is automatic and does not require extra time).
The white balance feature on camera was set to electronic flash, which seemed adequate, at least in the Jama v Škofjem lomu cave. A longer excursion in the famous Mačkovica cave, again near Laze (probably the last big cave with free access) followed, with participation of Andreja Jurca from Jakovica; the pictures are on the same web page as the previous excursion. For the picture below
Figure 5: Passage above Dvorana z Mojzesom hall in Mačkovica cave, a view in, Matjaž, Nikon CP 5000, f 4.0, 3 seconds, ISO 100, pre-set white balance; illuminated by two carbide lamps, of Matjaž and of the author, February 2002
the white balance had been determined before the exposure using a white sheet of
paper, illuminated by a carbide lamp; the available setting for electrical room
bulb (incandescent) which seemed close enough, did not yield a usable
result. The black & white version of the picture, printed here, looks
quite acceptable, but in the web version of the paper,
http://www.jakopin.net/primoz/clanki/nj_2004_1 it is evident that
it has a strong yellow-green cast. It is quite difficult to select a
proper white balance in the cave - the other photographs from Mačkovica
show that the white balance, set to electronic flash on Nikon
CP 5000, also failed on light-coloured dripstone surfaces: the colours
are too warm, the entire scene appears red. The setting to fine (sunny weather)
proved better, with more realistic colours.
Depth of field at the wide-angle side of the zoom (7 mm), used on the majority of the pictures, proved quite satisfactory in most instances, even at the aperture wide open (f 2.8, the usual setting). This combination is also the most economical for cave photography: the scene is close to the camera and the flashes give the most illumination - the amount of light decreases with the square of the distance. In the summer of 2002 and in the early autumn more excursions to Mačkovica were made, most with participating members of the Lanski vrh Tourist club from Laze: Polona and Simona Šušteršič, Brane Simšič, Uroš Stepišnik from Ljubljana and Tomaž Pehant from Maribor. A number of photographs were taken, which were displayed in 2004, on exhibitions in Zaghouan, Tunisia, in Ljubljana and in Laze ( http://www.jakopin.net/primoz/razstave/2004/laze).
At the end of May 2002 there was an opportunity to visit
the volcanic caves of Tenerife, Canary Islands. The camera was put to
good use there, too; the pictures can be seen on the web page
http://www.jakopin.net/primoz/slike/tf2002.html and one, in Figure 4,
is included in this paper. It was an interesting experience because of
high cave temperature, around 20 deg. C; light mountain shoes, a
cotton over-suit and cotton gloves were all the clothing needed. Gloves
were needed because of small sharp stalactites which formed as
the lava, dripping from the ceiling, solidified. The dark grey walls of lava
were difficult to illuminate with electronic flashes. A similar problem
exists with Mangane-oxyde covered rocks in the riverbed of Planinska
jama, but in lava caves the space was somewhat easier to work in
because of the smaller distances, 5 - 10 metres.
In September 2002 the technique of taking pictures in pair, with flashes on two tripods, has been successfully tested during the short visit to Vjetrenica cave (Figure 12). The 8 km long cave is situated on the southern rim of Popovo polje in Herzegovina and was the second most famous cave (after Postojnska jama cave) in the former Yugoslavia; it was electrified, with wide paved pathway along the first 1.5 km of the main channel. The cave got its name (could be translated as Wind cave) from the strong winds, noticeable at the low water level, in the narrow passages close to the entrance and, especially, in the entrance itself. In no other cave is there such drought as in summer on the plateau before the Vjetrenica. During the latest war in the mid-nineties, electrical installations were seriously damaged and the cave closed. An opportunity to visit such a glorious cave on your own, even for one day, was an exquisite luxury. Even at middle distances, up to about 10 metres, in a gallery 12 x 5 metres, 3 flashes (1 x Nikon SB 28 on camera, 2 x Metz Mecablitz 45 with servo controls on tripods) gave satisfactory illumination. Only for the photograph of a larger hall (Figure 6) were more flashes required - 3 in front and around 5 from behind the wall at left; it was not feasible with a team of only two, one of which had to pose in the picture.
Figure 6: Side collapse at the Tie, junction to Radovanović gallery in Vjetrenica cave, a view out, Aleksandra; Nikon CP 5000, f 2.8, 1/15 sec., ISO 100, white balance set to "fine"; illuminated by Metz Mecablitz 45 on camera, Mecablitz 45 and Nikon SB 28 from the side, September 2002
The cave is otherwise relatively bright, such as Mačkovica,
has a short, but very picturesque water gallery and very
large, several hundred metres long, ascent in the Cvijićeva dvorana
hall. During the visit the water level was high, the siphon already at
1 kilometer from the entrance, there was no wind.
In January 2003 the first excursion to Križna jama cave took place, into Pisani rov (Gay-coloured tunnel), with only one boat. The original idea, to go first to the end of the gallery and to take pictures on return, had faltered - sightseeing and photography in side parts (Figure 24) consumed nearly all the precious working time, limited to around 2 hours at that distance from the entrance, and the best scenes had to be left alone. The experience was nevertheless very important; it became clear that for posing in the picture a small, custom-made boat will be necessary and that at least two boats are required for other members of the team.
At the end of January and in the first half of February 2003 a small expedition to the caves of the Rurutu island followed; pictures can be seen on the web page http://www.jakopin.net/primoz/slike/rurutu_2003). Fulfillment of my almost thirty year old dreams was made possible by a convergence of favourable circumstances, mainly connected to the author's late father; irony of fate had it that the father otherwise strongly opposed son's caving activities. Rurutu is part of the Austral islands archipelago in French Polynesia, and like all islands in the group it is of volcanic origin. A volcano rises from the bottom of the ocean, ceases with activity and starts to descend back, forming a calcite coral reef around its shores. When the tip of an extinct volcano slips below sea level, only a circular or oval coral reef with a lagoon in the middle, an atoll, remains. On Rurutu the tectonic movements were not as simple as elsewhere, not only once up and once down, but the story got repeated several times. Calcite coral reef, tens of meters thick, was lifted into the air several times, up to 100 metres above sea level. Without constant exposure to sea water the reef stopped growing and the rainwater started karst processes, which lead to the development of caves, homes of the first island natives who fled Tahiti 900 years ago. After a heavy defeat, caused by a sudden attack of the mountain tribe, the surviving members of the coastal group embarked in three pirogues and under the cover of the night set off in the direction of Moorea, a neighbouring island of Tahiti. In the darkness and haze they missed it and after 3 weeks of ocean travel landed on Rurutu, on a beach with a cave where they found good shelter.
Figure 7: Cliff south of the Teuta cape with cave remnants and with the entrance to Ana Eva cave left above the beach, Nadja; Nikon CP 5000, f 5.6, 1/300 sec., ISO 100, white balance set to "fine"; Rurutu, February 2003
Because they mourned the dead relatives they gave the cave the name Ana Eva;
it could be translated from Tahitian language as the Cave of Grief (Ana = Cave).
There are about 30 caves on the island, and during 17-day long stay
half of them could be visited. The biggest one is called Ana A'eo (Figure
17), and its hall is nearly as big as the entrance hall of Vranja jama
cave near Laze (around 40 x 20 x 15 m). Temperatures are even higher
than in the volcanic caves of Tenerife. A cotton oversuit is too warm.
All that is needed is a straw hat, thin shirt, shorts, garden gloves and beach
sandals with good straps for support and a sole that can resist not
only salt water but also very corroded, sharp rock surfaces.
At the end of May 2003 a very good veteran's excursion to Najdena jama cave followed. A team of three, with Tomaž and Marjan, managed to take about 10 very satisfactory pictures, using three Metz Mecablitz 45 flashes and two weaker ones, with a guide number of 30 (metres). The cave is mostly dark, and wet clay is as difficult to overexpose, as are the black riverbed walls in Planinska jama cave, but using multiple flash firings on the same picture somehow works, provided there is enough time available; every shot takes several minutes, which, with some corrections, quickly turns into a half-hour per picture.
In the August 2003 it was Vjetrenica for two once again, this time with a strong wind and for three full days. About 50 usable photographs were taken, some of them with flashes mounted on tripods in the water.
Figure 8: Natural bridge between the eastern and western lake of Modra špilja cave, three girls from Komiža; Nikon CP 5000, f 2.8, 1 second, ISO 100, white balance set to "fine"; camera on tripod, the scene illuminated by available light coming from below the surface of the eastern lake, Metz Mecablitz 45 at full power; island of Biševo, August 2003
An interesting experience was shooting in the Modra špilja cave on the Dalmatian island of Biševo, southwest of the island Vis. The cave is a cavern in the rock, with a diameter of about 20 metres. It has two connections to the sea. There is a narrow land passage, barely wide enough for a person to squeeze through, and a large passage some 3 metres below sea level. Light enters from the large passage and is the brightest at around 11 a. m., when the amount of light above the surface of the eastern lake is approximately f 2.8, 1/30 sec. at ISO 100. The blue water-filtered daylight gives all the objects in the cave a special, silvery look. Unfortunately, serious photography is not possible at that time because of intense tourist traffic. There is an artificial entrance on the western side of the rock where an endless row of small tourist operator boats (10 seaters) pours in and out from 9 a. m. till after 3 p. m., also the time when there is an admission fee. Later in the afternoon it is better, but the light intensity falls by 5 f-stops, to f 2.8, 1 sec. at ISO 100. Yet, a different set of problems is waiting for the photographer at the other large cave on the island, Medvidina špilja, named after a Mediterranean monk seal (Monachus monachus, medvidica in Dalmatian dialect of Croatian) that once lived there. At the end of the water channel, some 100 metres from the entrance, in total darkness, it is getting quite narrow, around 1 metre - wider below the water surface but more and more narrow above. Long waves, which seem to everybody like calm sea in the open, start making real trouble in the cave - the water level moves up and down by around 40 cm (1 foot and 4 inches). Rubber boat is lifted by the water, gets stuck by the walls, the wave flushes over it and the photographer with his gear finds himself immersed in the water to the waist in a split-second.
The optical viewfinder in Nikon Coolpix 5000 did not show the whole
picture. Above the upper edge of the picture shown, some 10% of the
height was added to the picture, but it was expected, and while shooting
landscapes, that you just took very little, almost no sky above the
hills, knowing that in the picture it will be just fine. And as I
just got used to the camera well, Nikon Coolpix 5000 was
close enough to what a cave photographer could wish for himself, the fate steps in again.
The successor to CP 5000,
Nikon CP 5400,
actually came about a year later, but it was burdened with some rotten
rationalizations and compromises: the display was diminished, instead
of 1.8 inch diagonal at CP 5000 (it was 2.0 inch on CP 950!) there was
only 1.5 inch, which translates into an area, smaller by one third,
zoom has been prolonged from 3 x to 4 x in the same lens housing,
which forced an introduction of a smaller sensor, less light for every
pixel and slightly less sharp pictures. The maker even decided to cancel
the small control display with basic settings, such as aperture, speed etc.
It was immediately clear that the CP 5000 to CP
5400 transition was the usual trick of modern producers, who do not
want to lower the price of a well established product but prefer to
discontinue it and to offer a new product, on paper slightly better, but
actually slightly worse, for the same price. It is obviously much better
to stay with the product one already has.
But unfortunately it was not possible in this case. On
Friday, night before the excursion in Najdena jama, in mid-September
2003, the camera was in perfect working order. On Saturday morning, it
was not. As it happens sometimes in winter, you wake up in the morning,
look through the window and, instead of dull, grey landscape, you see a
wonderful white, field covered with new snow; only this time it was the camera
display that went all white. When turned on, it did not show the last picture
taken, but an image with all pixels white. No matter what the settings
were or what buttons were pressed, the outcome was always the same. It
was still possible to take pictures, like on a traditional camera, but the
outcome could be checked only later, after transferring the picture to
a computer. The settings, normally selectable through the menu on the display,
could be changed only if the camera was connected to a TV set or if the
key sequence was remembered from before - i.e. press the Menu button,
press arrow right, arrow down, arrow right again, twice arrow down,
followed by Enter key and the white balance was changed from fine
to fluorescent. The whole thing could be described as sort of
digital traditional photography. The excursion to Najdena jama
was nevertheless a success and so was one very good picture; others,
including some quite breathtaking, are on the web page
The camera has been sent from Nikon outlet in Ljubljana to the
regional service center in Germany and after 14 days it was clear that
the repair would cost 90 % of the price of a new camera. Caving buddy
Matej was looking for a 5 mil. pixel camera at a very affordable price,
for quite some time and now he has found it, for some 220 euros.
What to do next? Nikon CP 5400 was not a good choice. What about Nikon CP 5700? - the latest and greatest from the labs of this maker: 8 x zoom, great for taking bird pictures, but digital viewfinder (slow, totally dark in the cave), wide angle side of the zoom too weak, only 35 mm in Leica equivalent. Some other choice had to be made. In September 2003 the first truly affordable digital single-lens-reflex camera, Canon EOS 300 D, was launched on the other side of the ocean with much hype. For the first time an average consumer was able to look through the lens and actually see what he gets, WYSIWYG or what you see is what you get. If the price of the latest traditional (film) camera in this category, the Canon EOS 300 SLR V (Rebel TI in the US) with lens (28 - 90 mm) was at about 300 US $, the price of the digital 300 D (Digital Rebel), with D for digital, were at 1,000 US $. It was much more but, for the first time, below the psychological barrier and, also, a reduction of predecessor's (Canon 10 D) price by almost one half. Other data were no less promising - 6 mil. pixel sensor, 2,048 x 3,072 and 15.1 x 22.7 mm, 3 x zoom, 18 - 55 mm (Leica equivalent 28 - 85 mm), aperture f 3.5/4.5, speeds to 30 seconds and B (up to 2 hours, as much as the camera battery would last), sensitivity ISO 100 - 1600. Another bonus for many was interchangeable lenses, the entire Canon EF series (over 50 pieces) and a long list from independent lens makers such as Sigma or Tamron. The sensor size was smaller than 24 x 36 for Leica format and therefore there was a focal length multiplication factor of 1.6 - 50 mm lens, for instance, gives on 300 D an image, which would be obtained by an 80 mm lens on a traditional SLR (50 times 1.6) mm. And there are other things to think about - the name Canon does not have such real flair for many, it gives association to guns, probably sounds nicer to artillery fans, while Nikon (pronounced in a European way, Neecon) sounds almost like Nippon, razor sharp, clean cut, for many years a symbol of technical perfection. First name is the first, but if they do not have a right product when you need it, one has to look elsewhere. Be it this way or another, in October 2003 Canon 300 D was available in small quantities and with some effort the author had obtained one. It cost him around 40 % more than the US price, but still less than Nikon CP 5000 19 months ago.
Figure 9: Freetime around bonfire in the evening after the excursion: Matej, Stepo, Boni, Matija, Bina and Bojana; Canon EOS 300 D, f 5.6, 4/10 sec., ISO 200, white balance set to "sunny"; the scene illuminated by available light and built-in flash; Lupertova jama cave, October 2003
Several very satisfying excursions ensued during the remaining part of the year, two to Križna jama cave, one to Šimnovo brezno pothole above Bled and another one to Ocizeljska jama ponor cave near Divača, where pictures 24 and 25 were taken. At the end of January 2004 the camera did well at the expedition into the caves of Tunisia, with 300 pictures (dust clogged the lens mechanisms on the second occasion in June); it fulfilled the expectations. The camera is indeed twice as bulky and heavy as the CP 5000, if kept under the over-suit, especially with an external flash mounted, it makes one feel, while bending or in narrower parts of a cave, like Quasimodo with his hump in front and not in the back. Another disadvantage is the picture height : width ratio, it is 2 : 3, worse than 3 : 4. Most other parameters are better. Surprisingly the new camera is a good match to Nikon SB 28 flash, which occasionally caused problems on the CP 5000. Coolpix sometimes, even with SB 28 set to manual (M) and with internal flash turned off (via menu), used to fire some weak preflash, for the reduction of red eyes or for checking the white balance, which triggered optical servo controls on external flashes. So all the extra flash units fired, but prematurely and in the picture only the effect of the SB 28 could be observed. Combination of 300 D and SB 28 does not try to impress with some quasi artificial intelligence and all the flashes get fired as required.
The number of photographs which can be saved on a single
memory module, on a tiny CF (Compact Flash) card, depend not only on
the capacity of the medium but also on the selected resolution and
compression level for the image files. If the camera sensor has, say,
6 mil. pixels, the picture can have at most 2,000 x 3,000 coloured
points. All digital cameras certainly can save the picture with
smaller pixel number. For instance, Canon EOS 300 D can save the
picture, captured with 2,048 x 3,072 pixels (6.3 mil. in all), in full
resolution (large) or as 1,360 x 2,028 pixels (2.8 mil., medium) or even as 1,024 x 1,536
(1.6 mil., small). A picture can be saved without the loss of any pixel or using a
lossy compression algorithm with different levels of compression.
Speed of saving and of playback, saving quality and picture file size
all depend on these selections. EOS 300 D gives 7 different
possibilities with saving of the image in raw mode, all pixels as captured by the sensor,
2,048 x 3,072 pixels, being the richest in information content.
The file is about 7 MB long and the white balance does not need to be
selected at the time of shooting. The decision will be made later,
during the postprocessing of the picture in the user's computer.
Besides raw mode of saving there are six further possibilities
to save the picture using the JPEG (Joint Picture Expert Group)
compression standard, which is based on discrete cosine transform and
was adopted as international standard in 1992 (the files usually have
the .JPG suffix). There are three
abovementioned image sizes (large, medium, small), each of which can be
either moderately (fine) or strongly (normal) compressed. The sizes of
saved files are about 3.1 (fine) and 1.8 MB (normal) for the large size (6.3 mil. pixels),
1.8 and 1.2 MB for medium (2.8 mil. pixels) as well as
1.4 and 0.9 MB for the smallest size (1.5 mil. pixels).
What to select? Starting with the assumption that only serious pictures will be taken, it is always a bad decision to damage any of them by using a poor saving setting. So the choice actually narrows down to raw mode (recommended by gurus and purists of digital photography) or to the best JPEG mode (large, fine). Raw mode has the drawback that the saving takes much more time, and the time to get the picture on display for checking is also over 10 seconds instead of about 1 to 2 seconds for pictures saved in JPEG mode. Raw image files also have to be postprocessed in the computer for any further use, which again takes time. So it is reasonable to use the best JPEG mode, unless the picture is extremely critical or the illumination is such that the white balance cannot be well estimated. For Internet applications the pictures, of course, are diminished in size and strongly compressed, while the originals stay in the archive, big and best for any later use.
In traditional photography, the decision of how the medium
will respond to different light sources is made beforehand,
by the film selection. Black and white films, for instance,
are orthochromatic, insensitive to red light of low intensity as used
in the darkroom; panchromatic, sensitive to all colours; infrared
films, sensitive not only to usual light but also to heat, the
invisible part of the red spectrum region.
The term colour temperature is connected to the temperature of the light source. As with standard temperature, it is measured in degrees Kelvin (K). A source does not emit any light at 0 deg. K, which is the same as - 273 deg. Celsius, but starts emitting light rays as it gets warmer, at first in the infrared region of the spectrum, as the radiators of the water central heating, later also in the visible part of the red spectrum region, such as coals or slowly burning fire, at higher temperature the colour moves into the yellow region of the spectrum, such as the bulb filament, and at last, at very high temperatures, the colour is becoming increasingly blue. So the match flame has a colour temperature of 1,700 deg. K, candle flame 2,000 deg. K, electric bulbs from 2,600 (60 W bulb) to 3,200 deg. K (halogen bulbs), neon bulb 3,400 deg. K, daylight an hour before sunset or soon after sunrise 3,800 deg. K, ordinary daylight 5,500 deg. K (sunlight at midday, in the summer and with the sky, slightly covered by white clouds), the colour temperature of electronic flashes is from 5,500 to 5,800 deg. K, clear blue sky 12,000 deg. K and clear blue sky high in the mountains 20,000 deg. K.
Colour films, we all once used for cave photography, can be divided into two basic groups: daylight films (5,500 deg. K), for scenes illuminated by electronic flash or for scenes in cave entrances and tungsten films (3,500 deg. K), suitable for pictures, illuminated by carbide lamps, electric bulbs or flashpowder. If the picture of a cave entrance was by accident taken on a tungsten film, the image would be intensively blue while the scene, illuminated by electric bulbs, would be shining in all the nuances of yellow and red on a daylight film. Light sources with different colour temperature than daylight or tungsten require the use of special filters, mounted in front of the lens.
Digital cameras are much more advanced in this field, white balance can be selected for every picture and there is a choice between various settings. Outdoors it is usually safe to choose an automatic white balance setting, where the camera computer makes the decision. It works for sources between 3,000 and 7,000 deg. K and it is reliable provided the picture is at least a little bit colourful, of mixed colours, preferably including white. Very monochrome motifs, probably also without white colour, require user intervention to obtain acceptable results. Besides automatic there are usually the following other settings: daylight (symbol of the sun), light in the shadow, overcast sky, electronic flash, electric bulb light (incandescent), neon bulb light (fluorescent) and the custom white balance setting. The latter requires a sheet of white (paper), the user illuminates it with a light source, carbide lamp for instance, and saves the measured value by pressing the shutter release button. It can be used for subsequent shots. The second solution is to save the picture in raw mode, the pixels as received by the camera sensor, and to apply the appropriate white balance later, during postprocessing. The flaw here is just the fact that the colour temperature of the carbide lamp flame is rather low, below 2,000 deg. K and, therefore, falls out of range - on Canon EOS 300 D only values between 2,800 and 10,000 deg. K can be selected. So the picture, illuminated by carbide lamp, saved as raw and later converted to JPEG file in the computer at 2,800 deg. K, still has a very noticeable yellow hue (see Fig. 5). Similar can be said for illumination with electric bulbs - their colour temperature changes (lowers) with the distance - it is much higher at close distance than it is at 15 or more metres; again the pictures are more yellow or even red than would be desired. The problem can of course be turned to the bright side - warm light of carbide lamps and flashpowder gives the picture a vintage look and a special note or, one could say, a romantic flair.
Bottom line: if you happen to find yourself in a cave with a new digital camera, make some trial shots of the same scene and with the same illumination, electronic flash, for instance, and with different white balance settings. Examine the pictures closely and select the best white balance setting. If the setting to electronic flash gives too warm picture, choose white balance value for daylight. For illumination with carbide lamp measure the light with a sheet of paper or select the setting for artificial light (incandescent or tungsten). The same goes for illumination with flashpowder or with electric bulbs.
Caves are among the rare natural ambiences inside which the light source must mainly be provided by the photographer. This fact is however not only an additional problem but is, in the time of digital photography, becoming more and more of an asset. The photographer selects not only the viewpoint and the direction of shooting, which more or less determine the picture, but also makes such arrangement and positioning of light sources, usually electronic flashes, which will draw the objects on the scene in the most suitable, usually the most beautiful way.
When taking photographs in caves entrances' or in the vicinity it is usually best to use only the available light. The views of cave entrances from the outside, where the emphasis is on the environment, on rocky walls, vegetation, maybe the riverbed and where the entrance itself is more or less just a dark patch in the middle of the picture, are not so rewarding as the views from the entrance looking outwards. Such views are much more interesting because they have bigger contrast, show play of light and shadows, and emphasize the difference between the darkness of the entrance frame and the greenery, brightness of the outside landscape in a very attractive manner.
Figure 10: A view out through the Big entrance of Tkalca jama cave, Klok; Nikon CP 5000, f 2.8, 1/60 sec., ISO 100, white balance set to "sunny"; Rakov Škocjan, June 2003
The best time for taking cave entrance pictures in Slovenia is in
mid-spring, usually around first of May, when the trees just turn
green and the leaves are of vibrant light green colour. In just a
few weeks the leaves turn dark green and it takes very strong, direct
sun's rays to get a light picture. In such ample light the
photograph can be taken from the hand, otherwise a tripod is
obligatory. With longer exposure times, up to one minute or more,
acceptable pictures of views towards the entrance can be made from the
gallery deeper in the cave, from around the corner. Very popular are
for instance View from the bridge downstream towards the entrance of
Planinska jama cave or View to the path in Mahorčičeva jama of the
Škocjanske jame system.
If the walls in the entrance are dark and the entrance is not too big it is common practice to soften the black picture frame. Naked eye can see much more detail in the shadows than can be rendered by the camera's sensor. Care must be taken, of course, that the flash strobe is not too strong; it can eliminate the shadow completely.
The vast majority of cave photographers nowadays use
electronic flashes as a light source. Their power is given by a
guide number (GN) which is a product of aperture and distance at ISO
100, for proper illumination of the motive in normal conditions and for
distance in metric units. For users of English units (distance in feet
instead of metres) the guide number has to be multiplied by 3.281; in
this paper metric distances (and guide numbers) will be used.
If the flash, for instance, has a guide number 45 (such as Metz
Mecablitz 45) the motive 10 metres from the camera will properly be
illuminated at the aperture f 4.5, and at aperture f 8.0 for the
distance of 5.5 metres; because the quantity of light received is
falling with the square of the distance from the
light source, an aperture value will yield pictures twice as dark as
the picture taken with the preceding value. Values are given as: f 1.0,
f 1.4, f 2, f 2.8, f 4, f 5.6, f 8, f 11, f 16, f 22, f 32, f 44 and f
64. At f 64 the quantity of light
the camera sensor receives is 1/4,096 (0.000244) of what would be
received at f 1.0 (given the exposure time remained constant). The
flash guide number is given by the manufacturer and is, similarly as
the gas mileage, valid for ideal conditions. In this case it
would mean taking pictures indoors, in a room with light, possibly
white walls, where the motive is not illuminated only directly by
the strobe but also by the light, reflected from the walls and the
ceiling. When taking pictures in the open it is already necessary to
open the aperture by one stop more than indicated by the guide number -
for GN 45 at 5.5 metres one should use f 5.6 instead of f 8.0 - while
in the cave, where the walls typically are not very light, of
white dripstone, but are muddy or even darker, as in water caves,
it is necessary to open the aperture by 2 or even 3 values. In a
normal cave the aperture, for GN 45 and at the distance of 5.5 metres,
should be f 4.0, and even f 2.8 if taking picture of stones in the
riverbed of Planinska jama cave. More open aperture values
bring depth-of-field problems (if the distance is set to 6 metres,
objects 3 m away will not be rendered sharp) and lens quality problems.
The lens performance is at its best for the lower middle aperture values,
from f 5.6 to f 8.0 and is the worst at the aperture wide open, i. e. f 3.5
for Canon EOS 300 D kit zoom lens.
Virtually all the electronic flashes are also equipped with a sensor which measures the light, reflected from the motive. In automatic mode they will shorten the strobe duration in the moment when the motive is illuminated enough (for given aperture and ISO values). This mode is useful at very short distances. After more than several metres the full flash power is rarely too much.
An additional illumination problem in caves is connected to the person in the picture. Her or his face, if of Caucasian skin tone, is nearly always lighter than cave walls and her or his cave clothing and so tends to get overexposed, one could also say "burnt" or "washed-out".
Digital cameras, compact and single-lens-reflex, come with a small flash built-in. This flash is of course not big and has a small guide number, usually around 12. But it can still furnish quite well illuminated pictures at small distances, up to 2 or 3 metres.
Figure 11: The Count Monte Cristo squeeze in the Jama na meji cave, 10 m before the end - Andrej is coming out, photographer's legs in the foreground; Canon EOS 300 D, f 8, 1/4 sec., ISO 100, white balance set to "sunny"; illuminated by built-in flash; February 2004
Better digital cameras come with a hot-shoe on top, a mount
with contacts for an additional, more powerful flash, the start of
true cave photography. For considerably less than 100 euros
it is possible to buy a 4 mignon-cell (AA) powered flash, less than half a
kilo in weight and with a guide number around 30. Mount it on the
camera (if the camera will fit behind the caver's over-suit, it will
also fit with the flash mounted), switch it to "M" (manual) and you
are a new cave photographer. Though the flash is not exactly a
Mecablitz 45 (which is bulkier and heavier than most digital cameras),
the pictures up to 4 or 5 metres will suddenly become acceptable,
Many pictures taken "on the road", especially if some action like jumping, climbing or boating is involved, can be successfully covered with such "camera and external flash" combination. When an interesting scene pops up, which will vanish in a few seconds, there is no other way but zipper down, camera out, shutter release halfway down to wake the camera from sleep mode, quick check of the settings, point and click! ... as the friend Jože from Laze would use to say: Kr je dalu, je dalu (what was done, was done). Over one third of the images in this paper have been made with a camera and an additional flash on the hot shoe.
More horsepower is better than one pony alone, and the sensors of digital cameras, just like the film, love scenes which bathe in the light. If guide number 30 is not bad, GN 45 is better and 90 is quite attractive. And how does one get such firepower? Just use more flashes instead of one. Their guide numbers do not simply add to get the cumulative guide number, because of the fact, already mentioned, that the intensity of light is falling with the square of the distance from the source, but a formula exists, similar to the one for determining the distance between two given points in multidimensional space using Pythagoras theorem: cumulative guide number = square root of the sum of squares of guide numbers of individual flashes involved. If, for instance, there are two flashes with guide number 45 and one flash with GN 28, the cumulative guide number would be: square root (45**2 + 45**2 + 28**2) = square root (4834) = 70 (double asterisk is used as the operator for exponentiation and slash (/) for division). Or to turn the problem around: suppose the motive is 20 metres away and the aperture must be f 8.0, that is, the guide number should be 160. How many strobes with guide number 45 are necessary to get proper illumination? Number of strobes = square of the cumulative guide number, divided by the square of single strobe guide number. In the latter case it would be 160**2 / 45**2 = 25600 / 2025 = 12.6 or 13 strobes. Since it would be very difficult (and expensive) to use 13 flash units, the camera should be tripod mounted for long exposure (B) and less flashes used with multiple strobes. With only one flash at hand it would be necessary to walk around the space left and right behind the camera and fire the flash manually 13 times, for 13 strobes. The flash reloads its capacitor in 10-15 seconds and so the whole procedure would take about 3 minutes. The person in the picture should be placed in front of some large rock or stalagmite at the edge of the picture, with his headlight turned off, illuminated there with one strobe and direct further 12 strobes so that the person will be in their shadow. Two flashes would accomplish the same task in one minute and three flashes (hopefully with two assistants to hold and fire them) in a little over half a minute. And what about only one flash with a small guide number, say 20? The number of required strobes would be 160**2 / 20**2 = 25600 / 400 = 64. The flashing would take good 15 minutes and it would probably also be necessary to change the batteries in between. If the cave is darker, open the aperture more (which is a feasible solution with compact digital cameras, where depth of field is not such a problem) or set the speed from 100 to 200 or 400, which is feasible on digital SLRs with larger sensors.
Figure 12: Dripstone pans in front of Zlatna dvorana hall in Vjetrenica cave, Aleksandra, Nikon CP 5000, f 2.8, 1/8 sec., ISO 100, white balance set to "fine"; illuminated by 2 flashes Metz Mecablitz 45, 1 flash Nikon SB 28, 1 Voctron 3220 and 1 flash Demitron DC 32; September 2002
The previous picture was made with five strobes. In the middle of the
background there were two tripods with two Mecablitz 45 flashes and
one flash Voctron (GN 32), all together fired by two Metz Mecalux 11
servo control units. To the right side, out of the picture, a flash
Demitron (GN 20) was resting on a flat stone, turned towards the three
already mentioned flashes and its servo release Rowi against the
camera. The fifth flash, a Nikon SB 28, was mounted on camera, turned
out of the picture, towards the Demitron auxiliary flash. During the
actual shot the camera triggered the SB 28, which triggered the
Demitron and Demitron's strobe fired both Metz and Voctron flashes.
This arrangement ensured that the motive did not receive frontal
illumination (only in the lower right part of the picture), which
would spoil the contrejour effect of the main strobes.
Contrejour shots are very effective, water drops and wet surfaces shine out in the full beauty, but, as demonstrated in Figure 12, it already takes all available artillery at the distance of around 5 metres. Larger cave spaces require several strobes from every flash even for standard illumination, without contrejour, and it is necessary to use them to best advantage, as close to parts of the motive as possible. This is accomplished by flashing from behind various obstacles in the middle of the scene, such as piles of rock or speleothemes, strobes are not in the picture but they properly illuminate parts of the motive in front of them.
In times when the electronic flashes were big, clumsy,
expensive and required heavy external batteries, flashbulbs were
commonplace. Production of such flashguns started in 1930 and they were widely used by
reporters, today it is still possible to see them in the movies
made from the 1930's to the 1960's. Flashbulb units are small and
light, driven by little 9V battery. Their guide numbers are very
reasonable even for today's standards. A flashbulb is a small glass bulb,
filled with oxygen-enriched air and long, twisted magnesium,
aluminum or zirconium wire. During the firing the wire gets inflamed
and burns out in a short period of time (from 4 milliseconds to 2
seconds, depending on the bulb type), emitting a large quantity of light;
the picture in Figure 1 was illuminated in this way. Therefore the
bulbs are single use and have to be discarded after the shot. They are
of two kinds - of colourless glass, for tungsten white balance, and of
blue glass, for daylight white balance.
Compared to electronic flashes, flashbulbs have some advantages: longer discharge (usually around 1/30 of a second) generates a softer light, especially suitable for pictures of flowing water, such as rapids or cascades of an underground river. The strobe of electronic flash lasts only 1/500 sec. and every drop of flowing water is frozen in the air, which is very far from proper visualization of smoothly flowing water. Another advantage is the small size and weight (Metz Mecablitz 45 weighs with battery almost one kilo) combined with great power. A typical daylight-balanced flashbulb, such as Sylvania AG3B (B for blue), has a guide number of 70. Guide numbers of the biggest flashbulbs reach the value 200, more than 20 Mecablitz 45 strobes, and are therefore the only choice for action shots in large spaces.
And the disadvantages of flashbulbs? Most producers are long gone and only the remaining old stocks are on the market, available through specialized suppliers such as Cress Photo (http://www.flashbulbs.com). One flashbulb with guide number of 70 will cost around 1 US dollar. The only remaining producer of flashbulbs is the Irish company Meggaflash Technologies (http://www.meggaflash.com); they took over the last factory of the last traditional producer Sylvania, which ceased operations in the 1980's. Meggaflash bulb PF 330 has a guide number 200 and burns in two seconds. They cost 10 dollars apiece and are packed 48 per box, and one box is the minimum quantity for delivery. Another, minor disadvantage is high temperature at firing - it is easy to burn one's fingers, though bulb explosions are very rare.
It is a very attractive way of illuminating the scene. The camera is tripod mounted, the lens open for at least half a minute, and the motive is painted by traces of light, coming from electric headlight with, say 50 W of power. The headlight is crucial; it must have a wide enough angle of uniform light. 12 V halogen bulbs for illumination of store display windows come built in a small glass reflector, usually 20 W to 50 W, and have an angle of 35 degrees, which is suitable enough. The local plumber or tinsmith will make a metal casing for the headlight with a grip and a switch. 50 W is quite a lot of heat, and a sealed lead acid gel battery is suitable as a power source. Wrap it into a piece of blanket for protection and put it into a small backpack of heavy duty canvas. The battery and the charger can be obtained from a specialized battery store, a 12 Ah (amper hours) model measures 9.5 x 9.5 x 15 cm, weighs a little less than 5 kg and can sustain 50 W drain theoretically for 3/4 of an hour. In a cave, the battery lasts at least half an hour and such lamp kit has proved quite suitable for painting with light.
Figure 13: View from the bank at Sotočje (Confluence) over the river Rak, Planinska jama cave, Nikon CP 5000, f 2.8, 162 sec., ISO 100, tungsten white balance; illuminated by one 12 V / 50 W halogen bulb; July 2002
The author's first experiments were made with used car headlights, which
are inexpensive and can be obtained from a car salvage yard, and with
100 W auxiliary headlight with 12 V contact for the car's cigarette lighter,
but it did not work out well. These types of headlights have a very
pointed beam and it is impossible to illuminate the motive evenly.
Painting with light really requires a lot of patience and fingertips feeling (German word Fingerspitzengefühl is even better). It often happens that parts of the motive which are of lighter tones or which the photographer finds very attractive receive too much (and too long) attention. Very effective pictures can also be made by walking with the open headlight on the scene, preferably on a path and never turned towards the camera.
Flashpowder (Blitzpulver in German) was the traditional means of illumination in cave photography, from the second half of 19th century and through to the 1960's. Up to world war II it was also used in photographic studios, was the It is a chemical mixture of a strong oxidizer, such as potassium permanganate (KMnO4), and a fuel, such as aluminum or magnesium. Both compounds, usually in proportion 70/30, must be in powder form, aluminum can be bought as such while potassium permanganate has to be crushed into small grains in a mortar, and completely dry. 1 gram of flashpowder has an approximate guide number of 35, and 50 grams, as can be computed from the section on multiple electronic flashes, a guide number of 250.
Figure 14: View of the rapids, river Rak above the cascade in Planinska jama cave, Polona, Graflex Crown Graphic Special 4 x 5 inch camera, Schneider Xenar 4.7/135 lens; illluminated by 50 g of flash powder from behind the rock at the right, f 22, time T, Kodak Vericolor II type L sheet film, ISO 80; 1981
50 grams would be enough to illuminate a motive of light colour at a
distance of 30 metres with the aperture value of f 8.0, in a darker
cave, such as in Figure 14, at some smaller distance. The light source,
as already mentioned at the beginning of this paper, is very large,
from one to two metres, gives very gentle and soft shadows,
takes about two tenths of a second to burn and is therefore most
suitable for photography of flowing water.
Flashpowder, however, is also not flawless. First of all, it is this area of pyrotechnics that is very dangerous. Compounds are highly reactive and require extremely careful handling, if possible not in closed spaces but outdoors and far from heat sources, sparks or, god forbid, open fire. Ignition of flashpowder is not particularly simple, especially if pollution of cave floor is to be avoided. Also, the smoke and the fog, which develop after ignition are a great disadvantage (flashbulb filament burns inside the bulb and the smoke remains in it). It is almost impossible to repeat the shot and searching of the exit from the hall often resembles mission impossible. Since the whole procedure is not environment friendly, cave animals do not enjoy the smoke, the decision to use flashpowder must be very well grounded. Usually it is used when the hall is very large, very dark, well ventilated and when it is evident that a good cleanup is feasible.
More can be read in older books on speleology and caving; in Slovenian, it is the Jamarski priročnik, chapter on cave photography by Franci Bar. The book was edited by Ivan Gams and published by Mladinska knjiga in 1964. Some info can also be found on the Internet, useful pages are for instance http://krimzonpyro.com/ep/infodir/compoDB.html#chapter6 (Wouter Visser, http://www.wfvisser.dds.nl) or the page, prepared by Dennis Fritsinger: http://www.totse.com/en/bad_ideas/ka_fucking_boom/chlorate.html.
Besides the usual methods for the illumination of cave photographs, there are of course other possibilities, undescribed until now. At close distances, quite useful pictures can be made using carbide lamps (Figure 5) or even candles, yet, at further distances, some clean and environmentally friendly alternative technology is not commonly known.
Figure 15: Dripstone wall at the beginning of the water gorge, Boni; Canon EOS 300 D, f 8, 30 sec., ISO 400, white balance set to incandescent; illuminated by 2 kg of hay at the right, 1 kg of hay at left; Vodna jama v Lozi cave, March 2004
But alternative methods poped up quickly after a visit
to a chemicals store, in order to buy, after several years, a new supply
of ingredients for flashpowder. Now, you are told that things have
drastically changed because of junkies (potassium permanganate can
supposedly be used as a compound in making drugs) and worsened security
situation in the world after tragic dates such as March 11, 2004 and
September 11, 2001. In order to purchase flashpowder ingredients a
special permit is required. One has to write an application to the
relevant state authority with detailed and convincing argumentation
for what reason the chemicals are necessary, pay an equivalent of 20
US dollars and wait for at least one month to receive an eventual
positive answer. After that the store will order the chemicals from
the central depot (times when the store used to stock them are long
gone) and after several more weeks of waiting, there will be no further
obstacles to the preparation of flashpowder. So it would not be so
strange if someone would say: 100 years old technology for cave
illumination (and photography) is no longer feasible, so let us try
out the 200 years old technique. If the ancient cave guides such as
Luka Čeč could illuminate the cave for distinguished guests with some
handfuls of straw around 1800, the method probably is worth a
try. It works indeed, the light is very warm, about 1,700 deg. K,
gives most romantic effect (Figure 15) but pollutes even more than
the flashpowder. There are not only ashes that fall off during burnout
but a cloud of smoke with ashes lifts towards the cave ceiling, cools
down there and an ash rain follows, like after a volcano eruption.
So the method is unsuitable for pristine cave environment; maybe some
day a better, clean procedure can be invented.
In the end, the use of available electric illumination remains to be discussed, especially in showcaves where photography, using a tripod in particular, is not forbidden. This method is most comfortable: The photographer walks on the paved path, picks a motive, mounts the tripod, sets white balance and focus to auto, exposure to program (P), turn the self timer on (not to shake the camera while pressing the shutter release), walk to aunt Rosemary, nicely put to the fence, check her bonnet briefly, hug her around the shoulders and click! The picture has been made. If you manage to set aside some more travel money or if there is some other business to be done in the Republic of South Africa, it is well worth visiting Cango Caves. Photography is allowed and speleothemes, up to 20 metres tall, are illuminated in various colours for really picturesque photographs: some in blue, some in red, some in green.
The selection of a camera for cave photography is not as difficult as expected. On one hand, it depends on the weight of the photographer's purse and, on the other hand, on how many pictures are to be taken and what those pictures will be of. For documentary photographs without special lighting effects and for distances up to several metres, the range of the built-in flash, the most accessible cameras will do the job. Camera choice is big; besides well known makes such as Canon, Nikon and Fuji, there are many other brands with decent models. Such cameras are lightweight and small, they fit nicely into the inner pocket of the over-suit and, in the worst case of loss or breakdown no costly damage can occur. For more upscale intentions and not exactly the least expensive solution some moderately priced camera with a hot-shoe mount on top is recommended, such as Sony DSC V-1 or a second-hand Canon G3, G4 or G5.
If you aspire to pursue more serious cave photography,
there is a dilemma over which type of camera to use: either
a compact digital camera or a SLR (single lens reflex) digital camera.
Both types have a lot of pluses and minuses. Compact cameras are slightly less
expensive, still very small and light they fit well, if not in the
pocket, then under the over-suit, above the waist, even with an
additional mid-size flash mounted. Oversuits are usually loose at the
waist and I added an extra leather belt above the oversuit
to prevent the camera from moving down towards the knees.
Compact digital cameras already have manual setting of all parameters,
aperture (starting at f 2.0 to f 2.8), time (usually up to 8 seconds
and B), distance and, of course, the white balance.
In cave photography, the lack of exchangeable-lens feature is of lesser
importance than the wide angle side of the zoom, which is used most of the time.
The main disadvantage is the optical viewfinder; display on the camera's back,
unfortunately, is of little use for cave picture composition.
If the compact camera is furnished with a traditional tunnel-type
viewfinder, it will show even a very dimly lit picture, for instance, a cave
scene illuminated only by a carbide lamp, but not the entire picture,
only about three quarters of it - an extra quarter, mostly in the upper
part of the frame, gets captured but is not seen. This fact makes
precise composition rather difficult, and it is often necessary to
repeat the picture for correction. Compact cameras with an electronic
viewfinder show almost the entire picture (95 % to 97 %), but with
annoying delay, induced by LCD technology and show the picture only if it is rather
bright. In a hall (even a tiny one), illuminated by a carbide lamp, almost
nothing is visible in such a viewfinder and, to estimate where the
borders of the frame are, the camera must be tripod mounted and a
light source (lamp on the helmet will do) ported around the scene.
It works well for left, right and down (floor) but worse for up
(ceiling). Compact digital cameras have another advantage, though: the
height/width ratio, which is 3/4, a most reasonable ratio for taking
pictures of cave tunnels; they are usually more wide than tall.
At the time this article was written, there were 5 representatives of the new 8 megapixel wave of compact digital cameras: Canon PowerShot Pro 1 (28 - 200 mm equiv., f 2.4/f 3.5, to 15 sec.), Konica Minolta DiMAGE A2 (28 - 200 mm equiv., f 2.8/f 3.5, to 30 sec. and B), Nikon Coolpix 8700 (35 - 280 mm equiv., f 2.8/f 4.2, to 8 sec. and B), Olympus C-8080 WZ (28 - 140 mm equiv., f 2.4/f 3.5, to 15 sec. and B), Sony DSC-F828 (28 - 200 mm equiv., f 2.0/f 2.8, to 30 sec.). They all have the same size sensor (6.6 x 8.8 mm, 2,448 x 3,264 pixels), an electronic viewfinder, a hot-shoe external flash mount and all but Canon (2.0 inch) an 1.8 inch LCD. Prices vary around $ 1,000 (US street price), the weight inc. battery goes from 512 g (Nikon CP 8700) to 906 g (Sony DSC-F828). There are plenty to choose from, and all can be expected to deliver good service.
Besides the listed compact cameras with a wide targeted audience of more demanding, prosumer (professional/consumer) users, there is another model, for the connoisseurs. It comes in two flavours, the first being Leica Digilux 2 (around $ 2,000), and slightly more accessible Panasonic Lumix DMC-LC1 (around $ 1,500). The two cameras have a digital heart, but a traditional, film soul. The sensor has 5 mil. pixels (ratio 3 : 4), the lens is Leica DC Vario-Summicron f 2.0/f 2.4, 28 - 90 mm equiv., the longest exposure time 8 seconds. Zoom, distance and aperture are controlled by rubber rings on the lens body, and exposure times by the rotating knob on top of camera, just as in all good film cameras. Electronic viewfinder and the LCD both show 100 % of the picture taken and, the best of all, LCD has a 2.5 inch diagonal and a surface of 16 square centimetres, twice as much as the digital compact and SLR competition (1.8 inch diagonals). Cameras for those who want to see how the picture really looks.
The other possible solution to the camera type dilemma,
feasible after September 2003, is a single-lens-reflex
digital camera (SLR). These cameras differ from compact digitals in
many ways, most of all they resemble much more of the "real" traditional
cameras. They have a mirror that reflects the image from the lens, over
a pentaprism, to the viewfinder. The viewfinder is therefore very
bright; it covers almost the entire frame (97 % or 98 %). It is an
excellent aid to set the distance manually using the ring on the lens.
Because the zoom is also regulated by rotating a rubber ring on the
lens and because the display on the back cannot be used to frame the
picture (it serves only for checking the picture after it has been
taken), digital SLRs consume very little power. A single battery is
enough for 100 or more pictures, definitely enough for at least one
excursion. Such cameras also cannot film short movies,
a standard feature of compact cameras, but they do have exchangeable
lenses. If the user has a traditional SLR outfit with several lens of
the same brand, they can also be used, more or less, on digital SLR as
well. This feature is not of particular importance in cave photography,
because, on one hand, there is considerable danger that the camera sensor
will get polluted by dust particles during changing of lens in dirty
environment and, on the other hand, as already stated, for most pictures
wide angle setting of the supplied lens is quite satisfactory.
Other true advantage of SLRs is the sensor itself; it is by an order of magnitude bigger, usually it is 16 x 24 mm or close to this value. The light recepting cell (that covers one pixel) of a better compact digital camera has, for instance, the surface of 7 millionths of a square millimetre (6.6 x 8.8 / 8,000000), compared to 61 millionths (15.5 x 23.7 / 6,000000) of an average digital SLR. An immediate consequence of this fact is that every cell gets much more light and can therefore register colour values of the light it received much more precisely. The image is thus much softer and closer to the real thing, as it does not require the application of strong interpolation algorithms for artificial sharpness, which are a must in compact digital cameras. This is why the digital SLR image is also much more comparable to the picture obtained by traditional film cameras; film still has better tonal range and can preserve more details in the shadows and in the highlights. According to some authors such as Ken Rockwell, 35 mm film picture contains 25 mil. pixels of data, medium format picture around 100 mil. pixels and a 4 x 5 inch sheet film about 500 megapixels.
At the moment there are two digital SLRs available at a reasonable price. The first was the already mentioned Canon EOS 300 D (2,048 x 3,073, 18-55 mm equiv., f 3.5/f 4.5, 30 sec. + B, $ 1000 with lens). It established itself very well after release on the market in September 2003; it was the first SLRs to be advertised in wide circulation non-photographic magazines such as Time. Following the principle Gdje je vojnik, tamo i desetar (in Serbian, in English it would be Where the soldier, there the corporal) Nikon moved in half a year later with the model D 70 (2,000 x 3,008, 27 - 105 mm equiv., f 3.5/f 4.5, $ 1300 with lens, sensor 15.5 x 23.7 mm, multiplication factor 1.5, ISO 200-1600). The basic advantage, as far the cave photography is concerned, of the Nikon D 70 over Canon 300 D could be, besides radio controlled flashes SB 800 and SB 600, which are discussed later, manual distance setting. On Canon's kit lens, it is done with a ring on the front side of the lens, which is very narrow, rotates only a light front part of the lens, and comes without any scale in metres or feet. So there are three ways of focusing the cave scene with Canon: using autofocus on any important part of the scene which is well illuminated, manual focusing on the helmet-mounted light of the extra (figurant) or by manually focusing using a rule of thumb, as Alojz Troha from Križna jama cave would put it: rotate the focus ring to the end (infinity setting), return the ring a little backwards and that's it.
D 70 kit lens (18 - 70 mm) has much wider rubber focusing ring on the back side of the lens and has a window with marked distances in metres and feet (yet with just a few figures from 1 m till infinity). If there is no flame or other source of light in the picture which would help in focusing but the distance can still be estimated at, say, 5 metres, it can be set to this value on the lens and all would be fine. Alternatively, setting a distance to a given value comes in handy during the shooting of portraits. Many of us who shoot a lot of portraits, dislike the idea of people having bigger or smaller heads in the picture when they actually do not. So it is convenient to shoot portraits always from the same distance, say 1.6 metres on lens with a focal distance of 100 mm on a traditional SLR. The distance is set to 1.6 m and the camera is moved away from or closer to the person until the face is in focus.
For photography outside caves, on the surface, Nikon D 70 has another advantage of fast flash synchronization time, up to 1/500 sec., while Canon 300 D can only synchronize till 1/180 sec. A drawback for Nikon, besides weight (D 70 with kit lens weighs in at 1.069 kg, while 300 D is much lighter at 0.835 kg) is the sensitivity: it starts at ISO 200 for Nikon and at ISO 100 for Canon, a considerably more enlargement-friendly value.
Figure 16: A bovine heart-shaped stalagmite with curtains on the passage to the upper part of the Habib Bourgiba Hall in Grotte de la Mine cave, Dondon, Walid; Canon EOS 300 D, f 8, 1/60 sec., ISO 100, white balance set to "sunny"; illuminated by a full strobe from the Nikon SB 28 flash; Tunisia, January 2004
And what are the flaws of digital SLRs when compared to compact digital cameras? Besides weight and bulk it is primarily the picture height : width ratio. It is 3 : 4 in compact cameras and 2 : 3 in SLRs, the same as in traditional film SLRs. If taking a panorama of a hall or if the height of a shaft has to be emphasized, the ratio 2 : 3 is fine, but for an ordinary gallery, which are usually slightly wider than they are high, the ration 3 : 4 is really better. An additional drawback is the depth of field. Compact digital cameras usually allow the usage of aperture value f 2.8 because their wide angle focal distance of 7 mm (28 mm film camera equivalent) sports a marvelous depth of field, from about 10 m to infinity. To get the same depth of field on a digital SLR, where wide angle focal distance is 18 mm (again 28 mm film camera equivalent) the aperture has to be closed to at least f 5.6. This is not so bad, though, because SLRs have much larger sensor and sensitivity of ISO 200 or 400 is quite acceptable, with little noise, which is not the case in small sensors of the compacts; f 5.6 at ISO 400 equals to f 2.8 at ISO 100. The other side of the SLR zoom range, 55 mm at 300 D and 70 mm at D 70, can also be put to good use while shooting portraits. The picture of a clearly outlined face with a vague background of hills, a landscape or a cave is much nicer than a sharp face on an (almost as) sharp background.
A camera's built-in flash can only be used at short distances,
so an additional light source is required for cave illumination,
in most cases an additional electronic flash. The standard heavy weapon
is the Metz Mecablitz 45, with the servo flash trigger Metz Mecalux 11.
There are many versions of this flash but all have a guide number
of 45 (ISO 100, 35 mm lens equiv.), so the least expensive version,
CL - 1, will suffice; the light diffuser for 28 mm equivalent lens is already
mounted on the flash head. It weighs almost one kg but will recharge
fast after a full strobe - in 8 seconds with Metz NiCd battery and in
12 with 6 NiMH AA cells. There are other, presumably more powerful
models such as Metz Mecablitz 70, but here a guide number 70 is only
valid for a film lens focal distance of 105 mm, at wide angle of
35 mm equivalent GN is less than 50.
The other possibility are flash units which can cooperate very well with the camera. They must be the same brand as the camera and are at least as expensive as the Mecablitz 45, but with only about one half its power. Good examples are the Nikon SB 800 (guide number 36) and SB 600 (GN 30): they are capable of wireless communication and data exchange with one another and with the camera's built-in flash, of Nikon D 70, for instance. This compatibility is far reaching. The camera's built-in flash can be used as a control unit for other flashes even if its strobe is turned off. The flashes measure reflected light in real-time and report the values to the camera, which is using them for analysis and determination of proper white balance and for decisions about when there is enough light from particular side and when the relevant strobe can be cut short. The whole procedure is interesting because colour temperature of a flash strobe is falling with time - short strobes are more blue while the long ones tend to turn downwards to the red region of the spectrum. In comparison to Mecablitz units these flashes do not need servo release boxes; they are half the size, half the weight and are powered by 4 AA cells (instead of 6).
At the end a general remark on electronic flashes - their condenser and rechargeable battery grow weaker with time and will eventually die out if unused for longer periods of time (condenser in several years, battery in several months). So, it is wise to do a maintenance check at least once a month.
Not only camera and external flash units, some additional gear
is required to fill up the transport bag. Number of tripods depends
on how many helping hands there are on a photo excursion. If there
are some additional people, one tripod will do; if not, more tripods
will be necessary. It is, however, difficult to
carry and handle more than three tripods. Tripods must be lightweight
and high, ideally extensible to the height of 150 cm; it is also
important that the tripod head is equipped with a quick release plate
so that the camera can be mounted and dismounted easily and that the
knee joints are locked into place with a handle and not with a screw;
mud and screws are not a very good combination.
For photography in water caves, a pole or a long wooden cane, 2 to 3 metres long, is also recommended. The water in the lakes will be vivid green if illuminated from the top, the higher the better. The height, of course, should not be too great, otherwise the effect of the strobe will be too weak.
And, last but not least, some worthy discussion about the photographer's personal caving equipment. A carbide lamp is not ideal, it is inconvenient to turn it off and on frequently. I use a 12 V, 5 W halogen electric bulb in a small casing (originally intended for display window illumination), mounted on the helmet and connected to a 1.8 kg gel lead acid battery, ported in a small backpack. It lasts 8 hours, with some economization even more. LED-based headlights, such as Tikka by Petzl, are too weak (in 2004) for proper illumination of the motive and are also insufficient for safe movement around the cave, especially if one is burdened with all kinds of photo gear.
The team is one of the few very serious problems in cave photography. Unlike the photography in most areas of natural sciences, where the photographer can work solo, the situation underground is much different. Botanists for instance are very happy; it is possible to photograph flowers from all sides, if there is no available light by using a flash, and they are even more happy because flowers do not run away - which is a great problem for zoologists. Pictures of mountain peaks, landscapes in all four seasons, details of ice, river sand, rapids, all this you can photograph alone, in peace, with no one to say: Why have we stopped again? Is it necessary to take a picture right here? I will not stand in this mud. Have you looked on your watch? and so on, and so forth. The idea to take pictures during some other cave work, for instance while accompanying a research or a topographic team, really seems tempting, but it turns out that it is as feasible as a wooden iron. More about this experience later on in this chapter.
Cave photography in solo version should be undertaken only
as a last resort, when everything else fails. For instance, if it is
Sunday afternoon already and no cave picture has been made for two
weeks or if the companions let you down in the last
minute, say because of vis maior. You have practically arrived,
the cave is quite near, cell phone signal is weak and the message that
their car broke down has still managed to get through ... It is
not recommended to go caving alone because if you get stuck in the chimney of
Mačkovica cave or if the lamp fails or if you just make a wrong step
on the slippery passage to Mala dvorana hall and twist your ankle,
who will rescue you? Who will go for help? There is no phone
signal underground ... It is therefore wise to limit the choice to
some well known easy cave, where one can wait for several hours until
search-and-rescue mission arrives.
Cave entrances are a good target - the path to get
there is always interesting and their look is different depending on the season.
The solo photographer can also act as the extra in
the picture, using self-timer and some tripods, usually three: one for
the camera, two for the flashes that provide left- and right-
illumination. If the looks of the photographer are not quite desirable,
it is possible to show the camera some less
problematic body part, like the back, for instance.
Solo cave photography can be quite an adrenaline rush, running with some poor light from the camera after the self-timer release, over the rocks, water and other obstacles to the extra's position, to cool down there and take a proper, loose stance, all in just 10 seconds. Setup of the flashes also takes much more time solo, there is a lot of jumping between the tripods and half an hour for a slightly more elaborate shot is not much. For solo cave photography, it is wise to go on plain terrain, with a good sense of measure (even better than when going solo in the mountains) and with few expectations. Nevertheless, some useful picture may still come out of it (Figure 13).
Going as a couple is infinitely better than going solo on some excursion (not only into caves of a south sea island). For some occasions taking pictures in a pair can be the best choice. The photographer and the extra both mount the tripods and flashes, they both decide if the shot has to be repeated. The work is not boring, time flows by unnoticed and the pictures can be very pretty. Most shots can be done from hand, without a tripod for the camera. Most effective entrance shots are from inside of the cave looking outwards, and they usually require only one additional flash on the camera for softening the high contrast and filling the shadows. More elaborate pictures deeper in the cave are also possible from hand, with three flashes: one on the camera, for triggering the slave sensors on other two flashes and for killing very harsh shadows, the second one from the side, on a tripod, to add plasticity and depth to the picture and the third flash, also on a tripod, for illumination of the background or for adding contrejour accents (Spitzlichter in German) to the main motive.
Figure 17: Ana A'eo cave - view from the centre of the hall towards the eastern side of the entrance, Nadja; Nikon CP 5000, f 2.8, 1/500 sec., ISO 100, white balance set to "fine"; illuminated by available light and one full strobe of Metz Mecablitz 45, island Rurutu, February 2003
For photography in a pair similar precautions are valid as for solo excursions - it is better to choose easier cave parts, even simple shafts and longer water sections can be very risky. Large halls, which require multiple strobes, are also too difficult for two. Even if it is possible for the photographer to run away from camera and fire additional strobes from one side, the extra cannot help him from the other side; he must stay fixed on his position or he will become a ghost, a translucent, ethereal figure. The strobes the extra (and the photographer) have produced after leaving his place in the picture will illuminate that part of the scene, this time without him. Fortunately, there still are lots of beautiful cave scenes, in Slovenia and elsewhere, which are quite suitable for photography in pair.
The ideal team has four members: one at the camera, one on scene, two handling the left and right (or back) illumination. The third additional flash, only used for larger spaces or for special effects, is on a tripod. The work can proceed very fast and even 10 good pictures per excursion are not impossible. In a crew of three, the photographer must also handle one of the additional, off camera flashes. So the camera must be tripod mounted, which takes its time, and there is also much more running around. For larger halls, it is very convenient to have a fifth member of the team, who will take care of the third additional flash.
Figure 18: View downstream the Jezerski potok towards the speleothem Sladoledni kornet (Ice cream cone) in the 12th lake of Križna jama cave (part); Canon EOS 300 D, f 8.0, 1/60 sec., ISO 400, white balance set to "sunny"; illuminated by Nikon SB 28 flash on camera, 1 x Mecablitz 45 from the right (out of a boat), 1 x Mecablitz 45 from the left (from the river bank); December 2003
Special task: photography in water caves, the queen of which is Križna jama cave. Illumination posts often cannot be placed in the location required to provide ideal lighting for the picture; instead, the location of the posts will be determined by a compromise between what lighting the picture requires, which locations are physically possible and which locations will best protect the fragile river banks and river bottom. Ideally the photographer is in the first boat, the extra in the second, the assistant for side illumination in the third and the assistant for background illumination either ashore or in the fourth boat. Some more crew is necessary for rowing; boats, left unattended even for short period of time are quickly whisked away by the current or at least rotated by effects of their previous movement. The picture-taking procedure is not at all simple. With such large fleet, the voyage to the part of the cave where the photo action is to take place would take too long, so the smallest boat either has to be loaded on some other boat or inflated on scene. In the case of Križna jama cave there are two mitigating circumstances, the first being the extraordinary beauty of the cave which makes any business more pleasant, and the other is a very skillful and careful manager of the cave, he deserves to be decorated for special merit. To have a partner such as Alojz Troha is any photographer's desire.
Figure 19: Testing of the new boat in the first lake of the Rakov rokav, Planinska jama cave, Barbara and Ines, Nikon CP 5000, f 2.8, 1/50 sec., ISO 160, auto white balance; illuminated by Nikon SB 28 flash at full power; June 2003
The situation is different in caves without such goodies as in Križna jama. In a water cave with walls dark as in Planinska jama the team of only four in two boats has to focus on one or two pictures and hopefully some other good one pops up unexpectedly down the road.
It often happens that the photographer joins the excursion with non-photographic goals - an exploration, measurement, digging or just sightseeing team - if for nothing else than for company and to stay fit. To leave the camera back home would be too harsh, maybe the cave ghost will reveal himself exactly on that occasion, but to slow down the colleagues and poke at their nerves with serious photography, is also not an option. So the decision falls somewhere in the middle: make do with handheld documentary shots, say with an additional flash mounted on the camera at all times, both hidden from sight on the inner side of the oversuit. Friends will be fond of such pictures, even if the pictures carry no special weight, they will be good enough for fun and entertainment. Most photogear can stay at home, with the exception of a small tripod and two external flashes.
Figure 20: Boni at the entrance of Lupertova jama cave, Lanski vrh near Laze, Canon EOS 300 D, f 5.6, 1/50 sec., ISO 200, auto white balance; illuminated by available light and the built-in flash; October 2003
I took part in the excursion at Ocizeljska jama cave just before
New Year 2004, mainly to practice the single rope technique which, to be
frank, is not exactly a pleasant or delightful task. It could only
be a source of joy for Matija (Perne), many of us are green with envy
when watching him move up or down (or any other direction on) the rope.
The gear still filled a voluminous backpack; it went down quite well
but much less so upwards - without Gregor's helping hand a
photographer's life on return would be a real misery. The cave is long;
shaft after shaft, the members of a new caving school course
brought the total crew count to 15 and the time was flowing by
mercilessly fast. Franček was leading the excursion, he took great
care that all ran smoothly, as it should, and he was quite successful in
rejecting some transparent maneuvers from my side to the tune of:
I would like to see just this side-tunnel and two teammates could
join me. But as the excursion drew slowly to a successful end,
when there were only Gregor with his son and daughter, plus Franček
and a more and more melancholic figure of my humble self, at the bottom of
the first series of shafts, the leader showed his more understanding
side and asked: Might we make some bigger photo at the end?
It was, of course, as if someone had asked the frog if it would like to
jump into the water and the picture on Figure 26 was made in 10 minutes.
It happens very rarely that an excursion will end with no picture having been taken, and that the outcome can still be considered a success. Sometimes it takes all the strength one has to pass a narrow squeeze, even without extra gear. And if you happen to be invited to visit the new parts of the western gallery of Predjama cave system (or some Welsh cave), and you do not have a small camera in a waterproof box, and Bojana, who lives nearby, makes a hint that it would be wise to leave the camera and other gear before the water barriers and squeezes (Ivo said most convincingly: It is nothing particular, the water is as high as the rubber boots, you just run to the other side quickly and you do not even get wet, a neoprene suit does not make sense, while climbing the traverses you could get a heat stroke ...), follow the advice without further discussion. When you find yourself in a hidden pool waist deep in water, and the water is even deeper to your left and right, or when you wonder, lying twisted in an oblique crack with a small stream at the bottom, that it would not be such a bad idea to have a rib or two removed, like Cher the singer, it will be too late. Even thoughts of return will not bring any comfort (there are no shortcuts in style of the PTKRF magic word which would bring you to the surface from the depths of the labyrinth in Treasure text computer game on DEC-10 mainframe) and to find yourself again on the lawn at the cave entrance, below the clear sky, will be nothing but a pure joy.
Feeling good and proper motivation of all participants, be it solo or during a large photo excursion, is an absolute necessity. If any single teammate is in bad mood, if he cannot be amused, the whole session has to be shortened, the nerves become tense and all the effort is in vain. So it is up to the photographer to do all in his power to make the team comfortable. Not many nature photographers got rich and, as far as it is known, definitely not with cave photography, despite the amount of work the goes into every underground picture before it is made. It is very convenient if the participants of a photo excursion are unfamiliar with the cave or the cave part - everything new is always interesting and more attractive. The importance of the extra for the success of the picture is however critical.
Figure 21: Grega helps Andreja climb out of the chimney in Mačkovica cave, Nikon CP 5000, f 2.8, 1/60 sec., ISO 100, auto white balance; illuminated by Nikon SB 28 flash; March 2002
The most perfect shot, with ideal composition, gentle and just right illumination, can be thrown away if the extra looks like a pile of bad luck. Beauty and youth are not be underestimated, but good will is worth even more. A combination of all three, with emphasis on good will, is the true recipe for success.
If the photo procedure in traditional photography more or less ends with making prints or developing slides and an eventual entry in the photographer's log book, in digital photography there are several other tempting paths to follow. As it is possible to project the slides onto large screen and show them to a big audience, the same can be done for digital images with an LCD projector. Such projectors are expensive, but becoming more and more widespread, and it is not so difficult to borrow one; there are also some lecture halls where an LCD projector is already built-in.
The story does not end here. Today, presentation of pictures on
Internet is a wide reaching, very popular method of publication. The
road to internet publication is very short for digital pictures. The costly and time
consuming scannning of photographs and slides is not required. All we
need is a graphic program for reduction of picture size (a very useful
one, freely available at web address
written by Irfan Škiljan), an editor for web page composition and,
last but not least, a space on some web server, such as www.speleo.net
of Društvo za raziskovanje jam Ljubljana. When the camera card gets full
or on Sunday evening, whichever comes first, the pictures are
transferred to computer, renamed with proper serial numbers, and prepared
as reduced-size copies with picture descriptions added to the machine-generated web
page. The page and the pictures are transferred over the network or phone
lines to the server, and all concerned cave-lovers are notified via e-mail.
That's it! Examples of such pages, made by the author, can be
checked at the web address
Besides such presentation, where the pictures are usually set in chronologic order, it is also not difficult to make a picture search page, where it is possible to query using words from picture descriptions. An example, also by the author, is the web page http://bos.zrc-sazu.si/telri (write jama into the search window and see what happens ...).
The only major nuisance to all this digital photography,
one of the big problems,
virtually unknown in traditional photography, is the abundance of
pictures. As it is impossible to eat too much fruit, it will just not
go down when there is enough, there are seldom too many prints and slides;
the price of film, development and everything else kept
quantities at reasonable limits. In digital photography, things can
quickly get out of control. The world is beautiful, there is
constantly something going on and to press the shutter release hundred
times a day is also not particularly difficult. The storage card
diligently keeps it all, and then ... the guilty conscience steps in.
To let the pictures lie there just like that is a shame. To process
them, add text descriptions, put them on the server is ideal, but
it is a lot of work and more pictures take even more time. Backlog
quickly starts to build up, some pictures get done, some are left behind,
in style of: I will manage, if not this week then the next one.
Time goes by mercilessly, new pictures keep coming in, old ones fill
the computer disk, they are piling up on CDs ... and slowly move
to the garbage dump of history. The serial number of my last
digital photograph, at the time of writing these lines, was 9100.
Around 3400 have been processed and 5700 are waiting for better times.
So it is better to be disciplined, to shut big eyes a little and to think twice at every scene: Is the picture worth it? Is it beautiful enough to get exhibited? Would it not be better to live on without it?
Another problem, related to the presentation of photographs on the Internet, is the possibility that your author's rights will be violated. Photographs are the author's work, and like any other intellectual property, it is yours from the moment it has been created. Yet, it is difficult to protect a photo web presentation from unauthorized use, to navigate between the Scylla of users with good intentions and the Charybdis of Internet thieves who steal everything that is not nailed down and sell it merrily as it would be something they made themselves. It is far more pleasant to watch full-screen sized photographs, 768 x 1024 pixels or at least 600 x 800 pixels than the small ones, which load much faster, especially if the spectator is connected to the Internet over a phone line.
Figure 22: Marjan descending in the entrance shaft of Jama na meji cave, Canon EOS 300 D, f 8, 1/15 sec., ISO 200, white balance set to "sunny"; illuminated by a full strobe of the Nikon SB 28 flash; February 2004
Therefore, it is common practice on the Internet to show small versions of the photographs, say 300 x 400 pixels, and a line of description, with a hyperlink to a larger, full-frame image that users can access by clicking on the small picture with the computer mouse. An example is the following code in the HTML language, related to the presentation of the user's photograph number 6041, from Križna jama cave, January 2003 (taken from the web page http://www.jakopin.net/primoz/slike/2003/030111.html - in Slovenian):
<p align="center"><a href="./slike/pj06041b.jpg"> <img src="./slike/pj06041c.jpg" width="400" height="300"></a><br> 6041. Speleothemes on the right bank, before Kalvarija</p>
The 300 x 400 pixel picture, stored on the server disk as the file pj06041c.jpg,
is shown immediately; a click on it displays the same
picture, this time stored as the file pj06041b.jpg, with 600 x 800
pixels. However, it is true that there are many who
think of the Internet in the way picturesquely described by Ivo Lučić, a
journalist from Zagreb: Internet, pa to vam je samoposluga
(Oh, Internet, it is a self-service grocery store). They pay no
attention to the fact that the page is intended for personal use and
that copying or other manipulation of the information
is not allowed without prior consent from the author.
A typical abuse is installation of your pictures on other web pages,
usually without explanation and, of course, without permission.
It is also a very clumsy compliment to the author if he finds out that
his photographs, taken from Internet, have been published in a foreign
newspaper under some other name.
There are several ways to defend oneself: The most radical and completely effective way is to avoid any web presence; the less extreme solution is to publish only small pictures, say up to 300 x 400 pixels; the more generous approach is making full-screen size, lower grade pictures available but not the higher quality ones. For about a year now, I have been using a combination of all three options.
There are some other traditional ways to present the photographs, besides lectures and the Internet. People love to read printed media. However, magazine and newspaper editors prefer complete articles, and photographs alone are less likely to get accepted. If you are not particularly versatile with a pen, it is best to find a matching soul who likes to write but is not a keen photographer; such combined efforts are often very successful. If some cave or cave topic is very close to your heart it is worth while to take the time, perhaps a few years, to collect more material and to publish a monograph. Many large and important caves lack one, so there is ample opportunity for such projects. The third possibility is an exhibition. Select 20 good photographs with some common denominator, and have prints made. From a 5 million pixel file (3 : 4 ratio) acceptable enlargements up to 70 x 90 cm can be produced, from a 6 mil. pixel file (2 : 3 ratio), enlargements up to 70 x 105 cm. There are quite a few laboratories where good prints, even on canvas, can be ordered at a reasonable price. Find a wood craftsman who will make you inner and outer frames, mount the canvases and there you go. Photographs on canvas, 60 x 80 cm, with a suitable, not just minimal, frame weigh 1.25 kg. 20 exhibition-ready pictures at just 25 kilos are easy to transport around, even in a standard car. Exhibition, especially the opening, is a great festive day, a unique event which brings a lot of joy not only to the author, but nearly always to the visitors as well.
Photography and photographs are nice. It is a quick and
efficient way of expressing oneself visually. There is a painter
hidden in all of us, but very few have the artistic urge and such an
extraordinary dose of talent to pursue a career in beaux arts.
This is why photography is usually treated, well deserved many would
say, as a very mundane and non-artistic business, to the tune of:
Anyone can press the shutter-release button. There are few notable
artists in the field of photography worldwide, and many fine
photographic opera go by virtually unnoticed.
It is possible to add a different touch to photographs, using various postprocessing techniques, to make them more acceptable to the choosy audience. There are many filters available with most graphic editors, and the results can sometimes be quite pleasing.
Figure 23: View out towards the middle of the hall, Side hall in Rača špilja (Rača cave), Lastovo island, Canon EOS 300 D, f 8.0, 1/30 sec., ISO 200, white balance set to "sunny"; illuminated by Nikon SB 28 flash from camera, Metz Mecablitz 45 1 x close from the right and 1 x from the Entrance hall at left; August 2004
The image in the Figure 23 has been obtained through a modification using Microsoft Photo Editor. In the Effects menu, Texturizer tool has been selected with the following parameter values: Type had been set to Sandstone, Light position to two o'clock, Scaling to 100 % and Relief to 10.
As with every other cave activity, photography must be carried out
in such a way that there is as little damage to the pristine cave environment as possible.
For this reason, electronic flash is used as a primary light source, and
other methods of large scale illumination should be avoided. The
locations of lighting assistants should be selected with care, not on
soft or vulnerable surfaces. Mud should not be ported to dripstone
parts of the cave and shoes or boots cleaned or changed before moving
on to such areas. Walk on cave paths or marked corridors, eventually on
rock base, not on dripstone, clay or sand. Take special care on
underwater surfaces. Loud conversation, disturbing to cave animals,
especially bats, should be avoided. Do not approach the animals, light
is very upsetting for them, too. During the hybernation the bats may
wake up which consumes a lot of energy and reduces their chance to survive the winter.
Caves are also not a place for drugs, even not not even legal ones such as tobacco;
alcohol use should be limited to medicinal purposes.
Views of halls and other spaces are much more interesting if there is some action in the picture. It is also preferable to have some object in the scene for the measure of size, a fellow caver, an extra (le figurant). It is also nice to show in the picture that we, humans, are not the centre of the universe and that the extra complements the cave composition, rocks, speleothemes.
Figure 24: Dripstone wall in Dvorana z velikimi ponvicami above Pisani rov (Gay-coloured tunnel) of Križna jama cave, Tatjana, Nikon CP 5000, f 2.8, 1/30 sec., ISO 100, white balance set to "fine"; illuminated by Nikon SB 28 flash from camera, Metz Mecablitz 45 1 x close from the left and 1 x not so close from the right; January 2003
Ideally, extra is placed in the part of the picture where she or he is not the main attraction and will get discovered only after closer examination of the picture. Clothing and shoes which fit well into the cave environment, both in colour and texture, are recommended. Red or blue oversuits are fine for action shots which depict single rope technique (Figure 22) but they take away, no doubt about it, nine tenths of the glamour to a romantic shot of a beautiful hall such as Dvorana s ključavnico in Zelške jame cave.
When new to the field of cave photography, an aspiring photographer should grab every opportunity to take some underground pictures. In time, personal preferences develop and some genre, in accord with the photographer's other cave activity, will emerge. Speleobiologists will devote a lot of time to animal pictures; cave divers will make underwater images; members of a depth-record attacking team will bring home lots of single-rope-technique related action photographs. Yet a true cave photographer will remain faithful to the field in general and will immediately spot a good cave picture opportunity as the cave and the flow of events on an excursion unfold in front of him. Every genre has its own particular demands and, sometimes, requires special equipment.
Cave flora is very rare and not particularly photogenic, but cave fauna is different, more attractive and more rewarding for photographers. Most cave animals tend to be insects of small size. Proteus, also called olm or human fish (Proteus anguinus) is the most spectacular cave inhabitant, at least in the Dinaric karst, and bats are the most common large-size animals. Although they are not troglodytes, they can also be found in deeper cave areas, kilometres from the entrance.
Figure 25: Lesser horseshoe bat, Rhinolophus hipposideros, on the wall of Lažanski rov in Mačkovica cave, Canon EOS 300 D, f 8, 1/30 sec., ISO 100, white balance set to "sunny", zoom set to 55 mm; illuminated by built-in flash; March 2004
As already stated in the previous chapter, great care must be taken not to disturb the cave animals. So, especially when taking photos of bats, make all preparations for the picture at a safe distance away from them, approach in silence without excessive light, take the picture and leave the scene. Great patience is also required while photographing cave grasshoppers and other flying insects; they will flee or hide themselves at close light.
The following picture, in the style of both the modern sport-and-alpinism laden caving and caving magazine covers (Fig. 26), has been taken by the digital camera, Canon EOS 300 D. It depicts the scene in the hall at the bottom of the first group of shafts in Ocizeljska jama at the village Ocizla near Kozina, during the ascent of Gašper Pintar. Fig. 26 is composed from the following two photographs, shown in Fig. 27 and 28.
Figures 26, 27 and 28: The hall at the bottom of the first sequence of shafts in Ocizeljska jama cave, Gašper; Canon EOS 300 D, f 8.0, 30 sec., ISO 200, white balance set to daylight; illumination is explained below; Ocizla near Kozina, December 2003
Both shots have been illuminated from three sides - 2 flashes from the left (Metz Mecablitz 45, Nada Pintar, close to the rock wall, outside of both scenes), above, 1 flash from behind the upper wall (Unomat B 24, Franci Gabrovšek - Franček) and 3 flashes from the right (Metz Mecablitz 45, Gregor Pintar, in Fig. 27 sitting on the stone pier, still in the scene, and in Fig. 28 sitting on the rocky bench, out of scene). To enhance the contrast and for more dramatic effect the flashgun on the camera has not been used. The camera was tripod-mounted, exposure time 30 sec., f 8.0, ISO 200. Fig. 27 could not be used because the upper right quarter of it is way too bright and Gregor also moved while flashing so that he has two heads in the picture.
Figures 27 and 28
In Fig. 28, taken immediately after Fig. 27, to correct it, Gregor moved back a little, out of the scene and the upper right quarter of the picture is now acceptable. The correction, however, worsened the lower left quarter of the picture, which has fallen out of range of Gregor's flashes and is now too dark. In the final picture, 24, the majority of Fig. 27 has been used. Fig. 28 has contributed the larger part of the right upper quarter, above the wall on which Gregor had been positioned and to the right of the wall which occupies the larger part of the left side in both pictures. The final composition has been augmented by an additional correction - the backpack of the type prasec (hog), which was overlooked on the beach down right and which was of course meant to be out of picture, has been covered with the gravel at the left of the backpack. The procedures have been accomplished with the kind help of Brane Vidmar from ZRC Publishing using Photoshop; the home grown editor (Eva) is not yet suitable for the task.
Even the lousiest cave, čurka in the parlance of author's fellow cavers, is a good backdrop for a cave portrait. And as the gear, elaborate lighting equipment, is already at hand, and assuming the friends are not in a bad mood, some good picture will be taken quickly and easily.
Figure 29: Marinko Malenica in front of the Big white dripstone cascade in the Hidden main channel of Vjetrenica cave, Canon EOS 300 D, f 8, 1/30 sec., ISO 100, white balance set to "sunny", illuminated by Nikon SB 28 flash at 1/8 power from camera, Metz Mecablitz 45 for contre-jour: 1 x from top left, 1 x from middle height right; August 2004
Good viewfinder coverage is essential for portraits, so digital SLRs are best suited for the task. On compact digital cameras, the display on the back of the camera, which gives good coverage (but is less convenient), has to be used. Several portraits are normally taken and the best one selected on scene. The person in the picture is always a very ruthless judge and will immediately tell what to keep and what to discard.
Nudes are a very attractive genre in any branch of art, but not an easy one. There is a thin line between pictures which do justice to the beauty of the human body and images which are just a display of bad taste, where the flesh prevails the form. The disposition of the model is quintessential; she/he must be well aware that it is her/his beauty that counts and this fact should ideally radiate from the picture. A good approach is also to keep things as simple as possible, but still be prepared to spend quite some time and effort to get an acceptable photograph.
Figure 30: A bather from m/b Kristina, Modra špilja cave on Ljuštica peninsula, Canon EOS 300 D, f 8, 1/30 sec., ISO 200, white balance set to "sunny"; illuminated by available light; August 2004
The time, required to take the picture, is a real problem
in the caves of the northern hemisphere where the environment,
especially temperatures (8 - 10 deg. C in non-alpine caves),
are not favourable for nude modeling. More
suitable caves are at lower latitudes, especially close to the sea. The
inner temperature of caves on the islands of southern Adriatic is around 16
deg. C (average year-round temperature on the surface) which can be
tolerated nude for 5 to 10 minutes. Even better suited are water caves on the
coast, such as Modra špilja, where the summer
temperatures of both sea and air get to 25 deg. C. Some tan on the
skin is an advantage, preferably without tan lines left by a swimsuit.
Light, reflected from light-coloured rocks or dripstone, will greatly
enhance the skin tones.
Even if the final result will only end up in some secret family album to preserve the peace of mind of all concerned, nudes are worth the effort. Caves are usually very secluded places without unwanted onlookers and so well suited for such projects. If the photographer and the model are a couple very at ease with each other, taking nudes can be good time and fun.
There are other genres of cave photography not covered here, underwater photography being the most important one. There are fellow cavers with good knowledge and experience in this matter, such as Arne Hodalič.
Cave photography has been a great pleasure to many of us, even in the traditional, predigital times. Nowadays it makes more sense than ever, the little display shows a very reasonable approximation of the picture immediately after the shot and taking pictures has become a pure joy. Although the world depth record, attained at the bottom of Renetovo brezno in the Julian Alps or the first sight of the river, flowing to Boka above the Soča valley, will never be yours, many, including your humble self, will enjoy looking at your pictures.
Figure 31: A view of Svetišče (The temple) in the Putik hall of Najdena jama cave, Luka; Canon EOS 300 D, f 8, 1/30 sec., ISO 200, white balance set to "sunny"; illuminated by Nikon SB 28 flash from camera, Metz Mecablitz 45: 1 x from the left, 1 x from the right, 1 x from behind the pillars in the centre of the picture; May 2004
Darkness in the cave is nothing horrible; it is warm; it is a friend and an ally; within it is hidden the best and the most beautiful for you to illuminate into a wonderful display of colours and shapes. With a little luck, moments of underground beauty can be made everlasting and ported away in a tiny memory card.
This page, text and photos by Primož Jakopin;
send inquiries and comments to
primoz jakopin guest arnes si (insert dots and at sign as appropriate).
Page first posted July 7, 2004 and last changed
November 24, 2019.
URL: http://www.jakopin.net/papers/Cave_Photography/index.php 1399