In my lectures, I often receive questions about the technology and possibility of underground photography. Hence, this article presents an opportunity to regard this problem here. The mirror camera exclusively should be used. The possibilities of the camera do not necessary have to be great. The exposure with constantly open shutter is predominantly used. I use Zenit-19, a camera with wonderful durability - a virtue that is important, considering that the camera is dragged during many hours through the narrow passages. Even after my camera fell in 1989 into a 50m pit, it was repaired during one hour with the help of a screwdriver and pliers. The camera gets out of order, however, after 3-5 two-week expeditions because of the high corrosional activity of atmosphere.

In contrast, the best lenses should be used. Multi-couted lens is necessary, because in all cases, dust and moisture remarkably decrease microcontrast, and all methods of its preserving are needed. A change of lens should be made as rarely as possible because of dust. I use Flectogon Auto MC 35/2.8, which has many qualities. The 35mm focus distance makes it possible to take both long-range and close-up shots without significant distortion. The minimal distance of definition is 21cm, which allows one to photograph detailes without the use of lengthened rings in the majority of cases.

Flashes. All power necessary will not be enough in the majority of cases, and one must photograph only with numerous flashes and open shutter. The time of charging determines the degree of application of the flash. During my last three expeditions I used very powerless flashes (24 joule) with batteries composed of 37 9v elements. With such a technique it is possible to do up to 100-150 impulses per minute. The number of flashes is determined by the number of assistants, but there should be no less than two, though the number of points of light source for the shot should always be no less than four. It is useful to have one flash with a small square reflector for the photographing of small objects. The light-synchronization is very useful in some cases.

The tripod and the photo-rope are necessary, though the stability of the tripod is not a definable factor. The flame of a candle is practically not blurred if one uses a 35mm lens; one can initiate flashes with some delay. The main role for every photograph, even in the case of macrophotographing, belongs to the staging of the shot. First, all possible points of light sources are simulated by a lantern; the reflexes on drops, crystals, and camera optics are studied. Then the route of the assistants' movements through the points of light is analyzed and the number of flashes from each point is counted. Only then the photographing is carried out; moreover, as a rule, there are 2-3 variants of light decision. For the enlivening of the photographs or for the arrangement of still life shots and also of scale, one can use various subjects. The most effective variety such as candle or girl-model called "Gypsum Crystal" in Cupp-Coutunn jargon tend to be overused and lose their attraction. The paradoxical scale samples with living flowers are yet curious.

The care set for the camera is important. Except for brush, bulb, and repair set, the dryer, i.e., the burlap bag, is necessary. The tripod may be covered by the burlap bag, enclosing inside this little tent a burning candle and camera for drying. This is the only way to prevent perspiration between the lenses. It is necessary to have some photo-ropes as well as impulse lamps for flashes Because of the moisture, they easily get out of order. It is important when using a widescreen camera that the film should be placed in a package of silica gel not later than three hours after its removal from the hermetic cover, otherwise, the paper trailer film will fall apart from moisture and will stick in antitwisting layer of the film that will destroy it. The most important role belongs to the carrying case, which has to simultaneously provide a defence from blows during crawling and a defense from omnipresent dust and should be quickly opened. The small duralumin boxes with foam plastic enclosing and rubber thickening of the cover, having some handles and loops on various sides, are optimum.

I would like to remark in conclusion that the presence of excellent assistants is vitally important; without them photography would be impossible. In addition, everybody from speleological circle assists in a good photograph with pleasure, hoping to duplicate a small collection of slides.