FISH, PHOTOGRAPHING This is a branch of Nature photography offer ing a field of peculiarly interesting work. The most important part of the outfit is a good stand camera, with a modern anastigmat, working at f/6. Isochromatic plates should always be used, where possible, in conjunction with a compensat ing filter (isochromatic screen). The size of the aquarium or tank, in which the fish are to be placed for photographing, must necessarily be governed by the predominant size of the sub jects. It is a great mistake to have too large a tank, for it will cause needless labour and trouble, but at the same time it must be kept in mind that unless the fish has ample room to move freely, it will become alarmed, and will certainly assume unnatural positions, while in its struggles to escape from its cramped surroundings it may injure itself. The photographic tank should have all four sides of glass, so as to admit as much light as possible, and one of the long sides must be of good " patent plate " glass free from scratches, air-bells, and other blemishes, which would show in the photograph, as it is through this side that the photographs will be taken. This tank should be kept purely for photographic purposes, and not used as a regular stock aquarium, and must be kept perfectly clean inside and out. Cleanli ness is most important. The water with which the photographic tank is filled should first be strained through a piece of linen, so that there are no floating particles. The fine shingle used for the floor must be well washed before being placed in the tank, to rid it of mud and fine sand. The plants must for the same reason be well washed ; their roots may be cut away, and the base of the stems weighted with a strip of soft lead folded round and embedded in the shingle. It is as well to place the plants rather towards the back of the tank, as otherwise they are apt to get in the way and partially obscure the subject to be photographed. The subject
itself will generally be found to look all the brighter and better for a gentle sponging to clean off any dirt that has deposited in the natural slimy secretion with which the body may be coated. The photographic tank should be placed in such a position that as good top and side lighting as possible are obtained. The camera should be placed directly in front of and at the centre of the long side of the tank that is fitted with the " patent plate." This glass must be perfectly clean and free from smears. It is a good plan to keep a soft washleather specially for the purpose. Instead of introducing plants into the photographic tank, a plain tinted back ground may often be used with advantage. If plants are used, care must be taken to select only those which would be found growing in the favourite haunt of the particular fish to be photo graphed, otherwise a most unnatural effect will be produced. Fanciful or elaborate backgrounds should never be employed, as they only serve to distract the attention from the fish, and pro duce a very artificial effect.
Before attempting to photograph a fish, it should be kept under observation for some time in a roomy, well-oxygenated aquarium, so that its habits and characteristic positions may be studied and noted down. When first placed in the photographic tank, the fish will probably dash wildly about, sink to the bottom, and skulk away into the corners. It is no use at tempting to begin photographic operations until the fish has got over the fright of being trans ferred from the stock aquarium to the photo graphic aquarium, and has become somewhat accustomed to the strong light illuminating the latter. P. M-D.