Photographing Fish And Other Aquatic Life
( Originally Published 1902 )
THE AQUARIUM AND OUTFIT
Outfit required.—Long-focus camera. Rapid lens. Plate-holders. Focussing-cloth. Instantaneous isochromatic plates. Aquarium—two wooden horses ; two boards about seven feet long ; bucket ; rubber tube ; sponge ; cloth (for polishing glass) ; scrub-brush ; claw-shaped tongs ; small landing-net.
UNTIL quite recently fish photography was almost untrodden ground. Few had attempted it, and fewer still had succeeded. The new interest in natural-history subjects, with its absolute demand for "photographs from life," has led, after touching on almost every other branch of work, to the photographing of fish, and almost every month we hear of some person taking it up. Though not so interesting as bird and animal work, it has, nevertheless, many points of interest, and, like all other nature photography, it teaches us a great deal that hitherto has never even been thought of.
The first thing to do before undertaking fish photography is to prepare a special and somewhat elaborate outfit. Besides the camera, lens, etc., there must be a suitable aquarium, and this will have to be made to order. When having it constructed, consider first of all what will be the length of the largest fish you intend to photograph, and have your aquarium at least four inches longer. It is not advisable to attempt fish longer than twenty-eight inches (except such as the garpike or other slender fish), as they are very difficult to handle. The aquarium may be of the portable type, though this has no particular advantage and is seldom water-tight. It is better, therefore, to build one strongly, so that it will not break apart or leak. Then it can be packed ready for shipping by screwing a heavy board over the glass and top.
Good quality of clear white pine is about the most satisfactory wood to use. It should not be less than seven eighths of an inch thick except for a very small aquarium, when half an inch would do. The best way to insure its being water-tight, notwithstanding what the carpenters will tell you to the contrary, is to cut a shallow groove, B (Fig. 1), along the parts that come in contact. In this groove lay rubber tubing, which may or may not be sealed at either end. When the parts are drawn together by means of long screws (brass by preference) the rubber will come in contact so tightly that leakage will be impossible. The wood should be thoroughly shellacked before being put together.
The glass must be of the best white plate, free from bubbles and imperfections. The thickness of it depends on the size of the aquarium ; one twenty-six inches in length would require the glass to be quite a quarter of an inch thick. If no plate-glass is obtainable, a mirror can be cleaned, and, if a good one, will be found to answer perfectly.
The method of fastening in the glass is shown in this diagram. The rubber tube is laid in the groove and the glass pressed tightly against it by a batten of strong wood such as oak; this, when screwed in place, will hold the glass. The batten should be bevelled, in order to prevent its being reflected in the glass. On the upper side of the glass no batten is needed unless the tank is very large. The batten has the disadvantage of casting a shadow, which shadow usually falls on the fish. Heavy copper wire tightly twisted and attached to two strong screw-eyes will hold the sides together. The wire may be removed and a batten substituted when the aquarium is to be packed. When the tank is made it should be smoothly lined with white oilcloth. This is easily cleaned, and its bright surface reflects the light and therefore prevents heavy black shadows.
It will be noticed that when a fish is placed in the aquarium, after stirring up any accessories that may have been arranged, he immediately retires to the farthermost corner, out of reach of the camera. To prevent this his range must be restricted, and the best way to do this is by placing a sheet of glass in the grooves. The smaller the fish the nearer to the front must this glass fence be put. With large fish it is not safe to restrict their movements too much. It makes them very restless and frequently results in their breaking the glass or killing themselves. The glass partition serves also to prevent the fish disturbing the aquatic vegetation which adds so much to the beauty of the picture. This subject will be more fully dealt with later on. It is not advisable to allow the partition to rest on the bottom, as by so doing it interferes with the circulation of the water. A small block placed inside the grooves at the lower end will prevent this.
An extra bottom board covered with white oil-cloth will be found useful when photographing fish that stay on the bottom. This board should have an arrangement by which it can be tilted so that the end farthest from the glass may be elevated.
Handles at either end of the aquarium are useful, but they should not be used when it is full of water; the strain is too great, and is likely to cause leakage. So much for the aquarium. Now we come to its support, and for this I can recommend nothing more simple or more efficient than a pair of wooden horses, upon which two long thick boards should be placed. The length of these boards must depend on the focal length of the lens that is used. The camera placed on these boards, as shown in the accompanying diagram, may be moved back and forth at will. It is seldom necessary to raise it more than a couple of inches, and this may be done by using one or more thicknesses of board beneath the camera.
I have never found that the camera needed to be secured, its own weight being sufficient to hold it in place. If desired, an arrangement could be easily devised by which it would be secured to its support.
With regard to the lens used in fish photography, the more rapid it is the better will be the results. There is no particular advantage in its having very great focal length. About nine and a half inches for a six and a half by eight and a half lens is sufficient. The type of shutter that will be found most satisfactory is the focal plane ; not the drop-shutter in front of lens, but the kind that is set close to the plate. This gives the maximum illumination with the shortest possible exposure, such as is made necessary by the rapid movement of fish. With fish, such as the salmon family, the bluefish, and the runners, jacks and pompano, only the most rapid shutter can be used with success. Another advantage in having the shutter concealed is that fish frequently splash the water, and lens-shutters, such as the diaphragm pattern, are rendered useless by salt water.
In the list of material required for this work will be found instantaneous isochromatic plates. Under ordinary conditions these plates are perhaps not quite so rapid as the regular plates, but with the greenish or yellowish tinge of the glass and water, and the greens, yellows, and reds of the aquatic vegetation, it will be noticed that most of the colours are those which most easily affect the isochromatic film. Therefore in fish photography they will be found not only as quick as the ordinary extra-rapid plate, but, owing to their sensitiveness to the colours just mentioned, will yield a more perfectly exposed negative, Their value will be most noticeable when the fish to be photographed is strongly coloured, where bright yellow, red, and dark green may be side by side. The ordinary plate would show only a slight difference of tone between the yellow and red, and perhaps none at all between the red and green, while the instantaneous isochromatic would show a decided difference in the three colours. Not giving the red its full value, of course, because that can only be obtained by using the slow isochromatic or by the addition of a ray-filter. It is a rare thing, however, to find a fish that will remain quiet enough to allow of these being used.