贺摄影板块的建立，献上一篇1917年出版的有关金鱼摄影的文章。英文不算复杂，就不做翻译了。
PHOTOGRAPHING FISHES
Achievements of modern photography havedone much to lessen the difficulties of photographing living fish, although apicture good in every respect demands all the patience and care at one'sdisposal. Exact photographic records areextremely interesting to the fancier, valuable to the scientist and form theonly certain basis for noting the changes in the fancy breeds of goldfish.
A high-grade lens that will work at F 6 orbetter and a shutter that will give an exposure of 1-25 second should beused. Sufficient length of bellows isneeded so that the fish may be photographed about two-thirds life size. Sharpnegatives can be had in this way and those which turn out well can beenlarged. Direct photography at lifesize is not practicable, as the depth of focus and power of the light are verymuch cut down at this close range. The chances of blurring by movement are greatlyincreased by attempting to photograph at life size. A photographic plate size 5 x 7 is quitesatisfactory for photographing goldfish.
For the most of the tropicals, 4 x 5 issufficient. The Graflex camera is veryconvenient, allowing one to focus up to the instant of exposure.
To properly carry out this work a specialphotographing aquarium should be prepared. It should be seven inches deep, seven inches wide and two and one-halfinches through from front to back. Thefront should be of /-inch plate glass. This is important. A white background forphotographing dark subjects and a black for light ones will be needed. A pieceof cardboard folded twice and stood on end immediately in back of the aquariumwill be found to be satisfactory. The back may
be painted with flat black to serve for thealternate background. If this is done the two creases should be stripped withtape so the board will not separate when the fold is reversed. To carry out thebackground effect completely, cut a piece of glass the size of the insidebottom of the aquarium. Paint one sidewhite and the other black, using either as required. The fish will frequently sink to the bottom,and if the back-ground is of the proper color throughout, the photograph can beas well made there as higher in the water.
A very important item is to have a movableglass partition so that the fish may be forced near the front glass and thuskept in focus. Thin brass forms to snap on either top end of the aquarium andleaving notches filed to hold glass partition in position will be found most convenient.
This aquarium was used in making all thephotographic reproductions of fishes shown in this volume. Note glass partitionfor keeping subject in focus.
All the camera except lens should becovered with a black cloth at time of exposure to prevent its own reflection inthe aquarium. The author believes thatsunlight furnishes the best illumination, giving better color values andmodelling than flashlight. Exposuresshould be made only on very bright days from eleven until two o'clock, and inthe period,if possible, between April 10 and September 1. At other times flash-powder will be better,using a liberal supply. Care should betaken not to allow the dust from flashlight to settle in the aquariums as itcontains metallic salts injurious to fishes. Keep the sun on the subject anddirectly behind the camera. The watershould be as free as possible of all particles, as they show in the picturewith annoying distinctness. Much patienceis sometimes required to get a fish into a satisfactory "pose," but whena good picture is obtained, it is well worth all the trouble it costs.
The photographing aquarium shown herewithwas constructed by pouring cement in a form surrounding the four uprights. Justafter the cement is poured, quarter-inch square sticks of wood should bepressed in where the glass is to stand. These are removed when cement is dry.
Waterproof the base as described on page216, then fill all four depressions and posts with aquarium cement and insertglass. Owing to small size of aquariumit is best to do all cementing before any glass is inserted for it isimpossible to satisfactorily reach inside. Only the front needs to be of plateglass. This should be inserted first and all surplus cement neatly clearedaway. It will be noted that this style of construction has no bottom metalframe to interfere with photographing when the subject happens to be low, whichis often the case. One part of cement totwo of sand is a good proportion. Whitecement makes a pretty effect and when using a white background, no other insidereflector is needed. This aquarium was used in making the photographicillustrations of fishes in this volume.
Unless the base immediately in front of theglass is of a dull black it will be desirable to cover it with a dull black orred cloth. Black is better.
