INSTANTANEOUS PHOTOGRAPHY.
The photographing of objects which, being in more or less rapid motion, required that the exposure should be very brief, so that the motion might not produce notice able blurring, was, previous to the advent of dry plates, a very difficult matter, and one in which only occasional success was met with, even when the conditions were most favourable. Everything had, so to speak, to be strained. The light required to be at its very best, the lens required to be one more rapid than would give the best of results as regards depth of focus, etc., and the chemicals had to be used in certain conditions which made the working of them even more troublesome than usual. It may be conceived what an alteration was brought about when plates were invented which re quired but a tenth or twentieth of the amount of light action to impress the image. Immediately all straining ceased, and conditions very slightly different from those required for ordinary landscape photography were found to be adapted to instantaneous work.
The subjects which are adapted for instantaneous treatment are innumerable. We may mention a few. First we may place sea-views, either sea and sky alone, which often make a beautiful picture, or the sea with all the various forms of vessels which float on its surface. Yachts, steamers, pleasure-boats, and such like may be depicted and may be made to afford beautiful pictures.
River scenes may be rendered as well as seascapes. Crowds of people in the street may be portrayed, and afford marvellous studies of life as it is in our crowded cities. Horse-races, foot-races—subjects without end— may be thought of ; thus not merely dead life, but living things and motion are portrayed.
These are the subjects which make pictures. There are others which may be treated that do not give in themselves results that can be considered as artistic ; yet they are highly interesting and instructive from a scientific point of view. More has been learned in the last few years of the positions which the limbs of animals take in rapid motion than had been learned through all the time which had gone before, and this is solely on account of the use which has been made of instantaneous photography.
The only condition necessary in any of the subjects which we have mentioned is that it should be brightly lighted, and that it should not be of such a nature as to consist in great part of heavy shadow.
The only apparatus necessary, in addition to that used for ordinary landscape work, is a lens of the " rapid " landscape type (which may constitute one of the several which most photographers use for ordinary view-taking) and an instantaneous shutter.
A rapid lens we have mentioned as a necessity, al though, in fact, it can scarcely be said to be so. It is a most useful piece of apparatus to be in the possession of photographers who take up instantaneous work, because it enables them to work on subjects and under conditions which would otherwise be impossible. We have seen a very fair picture of a train in motion taken with the camera of the Students' Set and the single achromatic lens which accompanies it.
There are certain subjects which can almost always be taken without the use of a rapid lens, or an instant aneous shutter either, and these are the ones on which the beginner at instantaneous work should make his first essay. They consist of sea and sky without ship ping, or with such only in the distance, and of river scenes in which it is desired to secure the ripple of the water but not boats in motion.
'Whilst mentioning sky, we should point out that one of the chief charms of instantaneous work is that almost always it is possible to secure not only the land or sea scape alone, but at the same time any clouds which there may be along with it. The subjects being such as have no very deep shadow require comparatively short ex posures, and as a consequence the sky is not greatly over-exposed.