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October 16, 1891.] THE PHOTOGRAPHIC NEWS. 723 on the negative with an aureola, or halo, due solely to the reflecting action of the glass employed as a support, and which has nothing in common with what is called the veil, any more than it has with another accident that occurs with a still further prolonged exposure, and which consists in the reversal of the image, positive objects appearing upon the negative. It is, therefore, useless (and I repeat it earnestly, on account of the contrary belief of so many professionals) to make night in order to photograph night, and to believe that one is obliged, for example, to represent a drawing room without chandelier and a dinner without candles. To return to what occupies us, leaving all undisturbedly lighted, let us be anxious only lest our background shall receive at second hand too great a number of magnesium rays diffused through the part of the room where we can not entirely prevent the reflection of the flash from pene trating. For that, the utilisation of the leaf of the door, open on the side of the sitter opposite the flash, will have the double advantage of arresting, on the passage, the greater portion of the rays that tend to enter the dark room, and of sending them back to the side of the sitter, who, without that, would run the risk of being too deeply shaded. It is possible, even, by placing the sitter and light geometrically in a right line with the edges of the jamb and the open leaf, to prevent any direct ray from entering the room. After this the darkness of it will be certainly comparable to that employed by Mr. Marey for his remarkable photo-chronographic studies on locomotion, that is to say, the most perfect that has been realised up to the present. Since now, without trouble and expense, we are here possessors of an ideal background, nothing remains but to utilise it in order to derive from it all that it is capable of giving us. To commence, would you like to try one of those simple, degraded blacks which so well bring out light clothing? It will suffice, after making the exposure as indicated above, to operate according to the classic method by putting into the camera a shutter containing an aperture which allows of the passage of only that part of the image that it is desired shall reach the plate. Does the operation seem to be somewhat delicate, and does the regulation seem tedious by the light of the candles? Or does the apparatus refuse to allow of the introduction of the shutter? This is how it always will be possible and easy to operate. Take some sort of a dark fabric, and, throwing it over the back of two chairs a slight distance apart in front of the sitter, regulate the curvature of the falling fold in such a way as to conceal the sitter up to the shoulders from your eye, placed against the objec tive. Then flash the light in front of this screen in such a way that the face seen from the apparatus, receiving no direct ray, shall remain black for the objective. There will be thus obtained upon the plate a bust entirely detached from a dark ground and degraded toward the bottom, where the edge of the veil will have become so much the lighter and softer in proportion, as it will have been less perfectly in focus, that is to say, nearer the apparatus. There is no need of adding that, on reversing the process —that is to say, on substituting white for black, light for shadow, and a sheet (or better, on account of the folds, indented cardboard) for the drapery—it is possible to obtain directly upon the negative the ordinary degraded white that it takes so much trouble to obtain in printing photograph by photograph. So it is to be wagered that, having got a liking for it through an easy success, you would not wish to stop there, but would feel inclined to apply the method to the realisation of some of those tempt ing trifles to which attention has so many times been called in this journal. Who has not, after making a negative, been con fronted by the too sensible difference between the blacks of the profiling and the accessory draperies? Now, by the use of our background, the risk would be much lessened ; but to succeed almost to a certainty one has only to proceed as follows. A first exposure on a shadow ground is made with the pedestal, the position of which must be accurately marked on the ground glass. Then a second exposure of the model in half-length degraded upon black, so regulated that the soft lights of the bust on the ground glass are lost over the pedestal—an opera tion that is reduced to a simple control if advantage is taken of the fact that, this time, there is nothing to prevent the pedestal from being left in place in front of the model, since it must, in definitive, be hidden by the veil. Upon the negative we will find the image of the pedestal separated from the bust by a degraded zone, a few lines of which, through a broad after-touch, it will suffice to arrest and make more marked, in order to obtain a result which will not only have suppressed the faults of the profile, but also and especially its stiffness, &c., in the cut-out parts of the living bust. Remark that it would have been perfectly allowable for us at the first exposure (that of the pedestal) to take at the same time, around the pedestal, any group whatever of persons or objects fillingall the parts of the black field that it was not necessary to reserve for the bust itself. And then, instead of the effect of a solitary and somewhat conventional bust, the trick of which is easily defined, we obtain family pictures which are very puzzling through the presence, in a second edition, of the person all entire from head to foot, a part of whose form attracts in the first place one’s whole attention. The system of double exposures thus understood, may, moreover, with a little additional complication, lead us to applications in other ways, original without being much more difficult, by combining changes of distance of the apparatus between each of the operations.—Eng. Mechanic. Posinve Prints on Paper.— Dissolve in water 1,000 grammes, peroxalate of iron and ammonia 300 grammes. This solution being prepared, keep it in obscurity, as it is rapidly decomposed by light. Choose a paper sized with gelatine, use the smoothest side, and make a mark on the back with a pencil. Pour the above solution into a porcelain dish, float your paper on the solution for four minutes, and hang up to dry in obscurity. The solution may be used until exhausted, and the paper coated with this salt kept indefinitely, provided they are both kept away from the light. The exposure in the positive frame is made according to the intensity of the light or of the print; if on coming from the frame the print appears a little weak, or in the condition of a negative, care must be taken to have at once recourse to the following operation :— The print is floated on a five per cent, bath of nitrate of silver. For the sake of economy, the print may also be placed on bibulous paper, and the surface rapidly passed over with a cotton brush (a wad of cotton in a tube). The image imme diately appears of a purplish-brown colour if the exposure has been good. If the paper is sized with starch or arrowroot the tone of the image will be blacker. The print may be toned with chloride of gold. It is fixed either with hyposulphite of soda, or in the following bath :— Sulphocyanide of potassium, 100 grammes ; water, 1,000 grammes. Wash in several waters. — Chas.Gravier in L’Amateur Photographc.
