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544 THE PHOTOGRAPHIC NEWS. [November 13, 1868. above is dissolved by means of considerable agita- The ... 15 parts. Powdered sandrac ... Camphor, broken up small Venetian turpentine Oil of lavender 2} parts 2 part i " irritated with stray light which penetrates through the transparent portions of the clothing, &c. Besides, by this means the varnish is protected from friction, a matter of some importance if the coating is still fresh. It has often been proposed to gum the negative after being fixed, then to retouch it, and finally to cover it with varnish. This method of operating gives, it is true, in skilful hands, very excellent results ; but it often happens that in varnishing, the varnish only partially penetrates the thin film of gum, thus rendering the negative frequently useless from the spotted character of its surface. Beyond this it is necessary that especial care should be exercised in the touching up of a gummed negative, as the point of a pencil easily pene trates the film, and thus causes the formation of holes: for these reasons, therefore, it is much more desirable to do the retouching upon a varnished film. Negative varnish which contains an appreciable quan tity ot shellac does not always bear manipulation with a pencil, which, in this description of work, plays a very im portant role; I would recommend, therefore, the employ ment of a varnish the composition of which I give below for the purpose ; it will be found to answer admirably, and may likewise be used with advantage upon positive pictures. My formula is as follows :— tion in Absolute alcohol much, or more, to the chance of a print being permanent than to its cost of production. After the prints have been toned, we pass them through two changes of water, and they are then put into the hypo solution, which is made up of a strength of 5 ounces of hypo to a pint of water. The prints are immersed in this solu tion one by one, each one being turned over two or three times to ensure the absence of air-bubbles; this done, they are kept moving by rocking the dish, and occasionally by turning them over in it for fifteen minutes. They are then taken out one by one, drained, and plunged for about five minutes more in afresh solution of hypo, the same strength as before. This second solution is used again the next day as the first fixing bath. By this process of double fixing I believe the prints are rendered more permanent than if they had only one bath of hypo. I am looking out constantly for the supply of hyposulphite of ammonia which has been promised so long, and as soon as that comes I hope to have some more experiments on fixing to report. After fixing, the prints are thoroughly washed in a dish by repeated changes of water, and are then consigned to the “ washing machine ” for the night. I have, already described our apparatus for washing in these pages, and therefore need not again refer to it. The prints in the morning are removed to a dish of clean water, and brushed over, back and front, with a large camel-hair flat brush, to remove any little impurities which may have come upon them in the washing trough. They are then set in a heap on a sheet of glass, and sent up to be dried, first between blotting- paper, and then by being spread out on a table. Starch is used for mounting, and when waxing is required, the formula which we first tried—and which was published in the News in a leading article shortly after M. Adam-Salomon’s visit to England—is preferred to any other. Indeed, I cannot get any other used at all, as our own is so much preferred. When used, the varnish is diluted, according to circum stances, with a more or less quantity of alcohol which has been previously mixed with water in the proportion of 10 or 12 parts of alcohol to 1 of water. The older the varnish on the negative becomes the harder it gets, and the quality of the pencil is regulated by the state of the varnish upon the plate, a hard pencil being re quired for a hard varnish, and vice versa. The first thing to be done is to work up and equalize any unevenness upon the face of the portrait, as, for instance, summer freckles and other dark spots; these are manipulated with the pencil until they are not to be distinguished from the surrounding parts of the negative; and in like manner the large shadows may be worked up, and particularly the abrupt glaring gradations sometimes seen upon negatives ; strongly marked folds and other similar parts must also be softened down, in order to render the whole picture more harmonious. Elaboration with the pencil is, however, not always successful, for in very transparent portions the lead is not sufficiently opaque, as, for instance, under the eyes, &c. In these instances a black crayon or so-called Creta polycolor, may be used with much advantage, being employed in the same manner as a pencil ; better results still are obtained with ordinary black lithographic chalks, and, as the latter are generally very soft and the particles easily disintegrated, they impart more opacity than black lead, and answer the purpose admirably. When these means are unavailing, a circumstance which sometimes happens when the pictures print too deeply and contain shadows of too dark and heavy a character, other methods of improvement must be tried. Ordinary black indian ink mixed with gum arabic, and used of the con sistence of a syrup, may be applied with advantage. It is well to add a little glycerine to the gum in the proportion, perhaps, of two to four drops of the former for every ounce of gum solution; it then becomes easier to manipulate, and when dry is not so brittle upon the varnish, and not so liable, therefore, to peel off from the film. By using larger or smaller additions of gum, the opacity of the colouring matter may be regulated with the greatest nicety ; and in parts where one coating is insufficient to render the plate of the requisite density, a second or often repeated application RETOUCHING THE NEGATIVE. BY JOHANNES GEASSHOFF.* Thebe are many methods extant for retouching negatives. I myself have essayed several, but shall confine myself in the following remarks to the mode of operating which in my opinion is the best and simplest, and which I have for a considerable time made use of; excellent results may be obtained with it after suitable practice, but, as a matter of course, perfection can only be secured by a sufficient amount of skill and experience. To facilitate the manipulation of the negative it is as well to provide oneself with a retouching frame, to be had of any dealer in photographic apparatus. The frame is placed at the window, the negative is screwed into it in a slanting position, and the looking glass so arranged as to reflect the light upon the image ;by this arrangement the negative is clearly and distinctly seen without incon venience. At the same time the operator must be careful to seat himself with the frame in a dark locality, and not, therefore, in the glass room; if it is necessary to work in the evening, the mirror in the frame cannot be used for reflecting the light from the lamp, and it is best to have recourse to a light placed upon a low stand furnished with a globe of ground glass, so that the negative may be lighted up with diffused illumination. The most difficult negatives to operate upon are generally those of large portraits, and it is the face of these in parti cular which especially needs attention. To render the task easier, several pieces of stout opaque paper of the same size as the negative should be provided, all of them having round or oval openings of different sizes cut into them; with these the portrait is covered, with the exception of the head (which should be visible through the opening), and thus one’s sight and attention are concentrated upon that portion of the plate to be operated upon, and one is not * Extracted from Grasshof"‘s Manual on the “ Retouching of Photographs.”
