PHOTOGRAPHIC CORRESPONDENCE.
Mounting Positives.—If the print and the mounting paper, or Bristol board, are both made equally damp, and the back of the picture covered with thin paste, they adhere without any unevenness; and if the print is on the fine Canson's paper, the appearance is that of an India proof. They should remain until perfectly dry in a press.
H. W. Diamond.
Mounting of Photographs, and Difficulties in the Wax-paper Process.—May I request a little additional information from your correspondent Seleucus, Vol. ix., p. 310., respecting the mounting of photographs? Does he mean merely the painting the edges, or the smearing of the photograph all over its back with the Indian-rubber glue, prior to sticking the proof on the cardboard? If the former, which I apprehend he does, Seleucus will necessarily have the unsightly appearance of the picture's buckling up in the middle on the board being bent forward and backward in different directions? May I take the liberty of asking him in what respect the plan proposed is superior to that of painting over the edges with mucilage of gum arabic, containing a little brown sugar to prevent its cracking, allowing it to dry, and prior to the placing it on the card, slightly moistening it; a plan superior to that of putting it on the board at first, as all risk of a portion of the gum oozing out at the edges is thereby avoided.
I have long been in the habit of mounting prints and photographs in a way which prevents their buckling, keeps the paper underneath quite smooth, and in other respects is so perfect, that it positively defies the distinguishing of the picture from the paper on which it is mounted. I am not certain that my plan is applicable to the mounting on card-board, as it cannot be wetted and stretched, thinking it useless to make use of such a costly material when a tolerably thick drawing-paper will more than serve the same purpose at a very considerably less expense, seeing that the photograph thus mounted bears a much closer resemblance
to that of a good and costly print. A good plain or tinted sheet of drawing-paper, 30 inches by 22, may be obtained at the artists' colour shops for sixpence, sufficiently large for two drawings, 9 inches by 11, allowing a sufficient margin.
After various trials, the plan I have found decidedly the best is the following:—Soak the drawing-paper in a vessel of water for ten minutes, or until it appears by its flaccidity to have become perfectly saturated; put it at once into an artist's stretching frame, brush over the back of the photograph with rather thin and perfectly smooth paste, allow it a few minutes to imbibe a portion of the moisture of the paste, and then lay it smoothly down on the damp paper now on the stretching frame, of course carefully pressing out all air bubbles as you gradually, beginning at one side, smooth down the pasted picture. It should remain in a dry place (not placed before a fire) until the whole has become quite dry, about ten or twelve hours. It may then be taken out of the frame, cut to the desired shape, and a single or double line nicely drawn around the picture, at a distance suitable to each individual's taste, by the help of sepia-coloured ink and a crowquill pen, both of which may also be bought at the artists' colour shop. Should it be required to be still more nicely mounted, and to appear to have been one and the same paper originally, the back edges of the picture should, previous to laying on the paste, be rubbed down to a fine and knife-like edge with a piece of the finest sand-paper placed on a wine cork, or substance of a similar size. The drawing-paper should be of the same shade and tint as the ground of the photograph.
A novice in the wax-paper process (having heretofore worked the collodion and calotype, from its very desirable property of keeping long good after being excited, i. e. the wax paper), I am very desirous of getting over an unexpected difficulty in its manipulation; and if some one of the many liberal-minded contributors to your justly wide-spread periodical, well versed in that department of the art, would lend me a helping hand in my present difficulty, I should feel more than obliged for the kindness thereby conferred.
My wax-paper negative, much to my disappointment, occasionally exhibits, more or less, a speckled appearance by transmitted light, which frequently, in deep painting, impresses the positive with an unsightly spotted character, somewhat similar to that of a bad lithograph taken from a worn-out stone. I should wish my wax-paper negative to be similar in appearance to that of a good calotype one, or to show by transmitted light, as my vexatious specimen does when viewed on its right side by reflected light. As the most lucid description must fall far short of a sight of the article itself, I purpose enclosing you a specimen of my failure, a portion of one of the negatives in question. Would immersion, instead of floating on the gallo-nitrate solution, remedy the evil? Or should the impressed sheet be entirely immersed in the developing fluid in place of being floated? And if in the affirmative, of what strength should it be? I have thus far tried both plans in vain.
Henry H. Hele.
[The defects described by our correspondent are so frequent with manipulators in the wax-paper process, and which Dr. Mansell has called so aptly a "gravelly appearance," that we shall be glad to receive communications from those of our numerous correspondents who are so fortunate as to avoid it.]
The New Waxed-paper, or Céroléine Process.—The following process, communicated to the French paper Cosmos by M. Stephane Geoffroy, and copied into La Lumière, appears to possess many of the advantages of the wax-paper, while it gets rid of those blemishes of which so many complain. I have therefore thought it deserving the attention of English photographers, and so send a translation of it to '"N. & Q." As I have preserved the French measures—the litre and the gramme—I may remind those who think proper to repeat M. Geoffroy's experiments, that the former is equal to about 2 pints and 2 ounces of our measure; and that the gramme is equal to 15.438 grains, nearly 15½.
Anon.
I send you a complete description of a method for either wet or dry paper, which has many advantages over that of Mr. Le Gray.
I assure you it is excellent; and its results are always produced in a manner so easy, so simple, and so certain, that I think I am doing great service to photographers in publishing it.
1st. I introduce 500 grammes of yellow or white wax into 1 litre of spirits of wine, of the strength usually sold, in a glass retort. I boil the alcohol till the wax is completely dissolved (first taking care to place at the end of my retort an apparatus, by means of which I can collect all the produce of the distillation). I pour into a measure the mixture which remains in the retort while liquid; while it is getting cool, the myricine and the cerine harden or solidify, and the céroléine remains alone in solution in the alcohol. I separate this liquid by straining it through fine linen; and by a last operation, I filter it through a paper in a glass funnel, after having mixed with it the alcohol resulting the distillation. I keep in reserve this liquor in a stopper-bottle, and make use of it as I want it, after having mixed it in the following manner.
2nd. Next I dissolve, in 150 grammes of alcohol, of 36 degrees of strength, 20 grammes of iodide of ammonium (or, of potassium), 1 gramme of bromide of ammonium or potassium, 1 gramme of fluoride of potassium or ammonium.
I then pour, drop by drop, upon about 1 gramme of fresh-made iodide of silver a concentrated solution of cyanide of potassium, only just sufficient to dissolve it.
I add this dissolved iodide of silver to the preceding mixture, and shake it up: there remains, as a sediment at the bottom of the bottle, a considerable thickness of all the above salts, which serve to saturate the alcohol by which I replace successively the saturated which I have extracted by degrees in the proportions below.
3rd. Having these two bottles ready, when I wish to prepare negatives, I take about 200 grammes of the solution No. 1. of céroléine and alcohol, with which I mix 20 grammes of the solution No. 2.; I filter the mixture with care, to avoid the crystals which are not dissolved, which always soil the paper; and in a porcelain tray I make a bath, into which I lay to soak for
about a quarter of an hour the papers selected and cut, five or six at a time, till the liquor is exhausted. Taken out, hung up by the corner, and dried, these papers, which have taken a uniform rosy tint, are shut up free from dust, and kept dry. With regard to the sensitizing by nitrate of silver, the bringing out of the image under the action of gallic acid, and fixing the proof by hyposulphite of soda, I follow the usual methods, most frequently that of Mr. Le Gray.
I add only, if I have any dissolved, 1 or 2 grammes of camphorated spirits to 1 litre of the solution of gallic acid.
Allow me, Sir, to say a few words on the great advantages I have always remarked in preparing my negatives by this method.
All those who use papers waxed by Mr. Le Gray's process, know how many, how tedious, and how difficult are the operations before the sensitizing by nitrate of silver. They know too how much care is necessary to obtain papers uniformly prepared and without spots, in the midst of such long operations, in which there are so many opportunities for accidents. In fact, one must be always upon one's guard against the impurities of the wax obtained from the shop; against the dust during the impregnation of the paper; and, while using the iron, against the over-heating of the latter, and against the bad quality of the paper used to blot.
Photographers know also how much wax they lose by this process, and how much it costs for the quantities of paper necessary to dry it properly. They know likewise how difficult and tedious it is to soak a waxed paper which has been previously in a watery solution. On the contrary, by the method I have described, the iodizing and the waxing is done by one single, simple, and rapid process; the saturation is, as may be conceived, very uniform, and very complete, thanks to the power of penetration possessed by the alcohol; and that marbled appearance of the ordinary waxed proofs, which is so annoying, cannot be produced by this method, thanks to the character of the céroléine: this body is, in fact, of a remarkable elasticity.
The solution of céroléine in the alcohol is more easy to prepare, and comparatively costs little; and the remains of stearine and of myricine can either be sold again, or, in any case, may be used to wax fixed proofs.
The solution of which I have given you the formula, is photogenic to a very high degree; in fact, used with papers, either thin or stout, it gives, after the first bath of gallic acid, blacks of an intensity truly remarkable; which it is impossible to obtain to the same degree with Le Gray's paper, and which other papers scarcely take after having been done a second time with the acetic acid, or the bichloride of mercury. At the same time, it preserves the lights and the half-tones in a way that surprises me upon each new trial (I have not yet been able to obtain one clear proof by gallic acid, with the addition of nitrate of silver). The transparency of the proofs is always admirable, and the clearness of the object yields in nothing to that of the proofs obtained by albumen.
The paper, prepared in the manner I have described, is also very quick as compared with Le Gray's paper—at least one fourth quicker; and preserves its perfect sensitiveness in the same proportion of time, three days in twelve. Thus, it is at the same time quicker and less variable. This comparative rapidity may be very well understood, by remembering that the céroléine is an element much softer than its compound; and possesses a photogenic aptness which is peculiar to itself, which science will, no doubt, soon explain.
To succeed in the preparation of the céroléine, it is important to work with wax of the best quality; this is not easy in Paris, where they sell, under the name of wax, a resinous matter which is only wax in appearance. It will be well to observe, with the greatest care, the smell and the look of a fresh cut.
[This article reached us after our preceding note was in type. We shall be glad to hear from any correspondents who have tried this process how far they find it to be one deserving of attention.]