The photographic news

• Bandzählung: 13.1869
• Erscheinungsdatum: 1869
• Sprache: Englisch
• Signatur: F 135
• Vorlage: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: Hochschule für Grafik und Buchkunst Leipzig
• Digitalisat: SLUB Dresden
• Rechtehinweis: Public Domain Mark 1.0
• URN: urn:nbn:de:bsz:14-db-id1780948042-186900000
• PURL: http://digital.slub-dresden.de/id1780948042-18690000
• OAI: oai:de:slub-dresden:db:id-1780948042-18690000
• Sammlungen: LDP: Historische Bestände der Hochschule für Grafik und Buchkunst Leipzig
• Sammlungen: Fotografie
• Bemerkung: Heft 545 (S. 73-84), Heft 547 (S. 97-108), Heft 589 (S. 599-610) fehlen in der Vorlage. Paginierfehler: Auf Seite 444 folgt Seite 443
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• Digitalisat: SLUB Dresden
• Strukturtyp: Ausgabe

16 THE PHOTOGRAPHIC NEWS. [January 8, 1869. it would not be fair to say that this process has been tried and found wanting, because it scarcely seems to have been tried. I understood that the patent does not describe the process fully enough to enable any one to work it; that Mr. Bouncy keeps back some secret, in which case, I suppose, the patent is of no use. I have seen some assertion of the tendency of bitumen to crack, and so render the printing-ink photographs unstable. Is this so ? I must confess, beyond the talc picture chipping away (not a good sign of perma nency), I have no evidence of what may bo expected. I saw a para graph lately in a daily paper saying that these pictures would bear soaking for about a week, or boiling or baking for six hours. I did not see the advantage of this power to stand fire and water, inas much as I never heard of anyone who wanted to bake or boil photo graphs. Nevertheless, when I saw the paragraph, it occurred to me that I should like to apply a similar test to silver prints. I accord ingly took a couple of card pictures and placed them in the kitchen oven at the heat usually employed for baking, and another couple, and placed them in the kitchen boiler, and I devoted an extra copy I had of the Woodbury print of the ‘ Killarney Girl,’ and placed one-half in the oven, and the other in the boiler, and left them all for six hours. At the end of that time they were withdrawn. The boiled silver prints were scarcely altered at all; but, if anything, they were a shade browner, and a shads lighter, in the Woodbury print the image had disappeared altogether in boiling, leaving a piece of white paper. All the baked prints were quite unchanged. So much for the severity of the tests. I do not think anything the worse of Woodbury’s prints because, being formed of gelatine rendered in soluble, it would not stand prolonged boiling, any more than I should think worse of a Pouncy print that it would not stand prolonged im mersion in benzole. “ I have confined my remarks purely to the question of permanency, without entering on that of beauty. I might say, however, that none of the carbon processes surpass silver in beauty. Woodbury prints generally have a curious glazed effect, and with sunken whites and raised blacks, which is inartistic. I think that they would suit decorative work better than work of fine art proper. All Pouncy’s prints I have seen have a vulgar varnish over them, which to me is intolerable. Swan’s prints are, out of all proportion, the finest of the carbon pictures, and, on the score of beauty, nothing can be said against them. Some, with a dead instead of a glazed texture, are very beautiful. “ To conclude my long letter, which will, I am afraid, weary you— and, if you publish it, your readers—my position is, that silver prints, if properly printed, toned, fixed, and washed, are permanent, and fail only when some point is neglected; that the best that can be ex pected of carbon prints is permanency when every point of care is used in the operations, and they will fail like silver prints if these points are neglected. What, then, have we to gain by giving up silver and adopting carbon ?—Very truly yours, Theta.” We will offer one or two brief comments on our correspon dent’s observations, and, as shortly as we can, answer bis questions. We believe, and we have often repeated, that with proper care in producing and preserving silver prints they will have a very long tenure of permanency. It must not be forgotten, however, that, at best, an image formed of a finely-divided deposit of metal like silver, so subject to change from atmospheric causes, is less likely to be stable than one formed of a substance so durable as carbon. The cause of failure, too, in the carbon print to which he adverts is due to the gelatine with which the transfer is effected not having been made insoluble. The failure was not inherent in the process, but the result of a neglect on the part of the pro ducer, and its possibility has been anticipated and provided for from the first. We may here, without being egotistical, quote a brief passage from our own work on Pigment Print ing, written upwards of two years ago :— The only possible source of deterioration in the prints produced by the method we have described exists in the thin coating of gelatine with which the print is fixed to its final support. By means of mois ture and friction the print might be removed; this, it is true, is destruction, not fading or instability in the usual sense. But it is, happily, possible to remove even this susceptibility to injury. ***** One of the means used by Mr. Swan to render the gelatine insoluble is quite novel, and constitutes one of the first applications of his discovery of the property possessed by salts of the sesquioxide of chromium of rendering gelatine insoluble. A solution of common alum has, to a certain extent, the power of waterproofing the prints, and general fixture with alum is quite sufficient. Where, however, more thorough waterproofing is demanded, the prints, after transfer, should be treated with a one per cent, solution of chrome alum. Mr. Swan has shown us some prints very successfully transferred without a press. The transfer was effected with the gelatine solution ordinarily used, to which had been added one-twentieth of a ten per cent, solution of chrome alum. Prints intended for colouring in water colour should be chrome-fixed. For prints which have to be treated with water colours, or submitted to moisture—or, indeed, for all prints—a method is provided of rendering them waterproof. Nevertheless, we submit that as prints are not usually kept in water, the capacity for remaining uninjured after soaking therein is not a necessary condition of permanency in a gelatino-car- bon print, any more than it would be in a water colour drawing, or than, as our correspondent suggests, the capa bility of resisting prolonged soaking in benzole is a neces sary condition of a photograph in printing-ink, or of an engraving, or an oil painting. We know nothing of the conditions of the trial referred to by our correspondent; but it is clear that to give such a trial any value it should not be made on chance prints, which may have been imperfectly or carelessly manipulated, but on such prints as the origin ator of each process should provide as fair examples, upon which he was willing to stake the reputation of the process. It may be replied, that such a plan would give opportunity for preparing prints with extra care. Precisely so: and when a process is being tested, such care is not only admis sible, but imperative; otherwise a decision might be obtained implying faults in a process, which faults merely belonged to the carelessness of the person who worked the process. The same answer applies to the Woodbury print: a pro cess had been neglected, and the image remained soluble. It is much to be regretted that during the experimental days of both these processes examples got into circulation in which the final process of rendering insoluble had been neglected, subjecting them to much misjudgment. Into the question of the business delays in working the Woodbury process we cannot enter. They have been very unfortunate, and to no one more than the inventor ; but it would bo un fair, we think, to draw inferences prejudicial to the process 4 from sneh facts. Neither can we enter into the question of the business arrangements of the Autotype Company : wo believe that they are actively and successfully prosecuting their business, and that they have announced their readiness to grant licenses; to what extent such licenses have been taken, or to what extent the process is worked, we cannot at present say; but we believe that many licences have been taken, and, judging from the number of carbon prints in circulation, the process is clearly very extensively worked somewhere. Any absolutely new process, no matter how perfect, must necessarily require a long time to supplant a process so simple, so effective, and so well established as silver printing. In regard to Pouncy’s process we can give no information that we have not already published. With the exception of the examples exhibited last year in Paris, and subsequently in the Crystal Palace, we have not seen any of the prints for a long time. When we first described the process we saw valuable capabilities in it, and we have in nowise changed our opinion. Whether the specification fully describes the process, or whether some essential point is kept back, we do not know. If so, of course the patent would be invalid. We have never prepared tissue by it, but, using Mr. Pouncy’s tissue, we have got very good results. Some progress has, we understand, been made in the process, but, as our correspondent remarks, neither information not specimens have come much under the attention of the photo graphic world. We do not attach the slightest importance to the cracking properties of bitumen, in the small propor tion in which it is present in carbon prints produced by it, nor doubt their permanency, any more than we fear the permanency of others owing to the alleged perishable nature of gelatine. The latter, when properly treated in carbon prints, is practically converted into leather. We believe that all carbon prints properly produced will be absolutely permanent. Whilst we have always felt a deep interest in all carbon processes, we take no issue with our correspondent on the score of silver printing. Skilfully conducted, it gives very beautiful results, and, if proper care be used in preservation, as well as production of the prints, whilst they may lose