The Dictionary Of Photography

A True Historic Record Of The Art & Practice Of Photography 100 Years Ago.

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Carbon Processes
water by throwing the hot water on to it with the hand, or by means of a cup or soft broad brush, or a small sponge. As this is done it will be found that the gelatine unacted upon by light will be dissolved away and will carry with it the colouring pigment, leaving the print in all its beauty. As soon as de-velopment is complete it is plunged into a bath of cold water to set the gelatine, and then it is placed in a bath of the following: -
Powdered alum ... ... ... ... I oz.
Water           ... ... ... ... ... 20 ozs.
This not only fixes the print by hardening the gelatine, but it also discharges the yellow colour of any remaining bichromate salt. It is allowed to remain in this bath for about ten minutes, or till the colour is entirely discharged from the whites of the picture, and finally rinsed twice or three times in clear water. The print is now ready for transferring to its final support, of whatever nature that may be; but before this transfer can take place it is necessary that the final support should be prepared to receive it, for which purpose it is coated with the following : -
Nelson's gelatine ... ...... ... 1 oz.
Water           ...... ... ... ... 20 ozs.
Soak the gelatine in the water for an hour, or till soft, and then dissolve by the aid of a gentle heat. When dissolved, add to it gradually 12 grs. of chrome alum dissolved in 1 oz. of water. The commercial final support, which is a stout paper, is already prepared, and merely requires soaking in alum solu-tion, ^ oz. to the pint, an hour before using. The print on its temporary support and the final support, whether freshly prepared or not, are brought into close contact under the surface of wrater, and complete contact obtained by means of a squeegee, and are then placed in blotting boards, or hung up till perfectly dry, when the temporary support can be stripped off, leaving the print in its proper position. It is advisable for any amateur who may wish to work in carbon to obtain Sawyer's "ABC Guide to Autotype Printing." The disadvantage of this form of the process is the necessity for the use of reversed or film negatives, or of a temporary support; but the non-transfer methods (see Ozotype, Gum-Bichromate, and also Artigue's Process) obviate the
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