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Towler, John. The Silver Sunbeam. Joseph H. Ladd, New York: 1864. Electronic edition prepared from facsimile edition of Morgan and Morgan, Inc., Hastings-on-Hudson, New York. Second printing, Feb. 1974. ISBN 871000-005-9

Chapter XXI.
MELAINOTYPE-FERROTYPE.

THE melainotype takes its name from the black background upon which it is taken. Ferrotype from the iron of which it is composed. Very thin plates of sheet-iron are covered with a protective varnish or Japan, of which one is of a rich black or brown-black color, highly polished, and without flaw, for the reception of the collodion and the collodion picture. Glass in this sort of picture is entirely dispensed with, and so is also the black Japan, the black velvet, and paper. This type is by far the easiest and the quickest to take, and in general the most satisfactory when taken. Melainotype plates of all the variable photographic sizes, and of variable qualities, can be obtained from the photographic warehouses. The Excelsior plate and the Eureka plate in my opinion are the best; the Ferrotype is very good, and much cheaper.

Operation.

With a fine flat sable pencil dust off any particles from the black surface of the plate, and then flow it with collodion in the same way in which the ambrotype glass was covered. Wait for the congelation, or partial desiccation of the film, and then immerse it in the silver until it assumes a creamy opacity, (not blue,) and until the solution flows off without apparent oily streaks. Then raise it from the bath; allow the superfluous fluid to drain off into the bath, and with bibulous paper remove the last drop from the pendent corner of the plate. The plate is next inserted in its holder, and a piece of the same size placed over it. Previous to this part of the operation, the photographer must never forget to clean out the lower corner of the plate-holder, by means of blotting paper or old rag. Nitrate of silver is apt to settle in these corners; and these being formed of separate pieces of glass, cemented together, and not of one solid mass, (which is Lewis and Holt's patent,) the nitrate of silver becomes frequently decomposed by the material of the cement, and running up the plate on the collodion side by capillary attraction, it produces dark-colored stains and streaks. Make it your duty, therefore, a part of the collodion operation in fine, to clean these corners carefully before you take out the plate from the silver bath.

The time of exposure of a melainotype is the same exactly as for an ambrotype. All the instructions, too, for developing, fixing, coloring, and varnishing the positive on glass are valid here. I regard it as preferable to color after the plates are varnished, both in this as well as in the preceding type. Owing to the better conducting qualities of heat in iron plates over those of glass, more caution is required lest the Japanned film becomes raised into blisters. This misfortune is very common with beginners on certain plates, with the Excelsior, perhaps, less frequently than with some others.

This type is mounted with glass, mat, and preserver, and fixed in a case like an ambrotype; or it may simply be covered with a mat, and thus prepared for mailing in a letter. For this purpose each corner is cut off with a pair of shears, at a distance of one quarter of an inch from the apex, and the corresponding corners of the mat are folded or reduplicated over and under it, so as to form a compact piece out of the two. The melainotype, as thus taken directly from the model, is an inverted picture, like the ambrotype, but, unlike the ambrotype, it can never by a single operation be otherwise. In the alabastrine process just described, the ambrotype, it will be observed, is not an inverted picture; the plate is inverted, and the image is beheld through the collodion in its natural and direct position.


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