Wood, Photographing upon
To develop the exposed plate, it should be fixed upon a pneumatic holder and a little of the developer poured evenly on to the surface, and gently rocked backwards and forwards till the image ft sufficiently developed, when it may be poured off. The image nearly always requires intensification for negative work, and the following may be used : -
Ferrous sulphate ............ 5 grs.
Citric acid...............10 ..
Distilled water ......... ... 1 oz.
Add immediately before using a few drops of
Silver nitrate ...... ...... 10 grs.
Distilled water ............ 1 oz.
Pour on to the unfixed negative, and rock backwards and for-wards till dense enough. Then fix in
Potassium cyanide...... ... ... 120 grs.
Distilled water ............10 ozs.
Wash thoroughly, dry, and varnish. Those desiring complete instruction in the wet collodion process should obtain Mr. Chas. W. Gamble's " Wet Collodion Photography," published at the office of The Amateur Photographer.
Wide-Angle Lens. See Lens.
Wood, Photographing upon. This is mainly of interest from the point of view of furnishing a guide to the wood engraver and to replace the old custom of sketching the subject on the whitened block of boxwood. As the kind of drawing which the wood engraver generally prefers is one in tint and wash rather than line, the photograph forms the most satisfactory kind of guide; but any method in which a film is put upon the block, or in which liquids are freely used is unsatisfactory, as a film interferes with the freedom of the engraver in working, and liquids swell the wood and make the surface rough. An old method, suggested in 1858 by Sir William Crookes, is to rub a little of the white precipitated oxalate of silver upon the wood block. Supposing that the block is four inches square, as much oxalate of silver as will lie on a threepenny-piece will suffice. This having been sprinkled on the surface of the wood, it is well rubbed on with a