The Journal of the Board of Arts and Manufactures for Upper Canada, July 1867
The following practical instructions for coloring photographic and other transparencies for the lantern are extracted from a manual on the Magic Lantern, published in London.
Apparatus.
The easel, an assortment of brushes and dabbers, an ivory and a steel pallet knife, a small muller and slab, a pallet, a penknife, an etching point, lithographic pens for outlines, pieces of linen or cotton rag.
Media.
Oil of spike, lavender, turpentine, varnish, oxgall, Canada balsam.
Colors.
Italian pink for yellow, Prussian blue, Antwerp blue, crimson lake, crimson.
These are the three primary colors, which are capable of yielding nearly all the rest by judicious mixture. The colors purchased should be those prepared for oil painting, in collapsible tubes, and the purpose for which they are intended should be explained to the color maker.
The use of the muller and marble slab in well rubbing these colors down will be learned. For black, ivory or lamp black is used; for white the glass is left uncoloured; for green, Prussian blue and Italian pink; for purple, lake and Prussian blue; for orange, lake an gamboge; for brown, either burnt sienna or a mixture of Prussian blue, lake, and Italian pink.
Glass.
Patent plate and flatted crown are the two kinds obtainable. The former is expensive and only necessary to be used when something of an exceptionally superior character is to be produced. The latter will answer most purposes if the following precaution be observed: — The two sides differ from each other, one being smooth and the other having gritty particles, which may be distinguished on drawing the nail across. The painting should be done on the smooth side, or if the photograph be prepared with a view to subsequent coloring, it should be taken on the smooth side.
A good medium for mixing the colors is transparent oil varnish to which a few drops of liquor ammonia have been added.
In the case of a photograph, no preliminary outliningis required, but where it is intended to reproduce a large engraving on a three-inch disk, a reduced outline ofthe required size is first made upon paper, and this being laid under the glass, the outline is traced through with the appropriate material. This outline is then protected by a coat of varnish, the coloring then begins, the sky first and then the extreme distance, and successively the middle distance, and the foreground, increasing in intensity of color and decision of outline as the objects approach the spectator. The required depth of color will regulate the amount of varnish to be used, and small dabs should he made on a piece of glass before beginning to paint, in order to ascertain the quality, transparency, and depth of colors. The remedy for excessive opacity is more varnish and ammonia. Two or three drops may be added to a teaspoonful of varnish.
The lithographic pen is to be used for tracing the outline.
Dabbers are madeby burning down thick camel's hair brushes to a round, stumpy end.
Another and very satisfactory method of coloring consists in using aniline colors, known as Judson’s dyes; or better still, those prepared by Dr. Jacobsen for coloring photographs. In using these colors the disagreeable smell of oil and varnishes is avoided, the only medium required being water.
Before using the colors, it is imperatively necessary that the glass on which the design is either sketched or photographed should be coated with albumen. When dry it is ready to receive the colors, the albumen acting as a mordant; a plain piece of glass should also be coated with albumen, on which to try the depth of colors; and great care must be taken to keep the coloring within the outlines, as, being dyes, these colors cannot be removed.
To prepare the albumen, take the white of an egg and add to it one ounce and a-half of water, beat all to a froth, and the liquid subsiding is fit for use.
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