The Optical Magic Lantern Journal (November 1895)

184 The superiority of coloured pictures over plain photographs as a means of entertaining the general public in a lantern exhibition is admitted by all lanternists of experience. Even the finest uncoloured slides become monotonous to an audience after @ score or so have been exhibited, while the varying effects of colour producible in the skies of landscapes, and in the details of most pictures, impart a charm which is always appreciated. Slide painting in its higher branches requires great skill and experience; there are trade secrets in the business, by which special colours are produced, and certain effects obtained, which to a beginner seem to defy attempts to imitate them ; in short, the art presents special technical difficulties, with which I propose to deal. The simple tinting of a good photographic slide is not difficult, provided that the proper materials are at hand, and the right method is adopted. There are two systems of colouring slides ; oil and varnish colours may be used, or we can employ water-colours. Professional slide-painters generally use varnish colours, and there is no doubt that these are the best, because they are the most durable. Water-colours are capable of fine effects, but they should be always protected by a coat of varnish. The heat of a powerful limelight, such as would be used in a first-class exhibition, is considerable, and only varnish colours will stand the ordeal without detriment. Brilliant tints can also be produced by dyes, and gelatine slides may be coloured by simply staining the film; but this is the lowest class of colouring, and no lanternist of experience would buy such slides, for they are sure to deteriorate if often shown by limelight. Some dyes are much more durable than others, but the safest plan is to avoid their use as much as possible. Varnish colours are pigments mixed with a varnish ; oil colours are the same pigments ground in a slow-drying oil. For lantern slides | there.is no dowbt that varnish colours are the best; they’ dry quickly, and are more transparent. Varnish colours Gan be obtained from lantern opticians and from slide painters. If these are not obtainable the ordinary artist's oil colours may be employed. © There are some transparent colours included in the series of oil paints sold bya few firms which are valuable to slide painters, and a few remarks upon these may be useful. Prusstan Blue.—This is invaluable for skies and all stippled tints. It is perfectly transparent, rich'in colour, and: remarkable for its intensity, a very thin layer of the pigment pro The Optical Magic Lantern Journal and Photographic Enlarger. ducing a powerful colour. This property of intensity renders it easy to produce tints even of any depth by the tapping action of the finger tip, called ‘ dabbing,” which spreads the colour over the glass in a layer so even and smooth as to be comparable with stained glass. Prussian blue has a slight greenish tint, especially when viewed by artificial light; this may be corrected by adding a trace of crimson lake, mauve, or French ultramarine. For moonlight skies a little burnt umber or lampblack is frequently added ; while for evening effects, just after sunset, the colour can be used pure. Good purples and violets may be obtained by mixing Prussian blue with mauve, crimson lake, or pink madder ; brilliant greens by uniting it with any of the yellows ; and sober greens by combining it with burnt sienna and the brown pigments. In short, Prussian blue is an indispensable colour to the slide painter; it dries quickly if mixed with mastic varnish or other suitable medium. Antwerp Blue is equivalent to Prussian blue, diluted with magilp; it has no special advantages, and although an excellent colour in itself, yet with Prussian blue at our service, it is practically useless to the slide artist. French Ultramarine—This blue is quite transparent and free from any green tinge, even when viewed by oil-light. It is useful for making purples by mixture with pink colours; it has little intensity, dries rather slowly, and is better adapted for brushwork than for dabbing. Crimson Lake.—This colour is the best red available to the slide artist, but it is not so perfect as might be wished. It has little intensity, and is capable only of comparatively pale tints in the dabbing process; deeper tints can be produced with the brush, but owing to a slight translucency of the pigment the colour is apt to looker darker on the screen than it appears on the slide. However, some crimsons are much more transparent than others, and if prepared in varnish instead of oil, satisfactory results can be obtained. Criinson lake in oil dries slowly. A good scarlet is obtainable by mixing crimson lake with gamboge; and flesh tints by adding it to burn sienna and the brown pigments. Madder Lake and Rose Madder.—Madder lake or pivk madder is very similar in tint to rose madder. They are beautiful colours, permanent and perfectly transparent, and give brighter reds on the screen than crimson lake. : Being very weak in colouring power, they are useless for dabbing. It is necessary to pile on the paint with the brush before any approach to a deep red is obtained. Prepared in oil, they require weeks to dry, unless a drying oven is