The Optical Magic Lantern Journal (November 1900)

The Optical Magic Lantern Journal and Photographic Enlarger. 145 should be mostly from above, so as to avoid shadows on the print. vides excellent lighting if the print be placed fairly close to the window, the lower portion of which is shaded. A second arrangement of title slide is to include a small picture, and the necessary wording by the side in black and white. This calls for the exercise of a little skill in draughtsmanship in the lettering, as well as in any decorative work which may be done. But an artist friend can generally be prevailed upon to supply the latter, which should be separate from the picture. The black and white work should be copied and printed on a lantern plate, space being left for the picture. This is printed (from a masked negative) on to a separate slide, and the two bound together. In this way a very pleasing effect can be given by toning the picture slide to a warm or blue tone, which again can be made to give rise to further novel effects by staining the black and white slide faintly with aniline dyes. A still further variety can be produced by placing several small views of different colours on the same slide. Unfortunately, the only really practical method of doing this is to make the little pictures by reduction on separate lantern plates; to then tone them, to cut them up with a diamond, and to afterwards affix them to one piece of 31 by 32 inch glass. But this means that a black mask must be used to hide the sides of the glasses, and the title must therefore occupy a rather subsidiary position in a space provided for it in the mask. Transparencies on slow celluloid films might be tried instead of glass, and ought to allow of a white background being obtained. The subject of the picture may bear humorously or punningly on the title of the lecture. For example, a title slide on ‘‘Matches” may have for its accompanying illustrations Maud and Algernon in Mayfair, or Edwin and Angelina ‘‘ Margate way.” The advisability of this depends on the audience. Hence the usefulness of a selection of title slides. An easy method which may be commended to those whose skill in drawing is of the slightest, is to obtain a placard or poster in | ' new reducer would do for them. some way bearing on the subject, and by working in photographic views of their own to make a suitable mosaic. Thus, fora set of slides | ‘ about as much as would lie on a threepenny of a certain district, one can generally find a title slide in the bill issued by the railway company which serves the district, or by the local authorities interested in popularising it. An ordinary room pro| Reducing the Density of Lantern Slides. By T. PERKINS. \ HE introduction. of persulphate of ammonia as a reducing agent is likely to be a great boon to the makers of lantern slides, and many slides that would otherwise have SY) been only fit for conversion into cover gh glasses, may be saved for their intended use. With this new reducer and Howard Farmer’s, almost any over dense slide can be reduced so as to fit it for projection on the screen. Let me detail some of my late experiences. I had a box of ‘“‘Gaslyt ” lantern plates given me for trial. I exposed these in a printing frame under various negatives, and found that I got them sufficiently exposed by holding them out-of-doors on the shady side of the house in the forenoon of a sunny October day, for periods of 3 to 10 seconds, according to the density of the negative. I had not by me the chemicals to make up the rather complicated developer, recommended by the makers, so used the following which I had by me already made up. A. Hydroquinone .. bse 4 ounce. Meta-bisulphite of potash # ounce. Bromide of potassium 60 grains. Water ee . 20 ounces. B. Caustic soda a 3 ounce. Water .. . 20 ounces. I took one drachm of each, and made up the solution to an ounce with water. With this developer I obtained warm browns, and the addition of a few drops of a 10 per cent. solution of bromide of potassium gave a redder colour, somewhat resembling burnt sienna; when using this, I gave the longer exposures of about 10 seconds. Tn some cases I found that before I got out the delicate detail in the high lights, the shadows were far too dense, so that all detail in them was lost. The slides in that condition were absolutely worthless, but as an experiment, I fixsed and then washed them for several hours in four or five changes of water, and left them in water all night until I had time to see what the I took with a knife from the bottle of persulphate of ammonia some crystals without weighing them, but piece, and dissolved these in an ounce of water, and then put the over dense slides in the solution one by one. At first no reduction