The international photographer (Jan-Dec 1935)

Eight The INTERNATIONAL PHOTOGRAPHER October, 1935 Miniature Photography PICTURES ON SCREEN Lantern Slide Comes Back By Karl A. Barleben, Jr., F.R.P.S. |HE lure of the old-fashioned magic-lantern persists even today in the form of amateur movies — 8 mm. and 16 mm. movies — which thousands of amateur filmers enjoy producing and showing on their screens at home. It is a far cry from the still lantern slide to movies, nevertheless, they are basically similar. While home movies satisfy a very definite need in the average home, it cannot be denied that some forms and types of pictures are best presented in the form of still pictures; lantern slides. It is said that there is nothing new under the sun, and that history repeats itself. This must be so, to a certain extent at least, for a surprising increase in the popularity of the old fashioned lantern slide, brought up-to-date, is quite noticeable. The continued use of the miniature camera of the Leica type can be largely credited for this, because the lxl Vi inch negative area on standard 35 mm. cine film makes it easily possible to produce film and glass slides by contact with extraordinary economy. Let us for a moment look into this matter — we may find something of decided interest. Beginning with a strip of negatives lxl Vi inches on 35 mm. cine film, we have several avenues open to us; we can make contact prints on paper, which are rarely completely satisfactory owing to their small size, make enlargements of almost any desired size, or make transparencies either on film_ or glass for the purpose of showing on a screen a la magic lantern. The transparency possesses, as anyone who is familiar with them will agree, a remarkable brilliance which is totally lacking in any paper print process. There seems to be a clarity, depth, and wealth of detail in them that is nothing short of remarkable— to say nothing of interesting. Two methods of making and using transparencies present themselves: film slides, and glass slides. Film slides are so well-known that it would be but a waste of time and space to go into a description here. The glass slide, however, is not so well-known. The standard miniature glass slide measures 2x2 inches, a happy size which permits great flexibility. The regulation standard glass slide measures 314x4 inches (in England, 3V4X4V4 inches square). The small 2x2 inch glass slides are made and supplied by several American and European plate manufacturers, hence, are obtainable everywhere. For the printing of positive film strips, the Eldia printer stands quite alone as an instrument for quickly and accurately making picture areas of 3/4xl inch (standard motion picture frame area) and lxl ¥2 inch. Pictures can be printed on the positive film in any order desired, regardless of their sequence in the negative strip. This is invaluable, as can be readily seen, for rarely do we make a strip of negatives in their proper sequence in the camera. When it comes to making glass slides, the Eldur printer stands supreme. The Eldur is similar in its design and operation to the Eldia except that it provides for the accommodation of 2x2 inch glass plates instead of a strip of positive film. For commercial finishers, lecturers, and the like, who have large quantities of slide material to make more or less regularly, the Laver printer is suggested. It is a most versatile piece of apparatus, capable of making either positive film strips or glass slides at will. Naturally it is somewhat more costly than either the Eldia or the Eldur printers. These printing devices are designed especially for the production of miniature projection material, and may be secured from any local dealer or direct from E. Leitz, Inc., 60 East 10th Street, New York City. Some workers favor the use of an enlarger, such as the Valoy or Focomat, instead of one of the contact printers mentioned, because by enlarging the negative image somewhat, objectionable areas of the negative can be eliminated, important sections made larger, and in general greater flexibility is afforded. Where the prints are made by direct contact, the positive must of necessity be exactly like the negative, and this is not in all cases desirable. When using the enlarger for positive printing it becomes necessary to introduce a short extension tube between the lens and enlarger in order that a sufficiently small degree of enlargement be successfully produced. Such tubes are available. This of course refers to the use of the usual 50 mm. lens which is commonly used in the enlarger. The use of the extension tube can be entirely eliminated by using a long focal length lens, such as the 135 mm. lens. This will produce a sharp image at only slight enlargement of the image. Various methods are in use; a few making good use of the Laica camera itself as the printer. In such a case the positive film (for making film slides) is loaded into the camera and the camera lens is removed. The image in the enlarger is projected down into it through the lens aperture, and the camera shutter makes the exposures. This method works out very well, but obviously it cannot be used when making glass slides. When making glass slides, the glass plaie is centered on the enlarging easel and the image projected directly upon it -after the image has been adjusted and arranged to conform with the desires of the worker. Many other methods will come to mind as one thinks about the matter, and the best method for the individual is the one which seems to be easiest and most practical. This is obviously a matter for the individual worker to decide for himself. The details of actually making positive material for projection are the same as in the case of making similar material for standard projectors (3'/4x4 inch slides), hence the reader is referred to literature dealing with the subject of lantern slide making in general for specific details as to procedure, formulas, etc. It is the purpose of this article to merely point out a few of the advantages of using the miniature equipment for this purpose. One of the most vital problems which has not as yet been ironed out is whether to make and use film slides or glass slides. Surely the former have very decided advantages; a film slide of fifty or more pictures can be carried in the vest pocket without inconvenience; it cannot break; it is light in weight, weighing hardly anything at all; and it is very cheap to make up. On the other hand, one cannot change the sequence of pictures once they are printed on the film slide, and most important of all, the film is subject to deterioration and scratching — this being the one outstanding fault which can be found to count heavily against film material. As to scratching, however, Teitel's new Scratch-Proof Solution, which was introduced for the first time to amateurs late in July, 1935, has done a great deal to eliminate this evil. The Scratch-Proof Process has been used for years by the major motion picture producing companies as a preservative on their valuable master-negatives and positives. The process was a secret one, and was not released to individuals until last July, as previously mentioned. Now, however, it is supplied in bottles to the trade so that the individual may avail himself of its remarkable properties. Briefly, this solution impregnates the emulsion with certain oils or waxes which render the film so tough that it requires a sharp instrument to make anything like a scratch on it. "Ain't that sumthin'?" Frankly, Teitel's Scratch-Proof Solution is the answer to thousands of miniature camera enthusiasts' prayers for not only their positive film slides but valuable negatives as well. It is nothing more than the frequent rolling and unrolling that in time causes scratches to appear on the film, and once this is overcome, the film strip is in a fair way to become immensely popular. The glass slide of 2x2 inch size, it must be noted, has its own particular advantages. The slides are very inexpensive, and because of their small size do not break or crack so readily as the larger ones, even when dropped on hard surfaces. Then Please mention The International Photographer when corresponding with advertisers.