The Optical Magic Lantern Journal (January 1900)

The Optical Magic Lantern Journal and Photographic Enlarger. 5 The drum x revolving causes the roller 1 to revolve, the projections 2 on which engage with perforations in the film and so draw the film through the apparatus to the spool core 7 where it is wound up. At the same time the looping roller Q is being moved backwards and forwards, the effect of which is the drum x and roller 1 continuously revolving is firstly to form a loop in the film with the result that the required portion of film is drawn through the gate L from the spool 5; secondly, on the return movement of said looping roller Q that portion of film which formed the loop is drawn through by drum x and roller 1 without moving the film in the gate or unwinding from spool s. The shutter 0, continuously revolving, is so arranged that when the film is stationary in the gate the openings in said shutter are opposite the gatc and permit the passage of light through the apparatus, whilst when the film is moving the segments in shutters are opposite gate and so intercept the light. The various parts driving the looping roller are so proportioned as to always keep said looping roller in contact with the film, and the looping roller being also mounted on the same spindle as the drum x, its distance from periphery of said drum will be constant. It ~ bound with tape all round. A frame is made of : mixed with some _ one is very great indeed. will therefore be seen that the strain upon the | film while passing through the apparatus will be normal, unevenness will be rendered impossible, and the danger of tearing the film reduced to a minimum. When a film is to be rewound, the spool 26 is placed on spindle 27, and the core 25 on spindle 23. The rewinding may however be done whilst another film is passing through the other side of the apparatus.—14861 of 1897. Lantern Screens, Sheets, Frames. By THOS. J. SMITH. OR ( Yygi?N HE words “screen” and “sheet” 9 x being often used indiscriminately, what is known technically as one, and the other. of some material which ought not to let window blind fashion on a batten and be at the bottom. A sheet is, or ought to be, made of closely woven linen or calico (which is to be had up to 9 feet wide), stitched together | to form the required size and hemmed and ' and | perhaps it will clear the air to state | A screen is made | any light pass through, and is fixed | wood or bamboo in suitable lengths, rather larger when put together than the sheet, which ig then stretched on it till not a crease or wrinkle is visible. The screen is the best, but awkward for travelling. The sheet and frame being portable are the best substitute. All screens should be recoated each autumn with a wash of pure Chinese white, or else whiting size and a little blue, the latter being cheap as well as good. Sheets if soiled in, the creases or otherwise rather dirty should be washed. They will let more light through than before, but are far preferable to a dirty or marked sheet which the greater light only shows up the more. A good sheet with care will be passably clean for two winters, and all who value the best results would do well to sell their soiled one, when washed, for a fair sum and get a newone. The difference in cost will repay itself in much finer results. Doubtless to some the use of a frame will seem unnecessary, but the difference between pictures on a tight sheet and a hanging This will be apparent from the fact that a perfectly white, smooth, opaque surface, free from cracks, creases, streaks or other marks, is absolutely the best . for lantern work. Supposing then that some ‘readers are already after something better . than they have hitherto put up with—and it is astonishing what some lanternists, and still more some audiences will put up with— the question should be asked: What kind of article will best serve our purposes? for in ; this connection it is a fact that the same sum will procure the most suitable, or in some , cases absolutely the most unsuitable article, ; appearance and results. and yet in each case the buyer may have intrinsically full value for the money paid. Firstly, if the displays are in one building, a roller screen is by far the best for convenience, For use at home or in small rooms, a very good and cheap one is of white cartridge paper, that obtainable at artists’ repositories, 5 feet wide. This with a lath top and roller bottom, mounted like a map, or even two pieces of suitable picture framing, is excellent. Then there are the reversible cloth ones, of a kind of slate colour on one side | for a background in photography, and with a roller; the latter being usually heavier, should | white surface on the other side for use with the lantern. Coming to larger sizes, if economy must be strictly considered, stout sheeting, well sewn and well hung on roller and batten, with two or three coats of propsr whitewash