The Optical Magic Lantern Journal (July 1890)

— ae fhe Optical Magic Lantern Journal aud Photographic nlarger. v. MARION & Co., 22 & 23, Soho Square, London COW AN’S Gelatino Chloro-Bromide Plates. (MARION & Co., SOLE PROPRIETORS.) Specially prepared for making transparencies, in the Camera, or by Contact printing mith gas or other artificial light,. alsn eminenily snitable far reproduction uf negatives and general copying purposes. 32 by 34 1/0, 44 by 34 1/0, 5 by 4 1/7, 6} by 43.2/3, TE by 53/5, 8h by 41 4/0, SH by GS 4/3, 9 by 7 3/0, 10 by $ 7/3 12 by 10 10/0, 13 by 8 10/0. These plates are much slower than the ordinary Bromide used for Portrait and Landscape work, but much quicker , a ( 4 : ' minutes wili be required. found to give, witi full exposure, very brilliantimages with . than the pure Chloride Plates ; In the camera they will be clear glass in the unexposed parts, making them specially valuable for general copying furposes. The exp-sure for contact printing by gaslight (using an ordinary Hshtail burner at 12 inches distant) varies from 10 to 15 seconds upwards, according to the density of the Any other Sizes to Order charged in same proportion. negative: and with the camera, using lens with diaphragm about F24, and reflected sky as a source of light, 1 to 2 Any developers may be employed that work well with Bromide Plates, but the following are recommended :—The proportions are given for 10 ounces of developer only, so that by easy calculation each one may mix the quantity best suitiug his requirements. COW AN’S Gelatino-Chloride Plates. MANUFACTURED AT SOUTHGATE BY MARION & Co., 22 & 238, Soho Square, London, W. By by 35 1/0, 44 by 34 1/0, 5 by 41/7, 64 by 43 2/3, 74 by 5.3/5, S} by 44 4/0, S4 by 64 4/3, 9 by 7 5/0, : 10 by S$ 7/3, 12 by 10 10/0, 13 by $ 10/0. These plates in appearance difter entirely from the usual Bromide tilms, being very transparent, and ofa deep orange colour by trausmitted light, but are capable of development to any density required. : Though extremely sensitive to daylight, they are much less so to gaslight; so that moreartificial light may be used during development than with Bromide Plates. i his will be found to be of great advantage, as the plates may be examined from time to time within a reasonable distance LANTERN SLIDE MAKIN This Camera meets the long-felt want for an [nstrumevt that is always ready at a moment's notice to produce Lantern Slides from the Photogras:her's Negative. The usual preparations necessary (especially in the case of Amateurs) to take a Lantern Slide are only too well remembered for their inconveniences and vexations. Hither the focus is found to be not quite satisfactory, or the intended amount of picture is not on the plate, ur something else is wrong, with the result that it is very commen to take several slides befo:e a perfect ove is secured. _ With this Camera such mistakes and difficulties are impossible, as it is pied accurately in perfect Jncus, size, and position. All that is required to expose a plate being to insert a negative iu the grouves at one end (film towards the lens), and in the dark room put a lantero plate iu the carrier provided for it at the other eud, the caps effectual:y excluding all light except that passing through the lene. No dark slide or lens cap is required. _ When the Negative and piate are in position, the Camera 18 carried out and pointed to the light, the exposure being 1 or 2 minutes, according to circumstances. The Camera is then carried back to the dark room, and the lantern plate taken out and developed. | ofagas Hame,and the density thus regulated toa great nicety.. The exposure to diffused daylight will vary from ] to 5seconds upwards, according to the density of the negative. For the reasons mentioned above, it is not recommended to make the exposures to gaslight, but a very reiable method, whep a number of pictures are requirea exactly alike—or when it is necessary to work at nixht—is to burn a few inches of maguesium ribbon at from 6 to 18 inches from the negative, according to its density. (PATENT APPLIED G CAMERA. FOI) “Tks. The Instrument is made in three sizes :—the smallest making slides trom 4-plate negative; the nextiniking them from 1-1-plate negative ; and the largest, an adjustable one, taking all sizes. from 12 by 10 downwards, must useful to the professional—but it must be remembered it reiuires setting for every size, like ordinary Cameras. ‘The charm in always working from one size negative is, that there is never any setting to do. Prices complete with excellent lens, 3-plate, 12/6. 1-1-plate, 15;-. 12 by 10, adjustable to any size, 21/-. Nore.—Lantern Slides being square. it is usual to copy a square of the negative. ‘hese Cameras are square, and take in the full width of the negative, and an equal extent of the length; but when desired they are made the same shipe as the negative, so as to take in the whole of it—it then being of course necessary toemploy a specially shaped mask to mount the slide up to advantage. We provide mask of the required shape. The latter form of Camera is 2/extra on the half-plate, and 2/3 extra on the whole plate. GRIFFITH’S ECONOMICAL ENLARGING CAMERA. Having received a considerable number of enquiries and requests for an Enlarging Apparatus of the same style as the Lantern Camera. we have had a modification made which Is properly adapted to enlarge from the ordinary negative.10 a simple, quick, and effective manner, waking the productiou of Enlargements as easy and pleasant an Occupation as the Lantern Slide Camera has rendered Shde making. ; either 3-plate or }-plate negative. Its outward appearance and size is very similar tothe 12 by 10 Lantern Camera. One end has a carrier to hold A good and suitable lens is mounted iu the sliding partition in the mididle of Camera, while the other e :d ‘‘draws out’ to focus, and is fitted with a specially: designed “dark slide,” in which either paper or glass, and opal plates, may be held for exposure. Price Complete, with lens, 30/-; packing extra, 2/6, MARION & Co, 22 & 23, SOHO SQUARE, LONDON, W,