The Educational screen (c1922-c1956])

I pril, 1936 Page 131 limited only by the speed with which the photographer can i)iill the trigger. It take.s but 15 to 20 seconds to make 36 ex|5osures. Eqiiipjicd with a Leica camera and the new rapid winder, it is claimed no action will be too fast for the photographer to record. We are informed by E. Leitz, Inc.. 60 E. Tenth .Street, New York City, that a slight adjustment will have to be made on older models of the Leica camera to enable them to accommodate this new accessory. For further information the reader is advised to write to E. Eeitz. Inc. Improvements in Bri+eli+t Screens The Motion Picture .Screen cV Accessories Co. of 526 West 26th St.. New York City, announce several major im])rovements in their DeLuxe "A" Motion Picture Screen. New ideas and materials are con- stantly investigated by this company with a thought to their incorporation in P)ritelite-Truvision Screens. They have, in conjunction with one of the leading textile mills of the country, so perfected the screen cloth that it will retain its basic white for a longer period and will continually project images with greater brilliancy. A further improvement has been effected in the sim])Hfication of its operation, as the screen is now raised automatically and instantly by simplv lift- ing it u]) from the box. These improvements are in- cluded in the regular price. The manufacturers will be |)lease<l to send information to interested readers. New Camera Accessories Right up to the minute in design are a new lens hood and graduated filter, brought out by the firm of Franke & Heidecke, for use with the Rolleiflex and Rolleicord cameras. The hood, shaped for the square format of these popular cameras, is fitted with a cam- actuated contracting grip arrangement which prac- tically locks it to the lens mount. Provision is also made for holding the new 33 mm. disc filters inside the hood, which is supplied with a neatly made leather case. Their graduated filter has been so constructed that it will go over the front of the lens hood, and is thereby kept at the correct distance from the lens so that it can be really eflfective. The filter slides vertic- ally in a well made holder and in use it is first adjusted with the aid of the finder lens; then it is transferred to the taking lens for the actual exposure. No in- crease in the normal exposure time is required. F"or further information and prices, we suggest that you write to Burleigh Brooks, 127 West 42nd Street, New York City, and ask for the new edition of "Practical Accessories" to the Rolleiflex. There Is a Reason WHY LANTERN SLIDES MADE FROM KEYSTONE THIRD-DIMENSION NEGATIVES ARE SUPERIOR Lantern Slide from Keystone Primary Unit on Indians Stereoscopic photography is the most exacting and difficult type of photography. Good, clear, third-dimension requires that there be two pictures exactly alike in all de- tails. If one picture is faulty in any detail, the fusion is imperfect, and the negative more or less useless. In securing two per- fectly matched pictures, therefore, the re- sult is usually a negative perfect in every detail. There are no fuzzy corners or blurred spots in a third-dimension negative. In building up your visual program, you will do well to investigate the Keystone Units in the Social Studies—all lantern slides made from Keystone third-dimension negatives. Keystone View Co. MEADVILLE, PENNA.