GB488071A - Improvements in or relating to photographic cameras having telemeters adapted to operate as view finders - Google Patents

Abstract

488,071. Photographic range- and viewfinders. ZEISS IKON AKT.-GES. Sept. 30, 1937, No. 26524. Convention date, Oct. 3,1936. [Class 98 (i)] In a camera having a short-home-base range finder serving also as a view-finder, a partiallytransparent concave mirror is placed in the path of the rays entering the range-finder at the direct-vision end, and forms at infinity an image of markings which define the fields of view of two or more camera objectives. Each objective mount may carry its own marking, and also if desired, the concave mirror. As shown in Fig. 2, a frame 3, slidably fitted at 6, 7 to a camera provided with a rangefinder, carries a partially-transparent concave mirror 1 in the form of a silvered layer between positive and negative lenses. In a rear wall of the frame 3 is an aperture, which is disposed in front of the direct-vision aperture of the range-finder, and is surrounded by a black margin on which are marked in white two rectangles defining different objective fields. An eye looking through this range finder sees at infinity the images of these markings formed in the mirror 1. The markings may, if desired be formed on the camera front. Modifications are shown in which (1) the frame carrying the mirror is attached to the camera, and each objective carries its own marking on a frame which is rocked into position when the objective is fitted, and (2) each objective is provided with a frame carrying a mirror and the marking appropriate to the objective. Reference is made to photographic range and view-finders in which the various fields of view of exchangeable objectives are shown on a ruled plate ; to a stereoscopic range-finder having a similar field-delimiting arrangement. Specification 454,064 is referred to.