Traditionally, optical designers have had to make serious compromises when designing macro lenses of longer than normal focal lengths, sacrificing resolution and contrast as the focus approaches infinity in order to optimize performance in the near life-size (1:1) focusing range. In addition, its very high speed for a lens of this focal length makes it a remarkable all-purpose lens especially suited to portraiture. The lens allows a greater working distance from the subject than shorter focal length macro lenses. Tests for resolution and contrast from infinity to life-size (1:1) reproduction give this lens some of the highest overall axial to corner ratings yet obtained for 35mm macro lenses. Its sole function is to compensate aberrations produced when the lens is moved from the film plane for life-size photography. This macro corrector-lens adapter is not a magnifying lens. Using the concept of a null lens, borrowed from astronomical optics, the designers then created a 3 element macro corrector-lens adapter that achieves a true flat-field image, high resolution and excellent contrast from 1:2 to 1:1 reproduction ratio. The extremely stringent performance demands for this lens also required the use of optical glass of very high indices of refraction and some uncommonly thick elements. To achieve and maintain very high levels of performance from infinity to life-size, Vivitar designers used a unique 8 element / 7 group configuration, utilizing a patented rear corrector group to bring aberrations to an absolute minimum and to stabilize them throughout focusing distances from a reproduction ratio of 1:2 to infinity. But a macro lens must provide near-absolute edge-to-edge sharpness and a true flat-field image, with excellent contrast, especially in the difficult 1:2 to 1:1 reproduction range. Many lenses will give acceptable images of three-dimensional objects at close focus. **) Some basic information is missing in the specification as it was not provided by the manufacturer.Ī true macro lens is not merely a lens that focuses at very short distances.
#VIVITAR SERIES 1 MANUAL METERING INSTRUCTIONS SERIES#
Vivitar Series 1 booklet (August 1976).800mm f/11 Solid Cat mirror lens (Perkin-Elmer mfg.*) Sources of data: Manufacturer's technical data.600mm f/8 Solid Cat mirror lens (Perkin-Elmer mfg.).90mm f/2.5 macro with 1:1 optical converter.Vivitar Series I lenses represent the top products in Vivitar history. Vivitar 90-230mm f/4.5 Close Focus zoom.Vivitar 35-105mm f/3.5 Close Range zoom.The company was bought on Novemby Syntax-Brillian Corp., then on Augby Sakar International. Though never a camera manufacturer, it has sold cameras under its own label since 1975. Over the years, Vivitar became a multinational manufacturing and marketing company with subsidiaries in Japan, West Germany, France, Canada, the United Kingdom, the Netherlands, Belgium, and Switzerland. in 1979 upon the success of its leading brand name. The corporate name was changed to Vivitar Corp. Originally founded as Ponder & Best, Inc., the company was established in Hollywood in 1938 as a distributor of photographic products by the German immigrants Max Ponder and John Best.
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