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Vivitar Series 1 600mm f8 solid catadioptric telephoto lens

This lens represents three major advances in catadioptric lens design. it offers the photographer extreme compactness, inherent environmental stability, and superior relative illumination; characteristics that have until now been unattainable in long focal length reflex lens for 35mm photography.

The optical design of the all-spherical 600mm solid catadioptric lens is derived from the Cassegrain telescope objective used extensively in astronomical work. The extreme Series I 600mm solid catadioptric lens compactness of this lens is attributed to the achievement of a seven-to-one ratio between focal length and barrel length. This compares with a 1.2 to 1 ratio for traditional non-mirror telephoto lenses and about four-to-one for previous reflex lenses. The short physical length of this lens helps to lessen the effect of minor in-camera vibrations such as mirror bounce on image sharpness. Highly acceptable hand-held shots at relatively slow shutter speeds are entirely possible. The photographer can safely violate the rule for normal telephoto lenses that minimum shutter speed should approximate focal length in hand held shooting. (A 600mm lens would require 1/500 second or faster shutter speed.)

Stability has been another major problem in catadioptric lenses. In conventional designs, the optical groups of the lens are separated by large air spaces. Temperature variants often create serious optical alignment anomalies, decreasing sharpness. These lenses are also susceptible to severe mis-alignment caused by minor shocks and vibrations. In the 600mm f8, spherically shaped elements are pieced together to form what is a virtually solid element. As all the optical elements share similar temperature coefficients, the lens is temperature stable even in extreme climates. This near-solid construction also makes the optical alignment highly resistant to damage from impact.

The troublesome "hot spot" present in conventional mirror lenses is almost entirely absent in the Vivitar Series I 600mm. This "hot spot" results from a difference in illumination between axis and corner of 50% or more.

But in the Series I solid catadioptric lens fall-off has been reduced to less than 30%, the equivalent of about 1/? f stop. As with all mirror telephoto lenses, the Vivitar Series I 600mm f8 is a fixed aperture lens. Exposure is controlled by camera shutter speed and the use of neutral density filters. In this lens, filters are placed behind the lens in the T-mount, thus allowing the use. of smaller Series I 35.5mm close tolerance VMC filters. But in the Series I solid catadioptric lens fall-off has been reduced to less than 30%, the equivalent of about 1/? f stop. As with all mirror telephoto lenses, the Vivitar Series I 600mm f8 is a fixed aperture lens. Exposure is controlled by camera shutter speed and the use of neutral density filters. In this lens, filters are placed behind the lens in the T-mount, thus allowing the use. of smaller Series I 35.5mm close tolerance VMC filters.

The lens focuses very quickly, since the entire main body of the lens (with primary and secondary mirrors including the afocal double) moves relative to the elements forming the Barlow group which remains at a fixed distance from the film plane. This focusing system requires about one-fourth as much axial travel as would be required if the entire optical system moved as a single unit. The lens can be rotated 360° inside its tripod mounting ring and can be locked in any position. A safety catch holds the lens securely during rotation. One more unique feature of the Vivitar Series I 600mm f8 solid catadioptric lens is its development and manufacture entirely by U.S. sources. Working with the Perkin-Elmer Corporation, a world leader in global science and astronomical systems, Vivitar has incorporated the principles of intricate astronomical optics into photographic lenses for the professional and advanced amateur in 35mm photography. The 600mm f8 is the first of a family of solid catadioptric lenses, with 800mm f11 and 1200mm f11 versions scheduled to follow. The production of Series I solid catadioptric lenses, including the 600mm f8 is an exacting, time-consuming process. Optics of this type do not lend themselves to automated, assembly-line manufacture.

They are produced individually, each lens being assembled and tested almost as though it were the first one to be built. For this reason, these lenses will be in limited supply.

Optical Specifications

Construction: 9 elements 7 groups Angle of acceptance: 4° Minimum Focusing distance: 7 meters (23 feet) Aperture range: f8 (fixed f stop)

Mechanical Specifications

Length: 8.4cm (3-5/ 16 in.) Weight: 1.36kg (3 lbs) Diameter: 10.6cm (4-3/16 in.) Filter provision: 35.5mm at the rear of the lens, inside the T-mount . Filters included are Series I VMC close tolerance: UV haze, yellow K2, 4X ND, and red 25A.

Screw-in hood, detachable tripod socket, filters, lens case , front and rear lens caps included.

Mounts available to fit Universal Thread (T-mount), Nikon/Nikkormat, Canon, Minolta, Konica Autoreflex and Olympus OM cameras. Mounts available to fit Universal Thread (T-mount), Nikon/Nikkormat, Canon, Minolta, Konica Autoreflex and Olympus OM cameras.

Vivitar Series I Program

In recent years, remarkable progress has been made in solving some of the classic problems of optical design. Intensive work in the field was spurred on by the demands of space exploration and military applications and vastly aided by the growing sophistication of computer technology.

Vivitar optical designers, working with programs devised for highly specialized optical tasks, have used computer generated designs to develop for Vivitar a new series of lenses capable of performance unreachable until now.

Each Vivitar Series I lens so far introduced represents a breakthrough in optical design. The 135mm f2.3 and the 200mm f3 are among the fastest automatic telephoto lenses in their respective focal lengths. They are unusually light and compact. Each has a uniquely positioned rear compensating element that automatically corrects aberrations at all points from the closest focusing point to infinity.

The 70-210 f3.5 automatic zoom lens and the 35-85mm f2.8 auto variable focusing lens are likewise definite advances in lens design, both offering extremely close focusing capability and remarkably compact configuration.

To come? Look for a 90mm f2.5 macro, a 28mm f1.9 wide angle, 800mm f11 solid catadioptric and 1200mm f11 solid catadioptric telephoto lenses. There will eventually be a complete optical system of more than twenty Vivitar Series I lenses, each representative of advanced technology and demonstrably superior to other lenses currently available.

Vivitar

marketed in the U.S.A. by Ponder & Best, Inc.

Corporate Offices: 1630 Stewart St., Santa Monica, CA 90406

In Canada: Precision Cameras of Canada Ltd, Quebec.