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Baader Planetarium Alan Gee Mark II Telecompressor

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SKU: BAD-AGII
$275.00

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Baader Alan Gee Mark II Telecompressor

The Baader Alan Gee Mark II Telecompressor solves a common problem that plagues owners of most popular Schmidt-Cassegrain telescopes. That problem was: the narrow field size and high magnifications produced by their slow optical system (typically f/10). Until now, owners of SCTs have lacked a truly versatile and high-quality method of reducing their f/10 (or slower) systems for faster, wider, photographic/CCD and visual fields.

The unique design of the Alan Gee Mark II Telecompressor by Baader positions the lens elements several inches inside the telescope's central baffle tube. The result is a sharp, wide, flat field, at a fast focal ratio of f/5.9 and it even works superbly with Baader Planetarium, Zeiss, and Celestron Binocular Viewers! Using the Alan Gee with 1.25" eyepieces can yield actual fields of view that match or exceed what you could only achieve with expensive 2" eyepieces! Baader Planetarium has developed a truly unique and extremely versatile telecompressor system that delivers the finest wide flat fields your SCT is capable of. The key to the Alan Gee Mark II Telecompressor is its innovative optical and mechanical design. It was engineered specifically to work well with SCTs in a wide variety of visual and imaging configurations.

Note: This telecompressor is not intended for use with the Meade native f/6.3 SCTs.

The Alan Gee Mark II Telecompressor is made with typical Baader Planetarium attention to detail and flexibility. Designed by Roland Christen, the optical configuration consists of a matched, wide air-spaced doublet, utilizing lenses that are precision polished to the very edge, and anti-reflection coated with the finest 7 layer multi-coatings available (reflections per surface are less than 0.2%). Lenses are individually centered and painstakingly mounted into a precision cell.

The extra-large 35 mm clear optical aperture and lens cell design maximizes the field size. The cell itself is unique, with long extremely thin-wall aluminum tube surfaces, sharp V-threaded and blackened, to reduce stray light reflections. The telecompressor assembly actually consists of 4 threaded pieces; the lens cell, two 19 mm long removable spacer sections, and a flanged end-ring (plus a thin spacer ring used in some configurations).

Previously, SCT focal reducers were designed primarily for imaging or single eyepiece use, and lacked the necessary focal length and positioning flexibility to work with binocular viewers. The Alan Gee Mark II Telecompressor has been designed to work perfectly in concert with the Celestron and Baader Planetarium Binoviewers. Now, you can turn your SCT into the ultimate large aperture wide-field "binocular telescope!" Imagine the stunning wide-field binocular views that your telescope will deliver: Up to a 1.2° field in a Celestron C8 or 0.7° in a C14 - using the Baader/Zeiss Giant Binocular Viewer; that's almost a 3X improvement in field area! Please Note: The close coupling required for the Telecompressor to reach focus with binoviewers limits it's use to only the Baader/Zeiss, and the Celestron binoviewers.