Astro-Physics CCD Focal Reducer for f/9-f/18 Telescopes

This AP telecompressor will provide full coverage of the ST10E chip with scopes ranging from f/9 to f/18 focal ratio. The 2-element cemented design transmits close to 99% of the incoming light over the range of 420 to 700 nm. The focal length of the telecompressor optics is 12 inch. For refractors, the field is compressed by 0.67x (when using a Color Filter Wheel). If you have a moving mirror system, the native focal ratio will increase. The design allows full corner-to-corner illumination of the ST-10 and ST-8300 chips with most catadioptric telescopes. This design does not add coma to the wavefront, and thus can be used with all flat-field and coma-free telescopes such as Maksutov-Cassegrains, Schmidt-Cassegrains, Ritchey-Chretiens and refractors. The inherent resolution of the telescope is not compromised when using this compressor. Please review this Telecompression Chart to see how this item will fit into your imaging system. If you want a higher compression ratio, but do not use