This focal reducer was designed for apo refractors used by many astrophotographers. It will also work on Ritchey-Chretien (RC) and Meade ACF telescopes. The reducer provides a 0.65x reduction factor and produces pinpoint star images by correcting for the field curvature and astigmatism present in standard apo doublets and triplets and RC/ACF telescopes.
The ApexED-L was beta tested by the Chamberlain Observatory on the 14” Astro-Tech RC telescope. This reducer/flattener changed the f-stop from f/8 to f/5.2 and made significant improvements to imaging quality. The backfocus requirement for the AT 14” RC is 55mm given the scope’s focal length of 2850mm.