REAL HELP FOR SCT OWNERS

The Design and Calibration of Schmidt Cassegrain Telescopes

This document may be of interest to owners, or future owners, of Schmidt Cassegrain Telescopes (SCT), especially those who also have ccd or photographic attachments. Finding no really useful in-depth book that covered the essential SCT equations, optics, aberrations, and the complete laws for focal reducers, I have spent some months compiling that reference. It is now available at a small cost for production and shipping(US$20). For details of how to get your copy, follow the Contents link below for the index of this 87 page document.
Summary
This document covers the practical aspects and measurements of a Schmidt Cassegrain telescope (SCT) with sufficient design backup to enable interested amateur astronomers to fully understand their telescopes. It covers the concepts of the basic optics, the design of the Schmidt plate, the effects of optical aberrations, and the addition of focal reducers. It includes the accurate measurement and calibration of your telescope. It answers many of the awkward questions such as what is the expected movement of the focus per turn of the focus knob, and how does the focal ratio of the SCT change when one adds extension pieces such as 2" diagonals, extenders and focal reducers, ccds and cameras.