127mm f/9.4 OTA Construction - 127mm f/9.4 Optical Ray Trace (whole)

 

The Ray Trace for the 127mm f/9.4 "BGRP" Refractor... (Click for enlarged view)

 

Here we have the complete ray trace for the 127mm f/9.4 "Brigadier General Richard Pierce" refractor draw on brown packaging paper. The ray trace helped to formulate and determine a number of aspects for this telescopic instrument. In so doing, it was determined that the main tube length would be 35.5" inches, based on the use of a 2" Sky-WatcherŽ dielectric star diagonal and a focuser from a MeadeŽ 127ED racked all the way in with 2.1" of back focuser. Another matter the ray trace tackles is the placement of the four baffles that will be installed in the main tube. With this particular instrument, I decided that I was going to use it for astrophotography as well as visual use. That being the case, a "Desired Field Size" of 1.2" inches would be satisfactory to encompass the CCD chip of my Olympus Evolt E-500 DSLR. The opening in the baffles were cut to allow for this. Please click on the image above for a closer look to see what I mean.