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Mounting a Telrad

Started by Rich Sulenski, 04/15/2004 10:13AM
Posted 04/15/2004 10:13AM Opening Post
What is the correct process for mounting and aligning a Telrad. I purchased one on ebay with a base but I want to be sure to align it with my telescope when I mount it.
Posted 04/15/2004 03:49PM #1
There's really nothing to it:

The near end of the Telrad which faces you has three knobs for adjusting the placement of the bullseye reticle, so you have plenty of "wiggle room" for aligning the telrad image with your view thru the eyepiece. As I recall, padded sticky tape comes affixed to the Telrad base. Just carefully eyeball the parallel placement of the Telrad on the tube of your scope at a convenient location, lining it up parallel with the optical path of the scope as best you can visually. Reasonable care should be sufficient; as I said, there's plenty of available adjustment. What's actually more important is determining the best placement for the Telrad. You don't want it to interfere with your head as you view thru the eyepiece, yet you want it to be easily accessible to look thru. I'd suggest trying several positions of the entire Telrad unit on the optical tube prior to committing yourself by removing the protective backing off the tape. Once you determine where you want to place the Unit, you might want to make little pencil marks on the optical tube to guide you when you press the base with the tape onto the tube.

Whenever you mount the main part of the Telrad prior to an observing session, just swing the scope onto a stationary object, like a treetop or mountaintop during the day, or polaris at night. Using your widest angle eyepiece, sight in the top of the tree or whatever, then tweak the three adjustment knobs on the back of the Telrad to align the bullseye display with what you see thru the scope eyepiece. Use the same procedure to align an optical finder that magnifies as well: First put the scope on a known stationary object, then adjust the finder.