Mak/Newt. Collimation.

Now that my new MN-76 is nearly on the Horizon , & (If the UPS fork-lift driver doesn't have it in his front sight blade) I am asking competent Mak lovers to relinquish their
top secret method of precision collimating. This scope requires a different approach then the Newt & Dob. reflec.
So far I have heard of the Techtron kit, auto-col. light pipes, sight tubes, film can lids, lasers, & circle reticles
Gee, I miss my 102 already... Hoping some ingenious Astronomer has through trail & error, and after $$$$ worth of gagets he has since sold on the Astr-Mart, would share his technique with me and other who stumble across this thread, Thanks for your time. JM

Hi John,

There was no information when I got my MN86 several years ago, which prompted me to chronicle some of the things I encountered along the way, one of which was collimating the scope.

It's been a few years since I've visited this topic so some of the links may now be inactive, and some of the scopes's hardware may be somewhat different, but FWIW:

http://members.tripod.com/milton10/id25.htm

or

http://www.cloudynights.com/howto/maknewt.htm

Basically:

A combination Cheshire/sight-tube helps to assure the initial alignment is correct.

Though not absolutely necessary, a properly collimated laser (yes... they too need to be checked for collimation!) can help in isolating potential dynamic problems (ie: when the focuser position is changed) as well as in fine-tuning the alignment (or as quick check).

In my own view (YMMV!), the auto-collimator is worthless on these scopes, as you must be very close to being on the money before you can tell which way to adjust the primary (and as a double-pass test instrument, it is subject to erroneaous indications that a defocused star isn't).

The final alignment should always be done using a point source (a medium bright star centered in the FOV using medium power is ideal)... see my notes for a quck/easy/accurate one-man collimation procedure using a defocused star.

Once set up, these scopes seldom need more than a minor tweaking.... like if they come crashing off roof-rack while negotiating a bumpy road or if its too heavy to carry out back so you simply tumble it end-over-end to get it to the mount! )

Paul

Paul