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Easier way to collimate my Meade SC

Started by wyliecoyote, 01/11/2003 04:12PM
Posted 01/11/2003 04:12PM Opening Post
The "experts", writing in articles and on the net, and the telescope manufacturers themselves, tell us to collimate using a slightly defocused star..the two diffraction rings scenario. This is difficult and thus in my opinion, absolute crap! Even so, most people hardly bother to go this far, collimating instead while looking at the 'big donut'at low power and are happy with "just about or good enough" collimation. With miserable results.
Don't collimate on a star at all! Why not? Well at 500-600x what do you see?..even with relative steady air the defocused highly magnified star will still be wobbling and the diffraction rings will be wiggling all over hell and back...how accurate a measurement can you do with this scenario??
Instead, try this...thread on a straight thru visual back adapter..don't use the diagonal..center Jupiter in the field of view..now you have a rock solid steady object to look at!..big difference..it's also bright and easy to see, large in the field of view...start at about 300x..look at the limb of Jupiter, usually one side will have a halo. That halo is a secondary image of the planet caused by miscollimation, & if your seeing that, your NOT getting NEAR the view your instrument is capable of, your not getting the most out of your SC telescope...go to the front of the scope and tweak the screws until that halo disappears..completely..now kick it, the magnification up, to 600x..say 4.6 mm eyepiece 2xbarlow combo...very very fine movements/changes now..1/15th turn..when your finished there should be no evidence whatsoever of limb halo, you should be looking at a solid planetary edge, while checking at high power all the way around the planet!..and I will guarantee you your eyes aren't going to believe the difference..when it's right on...WOW..POP..all those fine details you thought were impossible to get, with an SC, are going to suddenly be there.
Posted 01/12/2003 07:34PM #1
When your done doing your best with Jupiter, try a slightly defocused bright star like Rigel. A friend collimated his SC using a Xmas tree ornament!
Posted 01/13/2003 04:51AM #2
Wonderful advise! Makes me want to go out and buy a S-C just to try it! Bravo! I still use a film can to collimate my XT-8, great views at 250-300x. The best collimation technique is the one that works for you, Refined over and over! Chris Brown

There's something on the Moon! 8O
Posted 01/16/2003 05:48AM #3
Interesting way to collimate... got a give it a try.

What if there are two halos, one blue on one side of the limb one red on the opposite side? Which side do you move to?

Even with one halo, assume on the right side (90 degree position) and assuming your above setup, do you tighten or loosen the screw on the same side of the halo or loosen it to get better collimation?