Quote:
Originally Posted by Moon
It depends on your definition of collimated. My definition is the stars on a full frame chip are symmetrical - and hopefully round. The view I see with my Catseye is not the endgame. It's the second last step. Final tweaking is still required after the Catseye is removed and the camera is inserted.
James
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Hi James,
IMO the Catseye autocollimator is capable of getting you much closer than "in the ballpark". I always check my collimation on a defocused star at high power (200X plus) after using the autocollimator and invariably my Tectron autocollimator has me almost spot on and I don't need to tweak anything. If I do need to tweak it, it is about 1 time in 5 and about 1/10th of a turn on 1 screw, which 95% of people wouldn't detect or wouldn't worry about anyway.
I think there are 4 possible problems causing the autocollimator to not be giving you the desired results. These are in order of probability IMO.
1) Your triangle or spot has not been correctly positioned on the primary
2) You have flexure in your focuser drawtube and housing, or play in the drawtube rollers, which manifests under the load of the camera.
3) Your focuser is not squared to the optical and mechanical axes of the telescope and the camera focuses in a significantly different focuser position to that which you are using the autocollimator.
4) The optical and mechanical centres of the primary mirror are not coincidental.
That all having been said you need to use a method that works for you with the equipment you have. However, that doesn't mean it is what the "majority" needs to do.
Cheers,
John B