Quote:
Originally Posted by Moon
There is also lots of info on the internets but the majority applies to collimation for visual, which is quite a different process, and has different objective.
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Hi James,
Why do things become different for imaging and visual purposes?
Collimation of a newtonian reflector focuses solely on aligning the optical axis of the telescope. If you wish to take collimation to the ultimate level, it also involves making the mechanical axis of the telescope coincidental with the optical axis. Making the optical and mechanical axes of the telescope coincidental does not affect optical performance in any way. It affects the pointing accuracy of an DSC system employed and the ongoing tracking accuracy of the telescope only.
Quote:
Originally Posted by Moon
You might get lucky and the collimation with the laser or cheshire is still ok when you put your camera in, but this would be good luck.
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A laser in itself is not adequate for collimating a telescope properly. A laser is only suitable for adjusting the "tilt" of the primary mirror, after the secondary mirror has been correctly positioned in the telescope and its axial rotation properly adjusted.
Quote:
Originally Posted by Moon
Tools will get you in the ballpark after you rip the scope apart and put it back together.
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This is not correct. Someone who knows how to collimate a telescope properly can collimate a telescope with a very high degree of accuracy using high quality collimation tools like the Catseye or Tectron Tools. Both of those collimation sets include an "Autocollimator" which is very accurate indeed. The only time these tools will not be 100% accurate is when the mechanical centre of the primary mirror (where the dot is) is not in fact coincidental with the optical centre of the primary mirror. Due to modern mirror production techniques this is a pretty rare occurence these days.
Cheers,
John B