Quote:
Originally Posted by Ross G
Would having the guidescope on the far right and not in the middle over the DEC axis affect the guiding?
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Only if balance, regidity or flexure are adversley affected. Providing the guide scope is moving with RA and Dec just as the cameras are, and that there is no flexure or balance issue, you can put the guide scope where ever you wish.
Quote:
Originally Posted by Ross G
This morning when I looked at the images, I noticed that the stars to the left of the frame were not as round as the stars to the right of the frame.This was visible on all the shots from both the 135mm lens and the 24mm lens.
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This can be caused by many things and often is something you just have to live with and might be able to rectify in post processing. Some possible causes:
- Atmospheric refraction. You are working with wide fields so it is easily possible the difference in altitude of some stars in your FOV will mean they appear to move at a suffciently different rate other than sidereal due to atmospheric refraction. You would find that even though a star guided on in one part of the FOV is circular stars in another part of the FOV might distort.
- Lens or mount of lens to camera that is not perfect. If something is not perfectly flat to the focal path then you might find stars are not perfect across the whole FOV
- Field curvature of the lens combined with atmospheric refraction. Often at wide fields of view these two can combine to make different corners or sides of the FOV have circular stars and other areas do not.
Quote:
Originally Posted by Ross G
Could this be a result of having the guidescope on the far right of the platform?
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I think it's unlikely. It's possible flexure and balance combined with field curvature could produce non-uniform stars, and balance and flexure could be affected by your chosen positioning of the cameras and guide scope. But specifically having the guide scope off-centre, that in its self shouldn't produce any adverse results.
Hope that helps.
Roger.