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Old 05-05-2009, 10:23 AM
dpastern (Dave Pastern)
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dpastern is offline
 
Join Date: Jan 2009
Location: Brisbane
Posts: 2,874
It looks promising, but I'm still worried about the star elongation - you can see that on these shots:

http://3.bp.blogspot.com/_gXAjcr03u5...0-h/M13Web.jpg

http://3.bp.blogspot.com/_gXAjcr03u5...0-h/M82web.jpg

http://2.bp.blogspot.com/_gXAjcr03u5...b_filtered.jpg

that there is star elongation on the left, but not towards the right hand side of the frame. Or, on some of the stars, the elongation is in a different direction. Is this typical of field curvature? I would have thought the elongation would be in the same direction, or am I (probably) wrong?

I'm really curious to see these units with the focal reducer/field flattener in play and a solid focuser without slop. Oh, and properly collimated. I don't think the scopes I've seen have been perfectly collimated yet to be honest, although most have been very close I do admit.

Dave
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