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Old 07-02-2012, 11:37 PM
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Tandum (Robin)
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Join Date: Apr 2008
Location: Wynnum West, Brisbane.
Posts: 4,166
Quote:
Originally Posted by Peter.M View Post
I found that guiding had alot of flexture involved, the futher your focuser is away from the guidescope the greater the problem as the steel tube flexes signifigantly.
I believe you'll find the tube is distorting around the focuser. Moon (James) found the same issue on the 8" and 12" steel tubes so I imagine the 10" will be the same, see here. You have to solve this problem or your collimation will be unstable and shift with altitude. I believe you are mistaking this for flex, no brand of OAG will fix this issue. I recently had a similar issue with a prostar tube and found putting a separate ring around the tube next to the focuser appeared to fix it but the scope went back to it's owner before I'd finished testing. If you dig up some pics of Mikes 12" newt you'll see an extra pair of rings, one each side of the focuser assembly.

Here's a pic of Mike focuser.

Last edited by Tandum; 09-02-2012 at 03:44 AM.
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