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Old 01-07-2012, 01:47 PM
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naskies (Dave)
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Join Date: Jul 2011
Location: Brisbane
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Quote:
Originally Posted by Honest_Gaza View Post
[*]Moving the Primary Mirror (seems a bit drastic)
I can get my Skywatcher flex tube Dob to focus simply by not extending the secondary mirror all the way, i.e. about an inch short of the normal visual position.

It's one (of several) reason why I went with a truss instead of solid tube version.

The downside of using a barlow/teleconverter is that the focal length may become too long for convenience. An APS-C (crop) sensor will just fit in the sun/moon at a focal length of ~ 1600 mm... so even with just a 2x extender you probably wouldn't be able to fit them in with a single shot.
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