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Old 15-12-2009, 07:32 PM
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pmrid (Peter)
Ageing badly.

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Join Date: May 2008
Location: Cloudy, light-polluted Bribie Is.
Posts: 3,757
Quote:
Originally Posted by AlexN View Post
Peter - Nobody sells Astrotech in Australia, however OPT in the USA have very reliable and relatively cheap postage to Aus..

The GSO 8" RC and the AT8RC are the same scope, and that will flatten your field and reduce you to F/6 at the same time..

As for whats not to like... Well.. I wouldnt spend the money on the 8" F/8 RC for high resolution, then reduce the resolution by 1/4 for the sake of speeding it up to F/6. If I wanted an 8" F/6 I'd spend 1/4 the money and buy an 8" F/6 newtonian. Optical quality would be similar if not the same...

F/6 would give you about 1218mm F/L or there abouts, which would be similar to your 5" APO.. at that point you're starting to negate the reason for having both? You know what I mean?

The Astrotech 2" flattener (designed for refractors) has proven to flatten the field of the 8" RC well, without reducing the focal ratio... Thats what I would be doing in your shoes, but, everyone is different...
Hmmm! Good comments. Helpful too. Thanks.
Peter
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