Thread: Gso rc10
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Old 13-12-2011, 09:03 PM
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JohnH
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Join Date: Feb 2005
Location: NSW
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RC10 and FR

Thanks Rick,

I only have a small format ccd and 1.25" filters - so the 2.7" FR would be overkill and also mean I would have to go for a feathertouch or similar 2.7" or bigger focuser - which more cost than I can take for now.

If I have my calculations right the CCDT67 will still be useable with the AO-8 in line but it will give less than a .67 reduction as the separation will be > 100mm, a good rather than bad from a coverage pov. I believe total back focus will not be an issue as I intend on purchasing the new Moonlite 2.5" CFL unit that has just been released - this allows the FR to be fitted inside the draw tube and separation finely adjusted - pretty good I think.

The only item I need to decide on now is the tube - I was going for CF but as I am going to go for a motorised focuser it would seem I may as well stick to Al, are there any other reasons than cosmentic to stick with the CF tube eg total weight, better rigidity/thermal stability?

Finally is there any need to worry about dewing with these units and, if yes, how do you deal with it - dew shield? heaters (if yes where)?
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