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Old 01-11-2011, 11:08 AM
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RickS (Rick)
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Join Date: Apr 2010
Location: Brisbane
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Quote:
Originally Posted by originaltrilogy View Post
So these have lens inside that bends the light before it gets to CCD instead of moving the mount for little fixes yes?
Does image degrade with extra glass in path?
It's a flat plate rather than a lens, but it does lose a small amount of light (claimed to be about 2% for the SX unit).

Quote:
Originally Posted by cventer View Post
Rick do mean back focus or inwards focus ? With the extension rings for the gso I am surprised back focus is an issue? I would have thou go inward focus travel may be with sx ao, plus filter wheel plus camera etc...
I mean that I don't have enough back focus distance on the RC10 to fit my intended imaging train (focuser, focal reducer, AO-LF, FW, camera) so, yes, this could also be described as not having enough inward focus travel. I'm currently using a Feathertouch focuser which chews up a lot of distance.

Cheers,
Rick.
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