Re: ATM Draw tube into lightpath

[Brian Nestel <blast@aloha.net>]

Jan Saver wrote:
> What would happen if a 2 " drawtube would be placed about 1" into the
> lightpath of a 10" newtonian ?
Hi:
Since in your other message you asked about a lumicon low profile
nonrotating focuser, I'll base the answer in that. With drawtube
fully racked in the draw extends 1" beyond the focuser base into 
the OTA less the OTA wall thickness, so if the wall thickness of
the OTA is 1/4" the drawtube extends into the OTA 3/4" which if
your OTA is 12"ID, the proper size for a 10" mirror, shouldn't be
in your main light path 
-- 
Aloha   159 36 W, 21 58 45 N
Brian   Middle of the Pacific,
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