Thread: MotoFocus
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Old 31-08-2015, 09:40 AM
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multiweb (Marc)
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Join Date: Oct 2007
Location: Sydney
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Quote:
Originally Posted by The_bluester View Post
Marc, how does the C11 do for image shift using an electronic focuser? There is always visible mirror shift with my C925 when I change focus.
Very minimal at F/10, non existent with the hyperstar. You usually get shift when you change focus direction but it's likely during the night the temperature will drop continuously during your imaging run. It's pretty rare to have wide fluctuations up and down in temperature.
Quote:
Originally Posted by The_bluester View Post
Does it have an impact or does it move focus slowly enough that with an OAG (Which will also see the image shift) the movement is guided out?
I've never checked if the OAG ever lost the guide star due to refocusing while imaging but I doubt it very much. At F/10 the star moves more due to seeing than any mirror shift.

Quote:
Originally Posted by The_bluester View Post
And what do you focus with, a guide cam after matching focus with the main imager?
I use a lodestar and PHD.
Quote:
Originally Posted by The_bluester View Post
I am not on that slippery slope yet (AP) but always keeping an eye on things for ideas.
Pic of rig set up at home below.
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