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Old 07-05-2014, 10:39 PM
Star Hunter
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Focal reducers: Which one for DSLR work?

I've got a C14 OTA F10 scope and want to know, what can I use to get the scope's ratio below F6.3 for imaging with a DSLR?

Would a Meade 3.3 reducer work using a Canon 7D, 60Da for instance?

I've also gota 12" F15 C/cassegrain and that too, requires a f/reducer. Any suggestions on what would work?

Jim
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Old 12-05-2014, 08:57 AM
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blink138 (Pat)
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from what i have read the f3.3 reducer will not work as it is only successful on much smaller chips, something to do with the steepness of the entering light cone i think
i use an f6.3 reducer on my c11 and that works extremely well
if you want a true widefield from your bucket you need to do hyperstar imaging at f2, there is a lot of info on this on the net and a few of our members are involved in this type of imaging
regards
pat
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Old 13-05-2014, 01:15 PM
Star Hunter
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Thanks Pat for your reply. I concur re the 3.3 reducer. Unfortunately the white C14 OTA is not a fastar design. That scope came out in the early 90's and the black OTA fastar I already have, came out in the late 90's.

So I'll be using this white C14 scope with the F6.3 reducer as this will at least, give me some respite from F10.

I will piggy back the soon to arrive, Sky Watcher BD 180 Mak as a guider at F12 and another use an F6.3 reducer for imaging. I just have to get a 10:1 motor focuser for that scope. I think JMI has them to suit the Mak's back flange.

Jim
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Old 13-05-2014, 02:15 PM
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blink138 (Pat)
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good luck then jim
by the way you may get an awful lot of flexure between the 14 and a large mak on its back for guiding
there was a recent thread on here last week on a very similar combo i think
pat
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Old 13-05-2014, 07:28 PM
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Yep OAG needed instead of a guide scope Jim. You will need lock down bolts too to prevent that mirror from moving around (if you have not done that already).
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