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IMAGING WITH C11-CORRECTOR SUGGESTION

Celestron C11 Reducer Flattener
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Filippo Bonfante avatar
Filippo Bonfante avatar
Hello everyone,
i still dont know which correctore/reducer i should use.
ATM i have a beautiful modified C11 with primary mirror block to avoid mirror shift so i just bought an ioptron iafs electronic focuser.
i have a celestron OAG and Player one poseidon m with filter wheel.
i dont have enough backfocus touse the starizona 0.7 sct corrector.

sooo    C11—ioptron iafs focuser—?corrector/reducer?—oag—-filterwheel and camera

with this configuration i have the space to have enought backfocus

any suggestion for a good one?
ty in advance
Tony Gondola avatar
Tony Gondola avatar
Is it the mirror block that prevents you from changing the focus position?
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Ashraf AbuSara avatar
Ashraf AbuSara avatar
Ideally the corrector / reducer needs to be mounted on the scope before the focuser, because the farther out your reducer is from the back of the scope, the less "reduction" you will actually achieve. 

I was not aware of that iOptron focuser. Is it a test unit? I used a Baader diamond steeltrack focuser with EAF on the back of the corrector, and that was short enough to achieve focus and have enough backfocus using the Starizona LF reducer/ corrector.
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Filippo Bonfante avatar
Filippo Bonfante avatar
Ashraf AbuSara:
Ideally the corrector / reducer needs to be mounted on the scope before the focuser, because the farther out your reducer is from the back of the scope, the less "reduction" you will actually achieve. 

I was not aware of that iOptron focuser. Is it a test unit? I used a Baader diamond steeltrack focuser with EAF on the back of the corrector, and that was short enough to achieve focus and have enough backfocus using the Starizona LF reducer/ corrector.

ty for the anwer
the iptro will arrive only next week.is designed to avoid z axis distortion using eaf for example...
so your configuration is

C11---STARIZONA---STEELTRACKWITHEAF----OAG----FILTERWHEEL/CAMERA
right??
ty
Tony Gondola avatar
Tony Gondola avatar
Ashraf AbuSara:
Ideally the corrector / reducer needs to be mounted on the scope before the focuser, because the farther out your reducer is from the back of the scope, the less "reduction" you will actually achieve.


I get that but is there a reason why you can't move the focal plane by slightly changing the primary to secondary spacing as you would in a traditionally focused SCT? Even if it changes the reduction It would be worthwhile to get everything to work, at least until you can find a better solution.
Filippo Bonfante avatar
Filippo Bonfante avatar
Tony Gondola:
Is it the mirror block that prevents you from changing the focus position?

Hello!
yes! the problem occurs during meridian flip as far as i know
Tony Gondola avatar
Tony Gondola avatar
I get that, what I was asking is can you adjust the locked position of the primary to push the focal plane outward, then re-lock the primary?
Filippo Bonfante avatar
Filippo Bonfante avatar
still dont know…i havent tried yet…i think i'm gonna find a near focus with primary then block it and fine focus with electronic focuser