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Edge HD 800 Back Focus Issues!

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#1 NeoZavier

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Posted 25 August 2013 - 09:51 AM

I recently bought the Edge 8 .7x Reducer lens and the Celestron new off axis guider and using the off axis at F/7 I cant focus both! But at F/10 I don't have a problem. It appears that the back focus of the telescope at f/10 133mm but with the reducer lens is just 105mm and I cant focus My Nikon D90 and the orion starshoot auto guider. Has anyone bean able to go around this??? H.ow can celestron do this *BLEEP* reducer and the 11 and 14 don't have this problem they maintain back focus with reducer. :mad:

#2 tecmage

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Posted 25 August 2013 - 06:50 PM

Post deleted by tecmage

#3 tecmage

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Posted 25 August 2013 - 10:46 PM

:jump: :jump: :jump:

#4 frebie

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Posted 26 August 2013 - 11:36 AM

When talking with Celestron about using their new off-axis guider (not the Orion StarShoot OAG, which may have different spacing requirements), with their various EdgeHD reducers, Celestron acknowledged that the one combination that does not work out of the box with their OAG would be the EdgeHD 800 +0.7x Reducer + DSLR. None of the adapters included with the OAG add up to the exact 105mm back focus distance required. Celestron feels there should be enough space to use their OAG (but no guarantees with the Orion) if a low profile 2” SCT back is used with a 2” to T-thread nosepiece instead of the long Celestron 8” EdgeHD T-adapter. The Edge T-adapter has to be long enough to accommodate the focus and mirror lock clutch knobs when used without the reducer, but that makes it too long to fit an OAG into the light path.

Celestron will be adding a knowledge base article to their site about this.

#5 NeoZavier

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Posted 26 August 2013 - 12:19 PM

The weird thing is that if you put reducer OAG dslr is over 105mm correct me if I am wrong.

#6 frebie

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Posted 26 August 2013 - 02:56 PM

It is over 105mm, but that's why I pointed out in my post that "Celestron feels there should be enough space to use their OAG (but no guarantees with the Orion) if a low profile 2” SCT back is used with a 2” to T-thread nosepiece instead of the long Celestron 8” EdgeHD T-adapter."

You can contact Celestron customer service for further clarification.

#7 NeoZavier

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Posted 26 August 2013 - 05:22 PM

Ok thanks! I will contact celestron






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