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pmrid
25-03-2011, 09:14 AM
Has anyone got any recent news on the supposed release of a FR from Celestron for EdgeHD scopes?
I have just spent the last of many nights testing a possible solution manufactured by Optec called the Lepus .62 reducer said to be suited to HD optics. Sadly, and despite some amazingly helpful co-operation from their CEO Jeff Dickerman, it seems that the Lepus re-introduces major off-axis coma no matter how careful you are about placement, spacings etc. Dickerman even sent me over a prototype for a modified mounting system for the Lepus as a last resort and a newly housed lens system. But it didn't work as it should and sadly, is on its way back to Optec.
I've been lent an AP telecompressor thanks to the generosity and patience of Gary Beale that I hope I can get enough sky to test tonight but it's a refractor design and I'm not expecting miracles.

So at the moment, I'm in the position where the sexy optics of the EdgeHD system are probably only good for visual use or for imaging at F11 until Celestron get their optical act together. I can swing my HyperStar back onto this scope but what a waste. I've reserved that to use with my plain-Jane C14 as soon as my PMX arrives.

Does anyone have any glimmer of hope to offer?

Peter

MikeyB
25-03-2011, 09:39 AM
A couple of the ideas in the below thread might be worth checking out if you haven't already seen it:

Hunting for a 2" ED, Apochromatic non-aspheric lens design focal reducer (http://www.iceinspace.com.au/forum/showthread.php?p=695343)

gregbradley
25-03-2011, 04:00 PM
The 2.7 inch AP I think its called the 67 reducer works on RCOS scopes.
But it is used by itself and no in conjunction with an RCOS flattener (I do not know if it would work with one but I doubt it).

Perhaps its worth asking on an Edge HD group if that would work.

In my experience flatteners and reducers do not work together. Perhaps they are trying to do 2 things that are not optically compatible.

The Edge HD is an SCT with a corrector (flattener) is that right?

So a compatible reducer may be tricky optically to make.

Probably not impossible. Planewave CDK has a flattener/corrector as part of its system and they market a reducer so perhaps it can be done.

Greg.

pmrid
27-03-2011, 08:37 AM
Thanks Greg. Check out the results of tests with the Lepus and the AstroPhysics CCD&67 in the thread "Good news for EdgeHD imagers".
Peter.

gregbradley
27-03-2011, 10:11 AM
That's great news. The bad news though is that it most likely won't work with a large chip camera, but fingers crossed.

Greg.