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Moonlite Focuser and ONAG on a Edge HD9.25 - is that possible?

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#1 aacc66

aacc66

    Apollo

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Posted 04 April 2020 - 03:11 PM

Is it possible to get a full frame ONAG behind my celestron Edge HD9.25, and a moonlite focuser CHL 2.5?

I think not, but maybe I am missing something here.

 

The Focuser is 2.75" or 69.85 mm

The ONAG distance (OIBF) is 66mm for the SC and 68 mm for the XM

 

That adds for ONAG sc  --> 135.85, which leave only 10.65mm.  a mirrorless flange distance is 18 mm or a deficit of  7.35 mm

 

That adds for ONAG xm  --> 137.85, which leave only 8.65mm.  a mirrorless flange distance is 18 mm or a deficit of  9.35 mm (BTW: I own a full frame camera)

 

And this doesn't take in account adapters between focuser and ONAG and ONAG and camera.

 

Is this correct or I am missing something here?

 

I think I need to explain the main motivation for the question: I am using a celestron OAG, this gives me freedom of rotating the OAG to find a guiding star, but the way is designed, is not conducive for repeatable rotational placement if your imaging the same target across multiple weekends.

 

I got another adapter for the other side of the OAG and that will return back about 12 to 13 mm to place a couple of rotators (I will take something manual and it doesn't need to be automatic) if available but probably they need to be thin to go at both sides.

 

When not seeing a practical way to get the rotatos, I though, maybe it is time to get an ONAG, but it doesn't fit in there.

 

BTW: I saw Frank (freestar8n) placing setting angles in paper and attaching them to an older rig.  The main thing here is that the geometries are not conducive to attach paper marked setting angles (http://www.astrogeek...CGEOAGSetup.jpg) - I like the idea but the geometries do not help.  However, if someone has a way to mark the parts and make them visible at night I will not be opposed.

 

Any suggestions will be welcome.

 

Alvaro




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