Celestron f/6.3 focal reducer corrector

[Astro_Dad]

Interested in experience here of using the above reducer/corrector with a Celestron C6 for visual use.  I tried last night with a newly acquired second hand unit. The reducer clearly increased the true field of view and provided a higher exit pupil (and hence brighter image) using a range of Plossls up to 32 mm, and BST Starguiders in the 12-18mm range.  All more than satisfactory on deep sky, with very sharp images achieved (I did notice the C6 needs a little collimation following a quick star test however), but on Jupiter I noticed obvious rings or arcs of light all around the target - Jupiter itself was a sharp as could be expected given the average to poor seeing conditions, but curious as to whether this type of aberration  around the edges of a bright target is typical - I’m aware of the optical limitations of using a focal reducer/corrector for visual use in general  - particularly linked to edge distortion on longer focal length eyepieces etc. But didn’t expect this light effect on bright planets. Any thoughts? Could this be due to a need to collimate? 
Thanks, AD

[ollypenrice]

I don't recall seeing this but I switched to a 2 inch back and long FL EPs in order to get the widest FOV. (The reducer doesn't make the view any wider if you do.) Then again, would you want to use the reducer on the planets?  More glass is always an invitation to more reflections...

Olly

[Ags]

With my C6, I have used the 6.3 reducer on planets, mostly due to laziness. I didn't see any reflections introduced by the reducer, which seemed to improve the overall image quality somehow. The C6 has internal reflections of its own - arc-like ones you can see when Jupiter off axis. I think that's due to the unflocked internals.

[Louis D]

Try to characterize the aberrations more by moving Jupiter around the field of view (edge to edge as a start) to see how they appear to change.  Also, try different eyepieces to see if the effects change.  Of course, repeat all this without the R/C.  You're likely seeing internal reflections from the baffle tubes, rear port, visual back, and/or the reducer or eyepiece.

[Astro_Dad]

Thanks for comments and suggestions - I’ll investigate further and determine where a real issue or not. I don’t recall seeing these reflections without the reducer, but will need to check again. As has been mentioned, not a major issue as the reducer not needed for planetary anyway - but convenient to keep permanently in place.