Baader 36mm Aspheric with Focal Reducer on CPC 1100

[beka]

Some time back I purchase the Baader Planetarium 36mm Aspheric eyepiece and 2" clicklock diagonal to get wider views on my CPC 1100. The Celestron Omni 40mm eyepiece that came with the telescope has an apparent field of view of 43 degrees giving me a true view of about 0.6 degrees - with a f6.3 focal reducer almost 1 full degree. The Baader with its 72 degree apparent field of view gives a true view of about 0.9 degrees therefor not much gained. I therefore needed to use the Baader with the focal reducer. This was a problem because the Clicklock diagonal has a 2" barrel that fits into the 2" Clicklock visual back. After some searching I found this http://agenaastro.com/gso-sct-barrel.html product (I was happy that Agena ship to Ethiopia) that allowed me to screw the diagonal to the f6.3 reducer and the standard SCT visual back.  This combination gave me a true field of almost 1.5 degrees. However when testing the setup on some objects, I observed that stars were distorted (looking like little arcs) over the outer 1/3rd or so of the view.  Thus, although I have seen some users suggest using the f6.3 for visual, I would not recommend using it with the Baader Aspheric. I like the Aspheric on it own without the reducer though - I especially liked the view of Omega Centauri on one night, which stayed in my mind for several days!

[michael.h.f.wilkinson]

The focal reducer does not add more true field of view to the focal plane of the scope. It just compresses the 47mm image circle of a 2" barrel into 28mm of a 1.25" barrel. This is why you get severe vignetting, and other defects at the edge of the field when combining 2" EPs with these focal reducers. Distortion of stars at the edge can also be caused by incorrect spacing between the field stop of the EP and the reducer

[beka]

Well, you do get a larger true field of view (apparent field of view divided by magnification) - just distorted I guess...

[alan potts]

I have a SC scope that is similar in many ways to your own but slightly larger. I thought years back that plug in a reducer bang in a 40mm 2 inch eyepiece and I would be able to see my feet, how wrong I was. I found that the largest you can go with 2 inch eyepieces and have a sharp and clean field was the 28mm Meade 5000 68 degree eyepiece which gives almost the exact same FOV as the 40mm without the reducer but at a different magnification.

I did write a piece on this at length which is buried somewhere in equipment reviews. I also tried a 24mm Meade 82 degree eyepiece with reducer and that worked but the 26mm Nagler did not as it vignettes somewhat. Now I do not bother but use a 41mm Panoptic and I am not even sure where the reduce is now.

Alan