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Originally Posted by OneOfOne
The Panoptic looks a little orphaned, maybe I should swap it for an XW-20?
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No!!!!! The 20mm Pentax XW is the worst of all the 1.25" Pentax XW series.
FWIW, I own the 5mm,7mm,10mm,14mm and 20mm Pentax XW's and 27mm TV Panoptic. I never use the 20mm Pentax XW. This has more to do with it's focal length than it's optical performance. Don't get me wrong it is still a very good eyepiece. On axis light transmission, sharpness and contrast are better than anything else available, but it suffers some field curvature from about 60% off axis. This field curvature is not so pronounced when used in a longer F-Ratio refractor, where the eyepiece performs very well. For instance it will work very well in Rocket Boys TOA-130. It won't work so well in a scope with an inherently curved focal plane like an 8"/f6 newtonian or a SCT.
Owning the 20mm Pentax XW and having used the 21mm Denkmeier I can tell you the Denk is a better eyepiece for similar money. I will be selling the 20mm Pentax XW and buying the 21mm Denkmeier when my Texan friend returns from the USA in a few months time.
CS-John B