Have heard rumors that the Pan. 41 performance was not suited for some particular scopes, so my question is; what major difference would one see in a side by side with the 31 Nag.? Other than a decrease in X and field of view. JM
John, When I checked out the 41mm Pan and the 31mm Nagler in a C-11 f/10 and a 14.5" SM F/4.3, the 31mm Nagler was the best for Coma, exit pupil (eye position) and over all performance in both scopes. The difference in image was not dramatic, but it was obvious.
To say "other than field of view and magnification" doesn't leave much left over. The Pan 41 is an under-rated eyepiece that lives in the shadow of the Nagler 31. Most people would get one or the other. Myself, I think that having an eyepiece which delivers the most fov you can get in your scope is worthwhile.
But of course one should possibly get both. Myself I prefer the XWs and have the 30XW and the 40XW and use them both extensively. The Pan 41 is very respectable. If the 40XW didn't exist I'd have the Pan 41.