I think you've hit upon the "problem" exactly! The Pentax, IMO, compares favorably with the Schneider 4X ASPH.
shel Rob Studdert wrote: > It does have pin cushion distortion however if you always view from the centre > of the loupe and move it over the subject then it's of no consequence. If you > leave the loupe stationary and expect to be able to see the media clearly by > moving your eye around the view aperture then forget it. I think the problem is > that most loupes suffer this problem however the view aperture of this one is > so large it tempts the user to use it inappropriately. Hence the often negative > comments, most of which you will find were gleamed whilst using one for 30 > seconds in a photo shop. I have both the Schneider 4x ASPH and the Pentax 5.5 > and I prefer the Pentax, it has no image quality problems.
