8.5 Pentax XF

Thinking of trying one of these out...any of the folk here had experience with one of these? I picked up a 12 mm XF and liked it. Has some field curvature going on, but since I use that mag range for galaxies in a 14" dob, it hasn't been a problem for me. If the 8.5 works similarly, that wouldn't be a problem either. Thanks for any thoughts you may have to offer!
Larry

For me the 8.5XF was flatter than the 12XF. Other than that it was the same except for one, unfortunate detail. Unlike the 12XF, the field group baffling of the 8.5XF wasn't very good, and while both 12 and 8.5 lack edge blackening of the field group, it stuck out like a sore thumb with lunar observation on the 8.5 because the baffling wasn't as good. It wasn't a problem for me with my eye properly positioned, but if I backed off just a little bit, my eye was flooded with glare from the lit up edge of the field group. They actually warn you about this in the papers that come with the eyepiece. Of course they say it's no problem, really, but for me, I'll be the judge. If I hadn't wanted the eyepiece for lunar observing, I wouldn't have cared, but in fact I did, and I did.
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Mike