Pentax Orthoscopic 12mm

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Brand and Model:Pentax Orthoscopic 12mm
Price ($USD):Discontinued
Focal Length:12 mm
Barrel Size:0.965 in
Apparent FOV:42.0 degrees
Field Stop Dia.:0.0 mm
Eye Relief:9 mm
Weight (lbs):

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Pentax Orthoscopic 12mm
This is my favorite eyepiece for lunar observing. I'm always shocked to see the diverse colors of the lunar surface with this eyepiece. It is sharp as sharp can be. Too bad they're discontinued.

Overall Rating: 10
Weight: 1 (Unreliable Vote)
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Pentax Orthoscopic 12mm
Bright, rather well-corrected (if small) field. Not entirely happy in an f/5 cone,
where stars near the edge show a little astigmatism; better in slower cones. No ghost
reflections. Crisp lunar views.--
Noticeable yellow tint when pointing at the moon (even more so when it's sitting in a
2.5x Powermate which appears to use the same yellowish glass for one or two of its lenses).--
No longer made, I got mine second-hand. (Rarely have I signed a cheque so fast - none
other than Markus Ludes was standing next to me, wallet in hand; I'd been just lucky
to spot the little box a moment earlier!)--
I added an oval eyecup for stray light protection and very comfortable viewing.
Standard filters go into my (Vixen) 1.25"-0.965" adapter. This adds 16mm optical length,
which must be compensated by the focuser.

Overall Rating: 8
Weight: 1 (Unreliable Vote)
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