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Planetary eyepieces and AFOV

Started by HowardP, 05/16/2004 09:55PM
Posted 05/16/2004 09:55PM Opening Post
TMB AFOV = 30 degrees
AP AFOV = 42 degrees
Pentax XO AFOV = 44 degrees

Any suggestions for larger AFOV in simillar design?

The radians are 60 degrees but have many elements.

thanks howard
Posted 05/16/2004 10:28PM #1
Wide field & few elements = poor edge of field performance.

At least, I don't know of any exceptions to this rule. Alas, there's no perfect eyepiece.
Posted 05/17/2004 06:25AM #2
I have a few TMB Mono's and a couple of Type 6 Naglers. The Mono's are definitely better, but the Naglers are as good as anything else I've used (Plossls, UO Orthos) but also more expensive. To be perfectly honest, all of the four mentioned are very good, and then there are Ultimas and Taks etc.. And, they are probably very good as well. To anticipate Alan French, "The differences tend to be subtle."