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2" vs 1.25" eyepieces

Started by HowardP, 05/15/2004 01:37PM
Posted 05/15/2004 01:37PM Opening Post
I understand that 2" eyepieces have a larger field stop and let more light pass thru to the eye resulting in larger TFOV and brighter images.

What about the 1.25/2" skirted eye pieces? Aside from the convenience of not having to change the adapter at the diagonal ... does more light get thru than a 1.25". Is there any other advantage?

For example the Nagler 16, 12, and 9 mm pieces.

Thanks in advance howard
Posted 05/15/2004 09:04PM #1
So it does make sense to buy long focal length (low power) 2" eyepieces to get a truly large TFOV, if that is the goal. But to get the 2" pieces with the shorter focal length (higher power), does not seam to make sense as there is no real optical value?

thanks howard
Posted 07/02/2004 08:44AM #2
"What about the 1.25/2" skirted eye pieces?"

THese are 1.25 inch eyepieces with a convenient permanently mounted 2" adapter. The manufacturer could have put them in a 1.25 barrel only and not changed anything optically.