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wide field ep for a 12.5" f/4.7

Started by moutinho, 05/04/2004 04:52PM
Posted 05/04/2004 04:52PM Opening Post
Hi,

I would like to have some advice on wide field ep for a 12.5" f/4.7 dob. Mainly at 19mm-25mm range. I do not have a 2" focuser !!

Thanks,
Andre
Posted 05/04/2004 05:10PM #1
Andre,
I can't think of a better option than the TeleVue 24 Panoptic. I use it in my Portaball (10" f/5) and it performs extremely well! Very crisp, good definition, and contrast. Edge is pretty good in the f/5. Nothing better that I could recommend, except maybe two of these in a binoviewer (and I know what THAT looks like too!).
Good luck,
-Curtis
Posted 05/04/2004 06:44PM #2
24 Panoptic. There, that's three unanimous votes. I have an irrational affection for this eyepiece.
Posted 05/04/2004 07:43PM #3
I'll go along with the crowd recommending the 24mm Pan. If you had a 2" focuser I would recommend the 22 Nagler. My reasoning is the 24mm Pan will give 62X at with an exit pupil of 5.1mm which is very comfortable for most of us and with optimal throughput for most of us as well. A larger ep with a longer focal length will give a wider FOV but at the expense of placing it in the pupil of your eye. If you had a 2" focuser a 22 Nagler would give you approximately 67X with an exit pupil of 4.6mm.

Perhaps an even better reason to switch to a 2" focuser is so that you can use a Paracorr with your scope. I have an F4.3 dob and would not consider being without one for use with my low power eps.

Randy

Randy Roy