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hexalite706
23-08-2017, 11:08 AM
hello all
I am new to this forum
I have a Celestron Evo 8" SCT
for now only urban viewing

I purchased an amazing TV panoptic 27 (2")for deep sky viewing
Also have an Orion Planetary 9mm(1.25") EP

I wear glasses for astigmatism and Nearsightedness
Looking at maybe getting the 17mm TV Delos or the Nagler. the Nagler has a shorter eye relief of 17mm but better AFOV and is 2" so easier to switch with the Panoptic.
My questions are would the extra 3mm make a big difference for glasses??
Has anyone tried the DIOPTRX? Does it work well enough not to need to wear glasses?

Thanks in advance.

Wavytone
23-08-2017, 09:03 PM
Ahmed near (or long) sightedness is not a problem - focussing takes care of that.

Regarding your astigmatism, when looking at stars through the scope at low power, if you see nice dots its not a problem. If you're seeing stars stretching as lines or crosses you could use a dioptrix, they do work.

Its more of an issue at low power. At high magnification the exit pupil will be 1mm or less in which case its unlikely to matter.

Or do as I do - wear the specs most of the time regardless, and make sure you buy eyepieces with enough eye relief.