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That we all see something different in eyepieces is brought home to me by your post, Alex.
For me, there is so much obnoxious coma in the 13mm T6 at f/5 that I immediately used it with a coma corrector to make it nearly perfect.
At f/4, I woudn't even try to see how it does without a coma corrector since I'd never use it without one at f/5.
And the 14mm SSW, to my eye, has so much spherical aberration of the exit pupil at f/5.75 (coma-corrected f/5) that I cannot even use it. That's an exit pupil of 2.43mm.
In my f/7 scope (exit pupil 2mm) it's still pretty bad.
Perhaps by f/15 (0.93mm exit pupil), that clears up. It's well known that larger exit pupil size makes SAEP less tolerable.
guess the difference in our observing styles is that I would not knowingly use any newtonian scope without a coma corrector, so, for me, I evaluate an eyepiece's performance based on how it works in a newtonian scope WITH a coma corrector. Coma, I can correct, but astigmatism I cannot, so if the eyepiece displays any astigmatism, it goes.
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