The 24mm Panoptic has zero barrel distortion (negative rectilinear distortion).
It does, however, have a lot of pincushion distortion (positive rectilinear distortion).
Total distortion is around + 5.5%. This is because of vanishingly low angular magnification distortion.
The APM UFF 24mm is another possible, with -0.27% distortion (a very tiny amount of barrel distortion). With such low rectilinear distortion, however,
it does have noticeable angular magnification distortion you can see when panning.
Another possibility is the 24mm 68° Explore Scientific, with +4.7%, slightly less than the Panoptic. It gets good reviews.
The Baader 31 should not be considered a 1.25" eyepiece, regardless of the adapter they come with.
It introduces quite serious and obtrusive vignetting.
Don thanks so much for the insight. I have been exploring what has been shared on this thread as well as this thread from 2017:
Lots of good discussion now and over the years. The quality of the 24mm Panoptic for tack sharp to the edge performance is what one gets for the premium price. Here are some factors with my own situation that figure in to the decision I will eventually make:
- My eyepiece collection is a diverse set acquired over 56 years. Except for a set of cheap Celestron Plossls no two of my most used eyepieces are of the same manufacturer or design. There are among these a Brandon, military surplus Erfle, University Optics Konig, MaxView-40, Olivion 58°, Plossl, Explore Scientific 100° and a TeleVue 11mm Nagler T6.
- While I am quite tolerant of less than perfect performance, particularly on the edge, my most used eyepiece on all different types of telescopes is the Nagler.
- While I wear glasses or contact lenses when at the telescope the glasses are not needed.
So with this as background and with the kind advice given in this thread and others I've narrowed my choices down to these:
From what I have gathered the two less expensive ones may not have the same extreme edge performance of the Panoptic. But $100+ may be a high price for that improvement. Yet my experience with the Nagler tells me I'll get what I pay for with the Panoptic. The advantage of the two others is there will be some extra money available for other useful accessories. I need to get another (expensive) Losmandy counterweight to replace the "pieces of junk" hanging on the G-11's counterweight shaft:
The "pieces of junk" mentioned are the black front crankshaft pulley off a 1956 Ford V8 and green drill-press vise. The latter has been replaced by an even less photogenic trailer tow ball/hitch. But without the extra funds available for a nicer looking counterweight, I can get by with the junk at hand.
Back on topic I would really appreciate more real world reports on the performance of the APM UFF eyepiece. I'm not familiar with that brand or its offerings. Can any of you help in this regard?
I note the APM eyepiece is much larger and significantly heavier (8 oz versus ~12 oz). I used Google translate on this report:
APM 24 vs 24 Panoptic - The pictures tell the story regarding size.
Getting the APM would not only save money, but enable adding the 9th or 10th different design/manufacturer to my set.
I just need to know how it is rated by others. I'm getting close to ordering my new 1-1/4 inch wide field eyepiece.
All the Best,
Edited by Rustler46, 25 November 2019 - 02:39 AM.