Eyepieces - Less glass is more

[FaintFuzzies]

Other viewpoints? You came to the right place <g>. The differences among the various eyepieces that are easily seen in the 48" simply cannot be seen in my 25" or 30". I have a full set of UO volcano tops which rarely get used because, after extensive A/B comparisons with my Nagler T6 set, I can see no discernible difference in contrast, light grasp, or, for lack of a specific word, detectability of objects in my scopes. With all else equal, I prefer the wider apparent field.

Both Jimi and I do see the difference in his scope, and neither he nor I see the difference in my scopes. We have discussed this phenomenon ad infinitum, and a couple of years ago we asked James Mulherin for a professional opinion. His theory was that it's a matter of small percentage differences that yield a large enough absolute difference in the larger aperture to cross the threshold of detectabiity, while remaining unnoticeable in the smaller scopes.

On the other hand, at GSSP 2009, five observers, including Jimi and I saw the difference between the ZAO-II, UO HD and Ethos (all 6mm) in my 22". The UO HD is between the ZAO-II and Ethos, but a little closer to the ZAO-II in light transmission and the ability to perceive additional detail. Jimi and I agreed that the difference between the ZAO-II and the Ethos is obvious. Lastly, one of the five was a beginner and even he saw the difference.

One of the object we were looking at was the triple galaxy system, NGC 6745 in Lyra.