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Originally Posted by LewisM
I disagree to a point - I founf the Masuyamas wanting in reflectors, but fantastic in refractors.
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Eyepieces don't really care if you use them in refractor, reflector or catadioptric. All they care about is how fast is the incoming beam (f-ratio), how curved is the field and what off axis aberrations they are presented with. In some cases for example eyepiece's astigmatism can add to telescope's astigmatism (and off axis correction becomes really bad), in some rather special cases (like Jones-Bird and a Plossl) they will cancel and you can enjoy nearly perfect view, despite both scope and the eyepiece being decidedly
non perfect. But this is a rather unique scenario (as is now long gone Pretoria with its negative coma, targeting Newtonians). These days eyepiece designers try to make them as aberration free and as flat as possible (so their creations can be used equally in all different telescopes).
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I have the same opinion as yours though about Televue. Never used a single TV EP I found to be excellent - all were good, and merely that. None were exceptionally sharp - I found Vixen LV EP's better in terms of sharpness and disc size. As such, there is not a single TV EP in my tiny collection (Parks only now)
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You must be either much more critical observer than me or have access to some incredible optics. None of my telescopes measures significantly better than 1/35 wave RMS on the front (although my 12" gets close).
Both Type 5 and Type 6 Naglers as well as Ethos' add approx 1/35 wave to the telescope's wavefront (measured by French AiryLab), so telescope would have to be much better than that before we start to blame the eyepieces for any loss of sharpness. Not to mention that your eye too has to be capable of detecting wavefront residuals well into 1/50, or better yet, 1/100 wave.
If you really could see that much degradation to "disc size", my hat is off to you.
I just don't get obsessed with eyepieces. Larger scope or better mirror (or both) will always show more to any object even if used with vastly inferior eyepieces.
But I do understand very well that arguing eyepieces is much more emotional than analytical (it is hard to do objective assessment to something that you either like or not like). It is little bit like arguing audio cables - I keep saying to some of my mates that it will be much more of an improvement if they invested $$$ into better speakers rather than a piece of wire, but that advice invariably always falls to deaf ears. Even if I'm usually the one blamed as being deaf.
Or blind in this case
