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Message: <blockquote data-quote="henry link" data-source="post: 3345462" data-attributes="member: 6806">You might check out these adapters made by APM:<a href="http://www.apm-telescopes.de/en/eyepieces/eyepiece-accessories.html" target="_blank">http://www.apm-telescopes.de/en/eyepieces/eyepiece-accessories.html</a>I have an older APM 2" adapter made for Zeiss Diascope eyepieces. It can be used with other spotting scope eyepieces, including the Kowa 88/77 series, by simply substituting longer grub screws. APM can probably advise you as to whether either of their current Leica/Meopta adapters can be used with Kowa eyepieces. I tried the Kowa 25-60x zoom on my 92mm Astro-Physics Stowaway. I didn't like it as well as the Baader zoom I normally use. The deal breaker was much lower light transmission. It also has pretty strong barrel distortion. I didn't much like the distortion, but thought I would probably eventually adjust to it.I usually use the USAF 1951 chart of line pairs for resolution testing, but a few years ago I experimented with single line resolution, like a distant guy wire. I used a strand of my wife's very fine hair taped to a white card. I was amazed at how much easier it is to detect a single line than it is to separate line pairs, probably considerably more than an order of magnitude. It was so easy to detect the hair at 200' that I resorted to stopping down the scope to reduce its resolving power. Even at an aperture of 10mm the hair was still easily detectable at 200', so I gave up on single line resolution as a practical backyard test. It certainly shouldn't be compared to the resolution of line pairs or double stars.Henry</blockquote>

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