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    Bushnell Rangemaster: Vintage Binocular vs. Modern Birds

    Yes....that's the big one! I smuggled myself into the MIT/Barker Library once but I don't look like a grad student anymore. Maybe my town has a cooperative deal with UMass.
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    Bushnell Rangemaster: Vintage Binocular vs. Modern Birds

    It's been amazing watching the analysis of the Rangemaster and all the permutations. Reminds me a lot of the aircraft model histories I used to read. It's neat watching the lenses and mechanics drift through different models as they tweaked. There's a lot of Japanese binocular history that...
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    Bushnell Rangemaster: Vintage Binocular vs. Modern Birds

    I'm not sure the increase in absorbtion is in the intended range. I think it's unintended rays, stray light. If there are many coatings, the angular absorbtion would have a flattish rippled top, like a bandpass filter, and steep sides (vs angular rotation of the lens). We used such a coating in...
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    Bushnell Rangemaster: Vintage Binocular vs. Modern Birds

    I was down on amber coating for quite a while. Among other things, it seems to haze up more easily. I finally took a chance cleaning Sears Discoverer pair. The contrast became huge, and the brightness only came up a little. With old blue or the violet "UV" coatings, both come up a bit. I am...
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