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
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...
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...