Re: Color contrast at the night sky?

Hinnark wrote:
Hello,

I found some interesting discussions within this forum and thought this
could be the right place to ask for opinions or ideas about some
observations I made last year with a couple of 7x42 and 8x32 binoculars
at the night sky. In fact I have some trouble to understand about what
I saw last but not least because it seems to be in conflict with some
old doctrines about visual perception. Well, to make a long story short
here are my findings. The binoculars that had the best color contrast
in daylight showed most detail in DSO nebulas like for example M33, one
of my favorite objects for investigations of a small instrument´s
contrast performance. That was NOT the case when watching at
terrestrial objects. Here perfomed those binoculars best that showed
best contrast in twilight. These binoculars use to have a slightly
yellow color cast. These finding were made not only by me but with some
friends who came to same results. Doctrine says that at night in the
dark only the rods work in our eyes and those are sensible only to grey
tones of light. So if my observations are correct - and I´m pretty
sure they are this means that the cones aren´t really out-of-work at
least under the 5.0 - 5.7 mag sky we came to these findings. What do
you think?

Steve



Several years ago, when observing, out in the country, I remember
realizing that the sky was blue and not black. My eyes were fully
dark adapted! The sky was glowing blue--There was a pretty good
auroral display going on--which I hadn't noticed for sometime due
to buildings and trees to my north.

The ionosphere was alive--reacting to the outpouring from our sun.
no matter what magnification I used, the background was blue.

-Sam


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Relevant Pages

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