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    Re: Extremely poor conditions, details.
    From: Marcel Tschudin
    Date: 2012 Mar 21, 15:57 +0200
    Alexandre E Eremenko, you wrote:
     
    I repeat: everything looked quite nice. The horizon looked crisp, except
    yes, crisp horizon
     
    the part under the Sun where there was glare.
    yes.

    There was only one somewhat strange thing that I noticed.
    There was a very strong glare on the water under the Sun, usual thing.
    So strong that it was uncomfortable to look at it without sunglasses.
    yes

    I had no sunglasses, but I tried to look. And what I saw, loked like a "bump"
    on the horizon under Sun. I thought that this must be some optical
    illusion caused by reaction of the eye on the glare ("irradiation" or whatever). Of course, the horizon filter
    filtered the glare, and there was no visible "bump" when looking through the sextant horizon glass with a filter.
     
    Yes, all this relates to a ducting phenomenon from an inversion which is typical in spring. The setting sun looks then like in the pictures shown here http://mintaka.sdsu.edu/GF/mirages/mirintro.html The "bump" or this line of light (in the last 3 photos) sticks at the horizon. It delays the moment of sunset compred to what one would expect from the sun's movement while its setting, thus indicating that sunlight is ducted. The sun is in such conditions indeed brighter. This is not only an impression. Photos with normal exposures for the setting sun become indeed overexposed.

    Marcel

       
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