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Message: <blockquote data-quote="elkcub" data-source="post: 1380042" data-attributes="member: 14473">It seems to me that ronh makes a valid point with regard to analyzing the color content of the pixelated photos.  This is different from analyzing the light emerging from the instrument's exit pupil, which would require a spectrometer.  But, if one is going to make such digital recordings in the first place, it's probably a good basis for making an objective comparison; rather than relying on individual color perceptions that are influenced by biological factors, color contrast, and the color bias of the monitor.  Using Adobe ImageReady for a quick evaluation, the RGB color mix of each panel is shown in the attachment.  Weightings vary somewhat over each area, but the main result is clear. (I'm too lazy to take an average of several readings, so I picked the center.)  The background is slightly weighted towards blue, and brighter than any of the four panels.  The average of the three RGB background values is 223, suggesting that exposure was 223/255 = 87.45% of maximum, — since on this scale pure white = 255 and pure black = 0.On individual panels, the Zeiss 8x50 image is biased green-red, the Nikon E image is biased red-green, the Zeiss FL image is almost neutral but slightly green, and the SE image is neutral.  These results represent the binoculars' filtering of the blue-biased background image.By expressing the average of the three RGB values as a percentage of the average background value (i.e., 223), the transmission efficiency of the four binoculars can be estimated as:Zeiss 8x50 = 172/223    = 77.1%Nikon 8x30 = 162/223   = 72.6%Zeiss 8x56 = 214/223    = 96.0%Nikon 8x32 = 213/223   = 95.5%This seems more or less reasonable to me.  The reliability of the procedure can be determined by others doing the same thing with their Adobe or similar software.  Ed</blockquote>

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