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Message: <blockquote data-quote="Surveyor" data-source="post: 1390424" data-attributes="member: 50720">Henry, I first tried to get a feeling of color shift just by visual appearance as you requested. My estimates for Slide 2 were that the shift from the background of the two left swatches either were down in transmission or had a shift towards the red end of the spectrum and since I knew the characteristics of the two binos, I estimated a shift towards red but could not tell how much. Looking at the top right swatch, I estimated a shift from the background in the blue-green direction; I was able to cheat a little here since I know all these models are within a few percent of each other in transmission. The bottom right swatch I estimated as having less transmission and a greater shift in the red direction than the two left swatches. Then I went back through them, measuring the RGB values as previously described with the following results:  Background average of 8 samples=227.5,229.375,231.5Leica 8x42 Ultravid value=215,215,215 and shift=241,239,237Swarovski 8.5x42 EL value=215,215,215 and shift=241,239,237Zeiss 7x42 FL value=215,219,218 and shift=241,243,240Nikon 8x42 LXL value=212,213,208 and shift=238,237,229 This leads to the following estimates of transmission and color shift: Leica 8x42 Ultravid = transmission 95%, shift 30 degree, S=2 (orange)Swarovski 8.5x42 EL = transmission 95%, shift 30 degree, S=2 (orange)Zeiss 7x42 FL value= transmission 96%, shift 100 degree, S=1(light green)Nikon 8x42 LXL value= transmission 94%, shift 53 degree, S=4(orange-yellow) Note that the saturation number may end up being analogous to value of intensity along the dominant wavelength in CIE colormetry i.e. the Zeiss only shift 1% in the light green direction, while the Nikons shift 4% in the orange-yellow direction. This is only a thought and needs further investigation. Henry, you might clarify one point. My colormetry work starts with a known value and mathematically arrives at the native color point of the bino. I am assuming that you intend to estimate the shift from whatever background is present, instead of a fixed value. I went towards the shift perspective since it looks as if it matches most perceptions better. Now on to Slide 3. Visual inspection leads me to think there is a color shift of either orange or yellow from the background with a small transmission loss in the bottom swatch compared to the top (more about this later).  The measured parameters were:Background average = 228,228,232.5Zeiss 7x42 FL value = 219,221,218 and shift =245,247,239Zeiss 8x32 FL value = 213,215,212 and shift = 238,240,233 Resulting in: Zeiss 7x42 FL transmission (Luminance) 97.1% shift 75 deg. S=3% (yellow-green)Zeiss 8x32 FL transmission (Luminance) 94.9% shift 77 deg. S=3% (yellow-green) At this point, something I have been thinking about seems to become more obvious. This method is not measuring transmission, but rather the luminance of the swatch and would, therefore, be dependent on the aperture and transmission, maybe not an indication of true transmission. Henry, you seem to be controlling direction and intensity very well for an outside, illuminated flat sheet. How are you doing it??? This appears that it is going to be a valid test for comparisons done under the same conditions at the same time. It may even carry to independent status under more stringent conditions, but that may negate the simplicity sought. I have never done any formal testing of the Zeiss FL series, so I am not familiar with what bias I would perceive in the view. I, also, tried to stay within the confines of RGB, at least to the limit of my understanding of that system since I almost never use it. Ed will need to verify my RGB perceptions (I hope I did not mess them up to bad). BestRon</blockquote>

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