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Message: <blockquote data-quote="henry link" data-source="post: 1390581" data-attributes="member: 6806">Ron,Thanks for all your work, again. The first thing I notice is that the background color and FL crop from the two slides don't generate exactly the same RGB numbers. I don't understand that since they are the very same images transferred from iPhoto to PowerPoint, though I may have resized and reshaped them slightly differently once they were transferred. Should we just expect some small differences in each transfer or should I avoid any resizing or shaping? As far as controlling intensity, I had to resort to very small crops (about 1" square) inside a 4" square I had penciled onto the background paper. I found I could see small differences in intensity within a crop by transferring a duplicate of it to PowerPoint, then juxtaposing the original and duplicate with different rotations and overlaps. I moved and adjusted the crops until I finally found a crop of pretty even intensity. Then I tried to match that with the same area on the background. Quite a pain in the rear.Today I tried something different, which is illustrated in the slide below. I used the controls in iPhoto to brighten the four "alpha" binocular samples so that they all  approximately match the background brightness which leaves only the pure color bias visible, like the smile of the Cheshire Cat. The iPhoto control of "exposure" assigns numbers to the increases. I don't know what the numbers actually mean, but this is what was required to bring  each binocular up to approximately the brightness of the background: Zeiss FL-.09, Leica Ultravid-.13, Swarovki EL-.15, Nikon LX-L-.17.Also, thanks Ron and Steve for the visual impressions. I think the Zeiss, Nikon difference is a pretty good test for red/green color blindness. And thanks, Ron #2, for the compliment only a true optogeek could appreciate. Henry</blockquote>

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