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Message: <blockquote data-quote="elkcub" data-source="post: 1390738" data-attributes="member: 14473">With reference to Post #21, as Ron mentioned the various areas are not quite uniform.  The following RGB readings, therefore, are estimates of an average value. Four section panel:Background  227, 228, 232  (blue bias)Upper Left  216, 216, 216  — 8x42 Ultravid  Lower Left 215, 215, 215 — 8.5x42 ELUpper Right 218, 220, 217 — 7x42 Zeiss (slight green)Lower Right 215, 212, 207  — 8x42 LX-L (slight red-green)The two section Zeiss FL panel:Background  227, 228, 232 (same blue bias)Upper  218, 220, 217  green bias, (2% greater transmission?) — 7x42 FLLower  213, 215, 212  green bias  — 8x32 FLComments about color tint are based on the RGB weights, but also correspond to my subjective impressions of the various swatches in the panels.The way I tend to think of this is that the background models daylight, perhaps as seen by the eye, and the various swatches tell us how this is modified by the instrument.  This is the work of the optical transfer function for each instrument.  So, for example, the Ultravid and EL filter out some blue to produce an equally weighted RGB, whereas the FLs, and LXL change the bias from blue to green or red, respectively.  With the appropriate rotation matrix, these values could be represented in HSV format that Ron prefers, but the information content remains the same.  Ed</blockquote>