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Message: <blockquote data-quote="Surveyor" data-source="post: 1392952" data-attributes="member: 50720">Ed, Sorry to be so long getting back to you but I am having computer problems at work and have to deal with the stuff that pays the bills first. Concerning post #31, I am glad I did not stray too badly. About the difference in the HSV, I think this probably concerns settings of the converters. I have attached a jpg of the calculator I use and for HSV I use the format 0-360 degree for H and 0-100% for S and V. The converter I use will allow me to select from 6 formats for HSV. From the results you show, I think your calculator may default to 0-255 counts for all three values (21/255=30/360, 4/255=2% and 241/255=95%). The difference we have in T% or luminance is that you are using the straight RGB values and I used the CIE luminance value, or L in the Lab definition. The numbers will track in the relative sense, but does point out the need for a good protocol definition. Henry, ED; Like Henry, I am surprised by the high values for the assumed T%. At this point, I am thinking what we are seeing is an average of three lens systems, the bino, the camera and the CCD photosites. We are probably also getting an electronic gain figure from the camera program that charges the CCD for a given exposure setting. If this is indeed the case, I think the T% values are more along the lines of a random distribution and are going to be undependable for the use intended, but this is strictly conjecture at this point. Based on the procedures I have to go through when doing transmission measurements, I am going to assume that a simple transmission estimate is fairly unlikely. Controlling directionality and intensity setup take far longer than actually doing the measurements. For instance, a tightly collimated beam with a maximum dimension of ½ the aperture and preferably less controls directionality. Anyone who has tried to collimate a visible light beam down to close to laser dimensions will understand the problems. Controlling the intensity is a set of problems all their own. I have attached a jpg of three of the binos referenced (although 20mm versions) that show the levels we should be getting close to but I have never had the chance to test any of the FL range. The values Henry referred to would be typical peak values. The average values for the range of 380-780 nm would be: Ultravid=76.05%Swaro=69.77%LXL=79.78% For the photopic range of 500-600 nm (I assume camera sensitivities peak in this range, but do not know that for fact): Ultravid=88.7%Swaro=87.8%LXL=85.6% The color difference is another story. These appear to be tracking very well to me. As Henry noted the difference between the Swaro and Ultravid is very close to the same. Look at the transmission curves and this is confirmed, the shapes are remarkably similar. The colors from the color test were very close also, the color temperature only differed by 11K. You can see the red bias in the LXL plot, very consistent with Henry’s photos. Still, a method that deserves more study and experimentation. Best to all.Ron</blockquote>

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