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<p>[QUOTE=&quot;rmpsrpms, post: 2613484, member: 31773&quot;]The issue is that the camera&#039;s interpretation of -0.7EV is based on its internal metering. Do you have a live histogram available? That&#039;s usually the best way to eliminate hotspots, especially for copper coins. Most cameras meter luminance, so they will allow an individual color channel to blow out as long as the luminance is OK. For copper, this means the R channel is very easy to blow out, and is one of the reasons copper is harder to image than silver. If you use the histogram in RGB mode (not luminance) you can adjust the exposure until the R channel is just below saturation. If you don&#039;t have a histogram to manually meter with, you will need to ensure the camera is metering on the highlights. And if that can&#039;t be done, then all you can do is take the shot, view the histogram (or mouse over the highlights and view the RGB values) in an image processor, re-adjust the exposure, take the shot, and repeat until you are no longer over-exposing the image.</p><p><br /></p><p><br /></p><p><br /></p><p>Really excellent question. My reference is ODFL (Overhead Diffuse Fluorescent</p><p>Lighting). This is the color I would see when buying or selling the coin at a coin show. I find that diffused Jansjo LEDs, shot from a high angle, with WB properly set, very closely approximate these conditions.</p><p><br /></p><p>edited to add: another valid reference would be incandescent flex lamp. Some dealers use these at their tables. Turns out the Jansjo LEDs do a decent (though not perfect) job of matching to incandescents.</p><p><br /></p><p>another edit: here is your last image showing the blown out red highlights. As you can see, a significant amount of the image is over-exposed in the R channel, with a few pixels showing G blowouts as well. This means that all areas shown are not color-correct. Because they are blown out in R, this makes those areas appear less red than they should be.</p><p><br /></p><p><img src="http://i943.photobucket.com/albums/ad273/rparkhurst/01c%201931-S%20full%2003_A.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" />[/QUOTE]</p><p><br /></p>

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