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Message:: [QUOTE="messydesk, post: 4642853, member: 1765"]OK, that didn't take too long.  Here's something that's close to axial lighting.  It's actually a really cheap ring light, made by cutting a hole in a piece of white paper and cramming it onto my lens as a reflector, pointing the lights up at the camera.  If you have a lens prone to flare, this won't work well. [ATTACH=full]1147278[/ATTACH] Here it is with the lights on.[ATTACH=full]1147279[/ATTACH] Here's what comes out of the camera.  Pretty useless picture, right?[ATTACH=full]1147280[/ATTACH] Here's its histogram. [ATTACH=full]1147281[/ATTACH]Note that less than 1/4 of the full dynamic range is used.  Therefore, with a camera that produces at least 11 bits per channel, I should be able to stretch this histogram out and still have a halfway decent 8-bit image.  Fortunately, mine has 14.  I'd like to say that simply adjusting the contrast for the entire image produced this, but doing that also revealed the unevenness of the lighting that was a result of having 2 bulbs and not more.  I had to make further local adjustments to get this: [ATTACH=full]1147283[/ATTACH] And its histogram: [ATTACH=full]1147285[/ATTACH]As mentioned in my previous post, this worked because the slab is free of blemishes.  A scratch, along with any shadow it cast on the coin would have been included in the detail that was brought out by enhancing the contrast, and you'd see them clear as day.[/QUOTE]