I recently heard about some macro shooters reversing a 50mm onto a 70-200 lens for super extreme macro. I wasn't sure if it would beat the combination of extension tubes, 100mm macro, and coupled 50mm, but 200mm is twice the focal length even though the lens won't focus as close as the macro. Anyways, I tried it out and it gives me almost the exact level of magnification with about an inch of working distance instead of roughly a centimeter. Relatively speaking, that's huge! That means that I can snake a flash in without crushing my subject. The downside is that the rig is essentially impossible to handhold. It's all set up on the tripod as a pseudo-microscope.
This is the underside of a purple DVD+R disc. The colors are just awesome...
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