Boy, what a response we got on this thread. Sorry to see so many people get up in arms. Anyway, I thought you might like to see the type images we're creating in my office and why we were debating lighting. We are not concerned with the amount of light - we assume a daylight setting. We are more interested in the 3D look than whether it is clinically correct. I just need to illustrate to students so that they can tell whether a part is a cylinder or a flat piece of metal. The image below is part of a larger piece that goes into flash and becomes animated.
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