Allium, photo by Harold Davis. View this image larger.

This is a close-up of a red onion cut against the grain. I photographed the onion on a black background using a single spotlight bounced off the ceiling.

Here’s the exposure data: Nikon D300, 200mm macro, 36mm extension tube, three exposures (20 seconds, 30 seconds, and 60 seconds), each exposure at f/25 and ISO 100, tripod mounted.