If you like that distinctive, three-dimensional shadow wrap in your portraits generated by a ring flash but don't necessarily want to carry around a cumbersome and expensive ring flash all the time, maybe it's time to switch to Ray Flash.

Never heard of Ray Flash? Until recently we hadn't either but are impressed with the ingenuity of this strobe modifier distributed by ExpoImaging. (Maybe it's because of the popularity of Web sites such as Strobist.com and others, but all the best inventions in photo gear these days seem to be centered around portable flashes.)

Ray Flash is an adapter that fits right over the head of your hot shoe flash and is designed to mimic the lighting effect from a traditional ring flash. From a distance, Ray Flash actually looks quite a bit like a ring flash as well.

The difference is that since Ray Flash uses your on-camera strobe to generate light, there are no electronics or flash tubes inside so it's lightweight and doesn't require any additional cables.

Light shapers inside the circular Ray Flash distribute the light so it projects evenly around the lens, creating that eye-catching shadow around your subject while keeping the person or object you're photographing virtually shadowless.

When using Ray Flash, the TTL functions of your on-camera strobe function normally, while manual exposure control requires a light meter. The 16-ounce Ray Flash is designed to fit the Canon 580EX (I & II), Nikon SB800 and Nikon SB900.

ExpoImaging says no plans are in the works to have it fitted for other brands or models, but some users have reported that Ray Flash does work with other flash units. The Ray Flash's 4 1/8-inch internal diameter allows it to work with most professional lenses from both Canon and Nikon.

Cost: $199 Further information: www.expoimaging.net