Amazing Lightning Photography

This is an amazing lightning photo I saw recently and I have been trying to figure out how they did it. I love the colors and the light effects with the clouds. Any ideas what kind of equipment he might have been using?

Here is a link to the full size lightning photo.

He said some photoshop work was involved -- mostly using the healing brush to tone down or eliminate lights from the town of west richland on the hillsides. Color balance also tweaked for aesthetic effect.