Just received my Canon L 50-300mm f/4.5 zoom and stepped outside my apartment to test it out on the moon. Here's the best shot. It is cropped from the original. Shot it at f/5.6 on the GH2 at the full 300mm zoom, the crop on the GH2 gave me a little extra zoom to an effective FOV of 600mm I believe. 

Minor editing in photoshop, just some leveling to bring out some details in the bright side which were nearly washed out.

More tests to come!

Took my Panasonic GH2 out with my Canon FD 35mm (concave) f/2.0 lens for some fun at the Minnehaha Bluegrass Festival in Minneapolis, MN. Here are a few shots from around the festival.

Most of the images shot at f/2.8, 160 ISO, and then proper exposure achieved with SS (generally ranging from 1/160th to 1/500th). The lens is nice although it is a strange length on the MFT sensor. Chromatic aberrations are visible in high contrast shots. (No filters were used)