I have been playing around with my cameras and lights a lot lately. This morning I spent a while going through the 5D Mk2 user's manual. Jeez, there is a lot of stuff in there. One thing that I found was Peripheral Illumination Correction which can be applied for certain lenses. The 24-105 is included but the 100-400 is not, which is a shame. Well almost. As you guys probably know vignetting can easily be removed with Lightroom or Photoshop. So I thought that was going to be an important discovery, but it wasn't. I wanted to take some test shots outside just for the hell of it. We had a rain last night, so there were some nice raindrops to photograph.