A friend of mine shot some quick raw files to compare the 5D2 and 7D in the case where the 5D2 is cropped to the same angle of view as the 7D (such as in a lot of wildlife photography). Here is the analysis of the test (with raw files):
7D compared with cropped 5D2
Some notes about the comparison:
- The JPEG compression is very light, but if you prefer completely uncompressed PNG files, just remove "-jpg" from the URL.
- The 100-400 and 100mm macro lenses were used, but I only ended up analyzing the macro shots in the above URL.
- The color temperature was very low, 2800K, and white balanced back to neutral, so the blue channel has quite a bit of noise even at ISO 100.
- Same 100mm f/6.3 settings on both.
- There was a bit of a brightness difference that required equalization in the raw converter. I didn't bother to preserve highlights while brightening with nonlinear EC or highlight compressing curve.
- dcraw was used to demosaic the files to ensure both were given exactly equal conversions.
- In the first two sets of comparisons, I upsampled both cameras to 36 MP so that the effect of the upsampling wouldn't unfairly penalize the 5D2. In the third set, both are downsampled to 8 MP
- ImageMagick was used for resizing and sharpening (same parameters for both).
Based on the comparison, I think I prefer the 7D for this type of circumstance. I hope you find it informative.