5D classic vs 1D Mk III at ISO 3200, f/8. 5D at 1/10 second, 1D3 at 1/8 second (the 5D and earlier Canons were about 1/3 stop more sensitive than thier ISO setting indicated so this compensation equalizes the exposure).

Picture style was neutral with sharpening set at "3", noise reduction of "0". Downrezzed the 5D's image to match the pixel dimensions of the 1D3. These are 100% crops.