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RAW noise

Finally let's take a look a the raw output of the EOS50D next to the ten megapixel 40D. Removing any in-camera noise reduction and processing the images using Adobe Camera Raw (without NR) gives us the nearest thing to a 'level playing field' for assessing the relative noise levels of the two cameras' sensors. Despite the fact that the 50D is the newer camera it shows visibly more chroma and luminance noise than the 40D. Considering the 50D's much more tightly packed sensor (4.5 MP/cm² vs 3.1 MP/cm² on the 40D) this comes hardly as a surprise. It would have been unreasonable to expect Canon's engineers to overcome the laws of physics.