There has been some discussion about noise level of underexposed shadows from Canon EOS 5D MkII at ISO 100 compared to other FF cameras. I usually don’t have to push the exposure and find the problem theoretical, but I found the issue intriguing and did some tests.
- I do not think it is a good idea to underexpose like that, I am merely looking at the behavior of the camera or the raw converter
- The noisy samples are 100% crops from 21MP sensor and I the impact on actual prints will be minimal
- It is possible that Canon or Adobe will be able to mitigate the problem in next update of Canon firmware or ACR update
Image straight out of the camera with default ACR settings, no corrections applied.
Here is the actual ACR settings from the Basic tab. In addition to that, I tweaked the Luminosity and Color Noise sliders so that the noise is minimized, but not so much as to introduce the compact camera look. I use custom camera profile based on the GMB checker. I also tried the canned Adobe profiles as well, they produce different levels of noise, some are higher than the examples here and some are lower.
100% crop from the above image. The image has been pushed by 1.5 EV. Given the heavy exposure correction, it looks decent to me.
Another 100% crop from the above image. The image has been pushed by 1.5EV. It is possible to tweak the curves and noise slider so that there is no noise on the roof or in the sky, but other areas of the image then start looking like a compact camera picture with removed noise.
Another 100% crop from the above image. Again, pushed by 1.5EV. If more noise removal is performed, the rendering of the branches and edges looks like a compact camera shot.