In practice it is all too easy to underexpose so as not to blow highlights, which for most cameras results in quality losses that drop below an acceptable threshold for darker areas. So I see this comparison as highly relevant in choosing a camera system. That is why I have long favored the Nikon D810 with its ultra-clean ISO 64 over any Canon offering.
Two frames are shown here, both at f/8. One frame was shot two stops underexposed accidentally (1/1000). A moment later, the frame was shot again with two stops more exposure (1/250). I wondered how well the image quality would hope with the underexposed frame versus the optimal exposure frame, particularly given the shadow boost and push and fairly aggressive sharpening of Amount = 25.
Black and white conversions often place greater demands on pixel quality, since some color channels may be emphasized and those channels by themselves may be noisier and/or just become noisier by being, in effect, pushed considerably. For that reason black and white renditions are also shown in this example.
Presented in both color and black and white. Includes images up to full resolution, ACR processing settings and RawDigger histograms.
This image could not have been made with color reversal film; it would have consisted of a nearly black foreground in order to capture the sky without blowing out. Aggressive contrast control was used to brighten the foreground area, including a 2.5 stop push for the underexposed image.