This is a pretty good example of why it is better to underexpose than overexpose if you are in tricky lighting conditions. Sunday evening I was doing some sunset shoot tests and on my way back to my car saw this beautiful even light on the path I was walking on and a beautiful sunset. I literally had my Canon 5Dii (not Canon 5Diii) in one hand so I flipped it over to RAW and took 2-3 images as I walked. The first couple had the sky over exposed, so I closed my aperture down until I stopped getting all white in the sky (which is non-recoverable).
1/80, f5.6 ISO 400 – This is the before shot…And this is after I opened it in PS RAW and played with it a little. I will be the first to tell you, there are some real problems with the foreground, in that “fill light” essentially is acting as a very high ISO signal boost, including a lot of extra noise. The good news is though, at least there is information in those dark shadows, which make the image somewhat recoverable.
Take home lesson is this, if you are shooting an image with a wide range of dynamic light (bright sky with dark shadows) you are going to be better off underexposing the shadows to save the highlights, than you would be to blow out the highlights to evenly expose the sky.