Had a couple of real turkeys in my shots from yesterday. But because I shoot in RAW format, which retains all possible image information, and because I use good software, I can save shots that, in the past, would have been unequivocally unusable. For instance, the overexposed shot on below is the original, while the one below that is the "saved" version.
Those are YMCA team members, BTW.
A professional application's tools go a long way toward enabling this resurrection, especially using built-in macros like Lightroom's Auto-Tone preset. That won't do the job 100% (and can sometimes make the image worse), but will do a lot of the work here. Color temperature and fine adjustments to color curves are still needed. Often the software will boost the contrast too much and lose detail in the blacks and whites. This can be recovered, though usually at the expense of a slightly "greyer" look. In over- and under-exposure cases, though, some areas simply can't be recovered, as those pixels have been recorded at a full 16-bit black or white.
Here, the process is used to bring up a hopelessly underexposed image to something of at least documentation value:
Had it not been for the ability to extract fine gradations of "black" from the RAW file, this photo would have been dead and buried. The only reason I didn't automatically delete it was because I could see just enough that I knew I liked the composition. Not all pictures can be resuscitated this well. And were I shooting in JPEG format - where the camera is set to save only high-res JPEG copies rather than the RAW file - I wouldn't be able to do this at all.