The Canon EOS 5D Mark II is one of the most highly regarded DSLRs of all time, so the 22.3-million-pixel Mark III upgrade has a great deal to live up to. How will it fare?
The dynamic range of the EOS 5D Mark III is generally good, with the camera doing a fine job of making sure there is highlight detail. Of course, this sometimes leaves shadows slightly underexposed, although enough detail can be recovered without introducing noise, particularly at lower sensitivities.
Photographers who capture images as raw files have far more scope for recovering highlight and shadow detail in raw-conversion software. However, those shooting JPEG images may want to take advantage of the 5D Mark III’s highlight tone priority mode.
This seems to work by underexposing images to retain more highlight detail, and then boosting the shadows and midtones to compensate for the underexposure. I found that the reduction in exposure was usually as little as 0.3EV, which is enough to recover some finer highlight details while only requiring a slight boost to shadows.
This means that noise in these darker areas doesn’t become much more of an issue. Once again, though, to minimise the effect of noise, I would recommend using the highlight priority tone only on sensitivities below ISO 400.