For freedom to configure light sensitivity in response to shooting conditions, professionals will surely appreciate the wider-ranging standard ISO speeds of the EOS-1D Mark III, from 100–3200. ISO sensitivity is displayed in the viewfinder as well as top LCD for user-friendly adjustment and fewer missed opportunities.

Settings are selectable in 1/3- or whole-stop increments and may be set as low as 50 or as high as 6400 through the ISO expansion menu. Combining high ISO speed with a high shutter speed, the EOS-1D Mark III produces blur-free photos even when assignments or shoots involve dark settings. Note: All references to ISO sensitivity are based on Recommended Exposure Index.