We shoot a specially designed chart in carefully controlled conditions and the resulting images are analysed using DXO Analyzer software to generate the data to produce the graphs below.
A high signal to noise ratio (SNR) indicates a cleaner and better quality image.
For more more details on how to interpret our test data, check out our full explanation of our noise and dynamic range tests.
JPEG Signal to Noise Ratio
JPEG images from the Canon 5D EOS Mk III show a slight improvement in signal to noise ratio over the Canon EOS 5D Mk II at all but the lowest sensitivities. From around ISO 200 and above it also beats the Nikon D800 and Nikon D700.
Raw signal to noise ratio
TIFF images (after conversion from raw) have a consistently good signal to noise ratio across the sensitivity range comparing closely to the Canon EOS 1Ds Mk III and just having the edge over the Nikon D800. It also shows a slight improvement at all sensitivities over the Canon EOS 5D Mk II.
JPEG dynamic range
This chart shows that the Canon EOS 5D Mk III's JPEG dynamic range is very respectable, beating both the Nikon D700 and the Canon EOS 5D II, but it can't beat the Nikon D800's JPEGs until around ISO 3200.
Raw dynamic range
TIFF files (after conversion from raw) have a high dynamic range with results comparing closely to the Nikon D4 and D800. Compared with the Canon EOS 5D Mk II, there is a marked improvement showing over 2EV greater range at the lower end of the sensitivity scale.