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
These results show that JPEG images from the Nikon D7100 show among some of the weakest signal to noise ratios of the cameras here, falling behind the Nikon D5200, Nikon D7000 and Nikon D600 throughout the sensitivity range. The D7100's JPEGs show a greater SNR than those from the Canon EOS 7D and Pentax K-5 II at ISO 100-800, but fall behind the Canon at higher ISOs, and alternate with the Pentax for last place from ISO 1600 to the top of the sensitivity range.
Raw signal to noise ratio
The signal to noise ratios of the TIFF images (after conversion from raw) from the Nikon D7100 are weaker than those in its JPEG images, with weaker ratios than all the cameras at ISO 100-800. The D7100's TIFF images always show less signal to noise ratio than those from the Nikon D5200, Nikon D7000 and Nikon D600, but they beat those from the Canon EOS 7D at ISO 1600, before falling behind again for the rest of the range. At the top of the range, the D7100 has a greater SNR than the Pentax K-5 II.
JPEG dynamic range
The Nikon D7100's JPEG results for dynamic range are more impressive than those for signal to noise ratio, at least at lower sensitivities, with the camera producing the greatest range at ISO 100 and remaining in the top three performers up to ISO 400, alongside the Nikon D5200 and Nikon D600. At ISO 800 it falls behind older brother the Nikon D7000, before steadily falling to produce a weaker range than the Pentax K-5 II at ISO 3200 and 6400, and a slightly weaker performance than the Canon EOS 7D at ISO 12800.
Raw dynamic range
This chart indicates that TIFF images (after conversion from raw) from the Nikon D7100 aren't as strong at lower sensitivities as its JPEG images, coming in third strongest at ISO 100 and 200, again behind the Nikon D5200 and Nikon D600. In the mid range the D7100's TIFF performance drops below the Nikon D7000 and Pentax K-5 II, the latter of which is much stronger in this test. At ISO 1600 and above the D7100 overtakes the D7000, at ISO 3200-6400 it also overtakes the D5200, then at ISO12800 and above it beats the Pentax. The D7100's TIFF images beat the Canon EOS 7D's for dynamic range at every sensitivity setting.