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 the Canon PowerShot A4000 IS's JPEG files have a slightly lower signal to noise ratio than those from the Olympus SH-21, Panasonic Lumix FS35 and Canon IXUS 230 HS, although at the top end of the sensitivity range they all produce a very similar result. The Canon A4000 is most similar here to the other Canon.
JPEG dynamic range
Results for dynamic range are much more spread out for these cameras, with the Canon PowerShot A4000 IS's JPEG images starting out better than all the other cameras' at lower-to-mid ISOs, before falling to finish just above the Olympus SH-21 and Panasonic Lumix FS35 and a fair bit below the Canon IXUS 230 HS at the top sensitivities.