We shoot a specially designed chart in carefully controlled conditions and the resulting images are analyzed 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 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 Panasonic ZS25's images produce a very similar signal to noise ratio to the Sony HX20V, Panasonic TZ25 and Canon PowerShot SX260 HS, though they are slightly weaker than the Samsung WB850, throughout the sensitivity range.
JPEG dynamic range
Results for dynamic range are a little more spread out than those for signal to noise ratio, with the Panasonic ZS25 coming in stronger than the Sony HX20V and Canon PowerShot SX260 HS at every ISO setting. The TZ35 shows a very similar dynamic range to the Panasonic TZ25 throughout the sensitivity range, while it's similar to the Samsung WB850 at lower ISOs, before the Samsung overtakes it at ISO 400 and 800. At ISO 1600 and above the ZS25 overtakes the Samsung and the TZ25.