Sony Cyber-shot RX100 IV review

We've put the Sony RX100 IV through our full set of lab tests to check its resolution, dynamic range and signal to noise ratio (noise). We've also picked out three of its key rivals, so that you can compare them for performance directly. The Panasonic LX100 has a larger Micro Four Thirds sensor, and is probably the top high-end compact camera with a zoom; the Canon G7 X, like the Sony RX100 IV, uses a 1-inch sensor; and the Fuji X30 is more of an old-school high-end compact with a smaller sensor than the rest, but a good lens and a good set of features for the money.

We've carried out lab tests on the Sony RX100 IV across its full ISO range for resolution, noise (including signal to noise ratio) and dynamic range. We test the JPEGs shot by the camera, but we also check the performance with raw files. Most enthusiasts and pros prefer to shoot raw, and the results can often be quite different.

Sony RX100 IV resolution charts

We test camera resolution using an industry-standard ISO test chart that allows precise visual comparisons. This gives us numerical values for resolution in line widths/picture height, and you can see how the Sony RX100 IV compares with its rivals in the charts below.

JPEG resolution analysis: The RX100 IV is just about the best in this group for resolution when you're shooting JPEG images, although the Canon G7 X runs it a close second. Surprisingly, perhaps, the Panasonic LX100 is in third place – but then although its sensor is larger, its multi-aspect ratio sensor means it's limited to a little over 12 megapixels. Less surprisingly, the X30 brings up the rear – it also has a 12-megapixel sensor, and a relatively small one at that.

Raw (converted to TIFF) resolution analysis: The pattern is repeated for raw files, with the Sony RX100 IV narrowly beating the Canon G7 X, and the Panasonic and Fuji in third and fourth places respectively.

Sample resolution charts

This is the chart we use for testing camera resolution. The key area is just to the right of centre, where a series of converging lines indicates the point at which the camera can no longer resolve them individually. We shoot this chart at all of the camera's ISO settings, and here are two samples at ISO 200 and ISO 6400.

ISO 200: Click here for a full-size version.

ISO 6400: Click here for a full-size version.