Compare and contrast RAW file quality delivered by cameras tested by DxO

If you are fascinated by digital camera sensor technology and RAW file image quality, you will love DxOMark, a new website from DxO Labs.

I have a great deal of time for DxO. The company, based in Paris, France, has some very clever people at its heart and they are the digital imaging experts behind a surprisingly wide array of optics-related solutions, from DxO Optics pro, the remarkably effective profile-based image-fixing and enhancement software package, through to the development and licensing of designs for digital camera optics in both cameras and camera phones. Here at DPNow we use DxO Analyzer, a professional suite of tools for assessing digital image quality.

So today's announcement of the launch of a new DxO website resource for anyone interested in the quality of digital camera sensors and the RAW image files these cameras produce is very interesting. The site is called DxOMark, which is also the name for the overall rating that DxO has developed to assess the quality of the RAW file output of cameras it has tested. There is a break down of test result data including Low light ISO performance, Dynamic Range, Tonal Range, and Colour Sensitivity. An aggregation of the results forms the DxOMark rating. Both compact digital camera models (which can save RAW files) and DSLRs are tested.

51 cameras have been tested, to date. The tests evaluate the RAW image data that the camera generates. DxO use their own software tools to decode and analyse the RAW file data. In a way, the DxOMark is not just a rating of RAW file quality, but of the performance of the camera's sensor and its implementation in the camera. RAW data quality is important, because the same data serves as the basis for JPEG files generated by the camera as well. Even if you don't use RAW files yourself, the DxOMark will have some bearing on the camera's potential for producing good quality JPEG files.

Camera models tracked over time

The DxoMark database tracks the quality of RAW file output from numerous cameras over time and it's very interesting to compare results from cameras of different resolutions, pixel densities, sizes, etc. Currently, DxO rates the output from the Nikon D3 as top of the pile, with a DxOMark of 80.6, closely followed by the Nikon D700 on 80.5, and the Canon EOS-1Ds Mark III (80.3). Fourth is the Sony Alpha A900 (78.9). What's probably more useful is to look at the break down of the test results.

The lowest ratings are almost all compact cameras, though the Nikon D2H, a four megapixel high speed DSLR camera developed for press photographers, is third from bottom out of 51 cameras tested.

Quality versus pixel pitch

DxO's results do intrigue me because there is a wide variation in performance from different cameras that use very similar specification sensors. And you can't rely on the density of pixels on a sensor as a sure-fire indication of quality. Normally, a more densely packed sensor, with a smaller pixel pitch, should - in theory - result in a lower dynamic range and more noise. But witness the 6MP Nikon D40, compared to the 10MP Nikon D40x. Statistically, there is hardly any difference in the dynamic range and high ISO performance of the two cameras. Meanwhile, the 12MP Nikon D300 is better than either.

In general, DxO's data does point to a steady improvement in the performance of cameras over time, which is good news for photographers. So if you are at all interested in camera performance, you should bookmark DxOMark, and here at DPNow we will be referring to and quoting data from DxOMark.

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DxO launches DxOMark online camera sensor performance technical analysis resource

DPNow DxO launches DxOMark online camera sensor performance technical analysis resource
Here is a summary or excerpt from an article that has just been published on DPNow: DxO Labs, the P... (more)

Ian Re: DxO launches DxOMark online camera sensor performance technical analysis resource
I think this is really intersting - you can compare the sensor performance of your camera to aroun... (more)

Stephen Re: DxO launches DxOMark online camera sensor performance technical analysis resource
Indeed there are, they have certainly surprised me when comparing some cameras. The widely held be... (more)

Ian Re: DxO launches DxOMark online camera sensor performance technical analysis resource
Low light high ISO noise and dynamic range are not exactly related. Dynamic range is a quality of ... (more)