DxOMark recently published data about the Sony RX100 and Olympus E-M5 sensors, prompting some to recognize that the RX100 actually has a tiny bit more measured dynamic range (DR) than the E-M5 while both have a fair bit more DR than the Panasonic GX1: Since I have all three of these cameras on hand, I thought this would be a good time to show what I consider to be the value as well as the limitations of these test scores. Are these DR differences observable in practice, and are these numbers really representative? In order to carry out this test, I chose a scene in my home with consistent lighting and a range of very bright to very dark, shooting each camera at base ISO with a matched angle of view and matched DOF throughout a variety of exposures until I obtained one RAW file from each camera with a similar degree of recoverable highlight detail. Here was the test scene as seen by the GX1 (left) and RX100 (right): In the following 100% crop comparisons, the RX100 is at a slight disadvantage because I have not matched the output size and the RX100 has a higher megapixel count, but I think it will be clear that the small difference in megapixels has little influence on some fairly obvious differences. Here are the highlight regions from the files at 100%, "pulled" to reveal that recoverable highlight details are fairly well matched: When you look at the pushed shadow regions from the same files, it's obvious that the RX100 can capture details across a wider swath of contrasting shadows and highlights: Based on the "eye test", the measured DxOmark DR result of 10.6 (GX1) and 12.4 (RX100) stops seems believable. Now let's look at the E-M5 (left) compared with the RX100 (right). First the highlights showing that the files were selected to roughly match in terms of recoverable highlight detail: Next the "pushed" shadows: In this case, the practical results don't seem to bear out the measured results of 12.3 (E-M5) vs 12.4 (RX100) stops. DxOmark has the following to say about their DR measurements as pertains to landscape photography (source): In summary, DxOmark results are useful but limited. I'm hoping to see one of the big review sites adopt DxOmark's rigorous testing methods and use them to produce test results which can be evaluated with the "eye test".