As we also pointed out in our test report, several other factors contribute or detract from the DP1's image quality, including the accuracy (and speed) of the focusing system, the metering system, and the quality of the lens. However, Sigma makes another claim for the DP1 that impacts image quality indirectly, and there wasn't room in the report to delve deeper into this claim. According to Sigma: "The DP1 uses a wide-angle lens with a focal depth equivalent to 28mm on a 35mm film camera. But because of its large image sensor, the depth of field is shallow. So, shooting at close range or with a wide-open aperture, you can use the kind of natural out-of-focus effects you'd expect of an SLR."