Verdict
There is no doubt that the Sigma SD1’s unique Foveon X3 sensor means that the final images from this camera in a variety of settings stand out from the other two models – for good and bad reasons. The SD1’s resolution detail at lower sensitivities is truly staggering, although it is no match for the 40-million-pixel 645D.
There is a clear gap between each of the three cameras in this investigation. Unfortunately, there are more areas where the SD1’s sensor falls short. Dynamic range is rather limited for a camera at this price range, and its ability to control levels of noise satisfactorily at higher sensitivities does not stretch higher than ISO 800.
Let us not forget just how expensive the SD1 is. In proportion to its overall quality, one would hope to pay around a third of its asking price. This is not a satisfactory alternative to a medium-format camera. To date, however, when used at ISO 100 and 200, the resolution of the SD1 is unmatched by cameras using a regular 14MP sensor.
Sigma has built on its previous flagship model, but the Foveon sensor still shows signs of flaws in certain areas of image quality and, as such, the SD1 is likely to please only a limited crowd.
