Ouch alert! Sigma SD1 high-ISO test-samples (compare to Nikon D7000)
Rock and roll ain't noise pollution said the noise-peeping team of AC/DC Productions, but the Sigma SD1 might be! Focus Numerique has published their standard ISO-range samples (computer translated) taken with the Sigma SD1, which you can also compare with other cameras in their system. Below the SD1 samples you can see the equivalent samples from the Nikon D7000 with the "magic sensor". Both sensors are APS-C and about the same size. The RAW files from each camera are available at the aforelinked page, look at the links right below each block of ISO-range pictures.
On the plus side, FN notes that you can get different results using RAW developed with the Sigma software vs the in-camera JPEG engine. Now if this was a $1X00 DSLR one could argue this camera is a reasonable trade-off for studio and ISO 100/200 shooters. But this being a $6000+ DSLR performing like this, well, ouch! Some could argue that high-ISO SD1 shots are more expensive than Monet before they even make it to print ;-)