Up first I take a look at straight up performance. Click on each image to bring up the full size comparison. Each image features three 100% pixel crops at one ISO. One of the focus point (the fruit cookie in the center), one of the gray patches on the color chart (to evaluate mid-tone noise) and one area of the bottle of cranberry juice, to show how the cameras deal with high saturation color in the reds (which is often a problem for digital cameras) as well as deep shadow and deep single color shadow noise performance. This third crop is kind of a torture test for digital. Again, these crops are with identical RAW processing for all images:
Looking at the above crops, let’s start with base ISO (ISO 160 on the GH2 and GX1, ISO 100 on the 1Ds II). The Canon appears to have slightly better dynamic range in this shot, as evidenced by the increased shadow detail on the raisin in the cookie. Highlight detail appears to be quite similar. All three cameras hit saturation limits on the highlight of the red bottle, but all three also rolled off into this highlight area gracefully. The 1Ds II provides a slightly cleaner file at base ISO, with the gray squares showing no visible noise, while the GH2 and GHx1 have very slight fine-grained noise in these areas (not that you’d see it on a print). However, one interesting thing is that the Micro 4/3 cameras in this test resolve more detail. The cookie crop shows more fine detail on both the GH2 and Gx1 shots, while there is finer definition on the color checker chart lines as well. The Leica 25mm also appears to render a little more contrast in the image, but that is likely due to lens design more than the camera. Both lenses should be extremely sharp in this range, so it is likely that the higher visible resolution in this test is a result of a lighter anti-aliasing filter on the Panasonic bodies.
At higher ISO, the GH2 and GX1 maintain their detail lead, and the 1Ds II retains it’s noise control advantage. Note that at ISO 1600 and ISo 3200, the GH2 starts to exhibit a color shift towards green. This was one of the weaknesses of the GH2 at high ISO, and it is nice to see that the GX1 not only controls noise ever so slightly better, but color remains essentially perfect even at high ISO. The 1Ds II’s noise profile is finer grained than either of the two Panasonic bodies. With similar developing, it appears to my eye that the 1Ds II has about about a one stop advantage at ISO 1600 to ISO 3200.