Panasonic DMC-GF1 High ISO RAW
Panasonic GF1 High ISO RAW Image Quality
We've recently started looking at RAW files converted with dcraw, an excellent freeware raw converter. dcraw usually offers timely support for the latest cameras, but more importantly, it does not apply any noise-reduction, sharpening or other corrections such as geometric distortion correction to the output files. (We found that Adobe Camera Raw still applies some limited noise-reduction when its NR settings are set to zero, and it also applies other corrections depending on the make and model of the camera). There will always be differences between RAW converters, in terms of the sort of demosaicing algorithms they use (the processes by which they convert the separate Red, Green, and Blue data sets to an array of full-color RGB pixels), but dcraw seems to use a fairly generic algorithm that delivers good sharpness with relatively few artifacts, and can be counted on to not apply any noise reduction if you don't want it to.
Below are crops from Panasonic GF1 high ISO RAW files compared to RAW files from other Micro Four Thirds models: the Panasonic G1, GH1 and Olympus E-P1. All were converted with dcraw with no noise reduction or sharpening.
As you can, the Panasonic GF1 is very similar to the GH1 in terms of raw sensor noise. Color response is a bit different though. You can also see a hint of banding in the GH1's output that isn't there for the GF1 or G1. Both the GF1 and GH1 are slightly cleaner than the G1. The Olympus E-P1 appears to have a slight edge over the Panasonics in terms of high ISO noise.
Let's see how the Panasonic GF1 compares to some similarly priced DSLRs:
As you can see from the above crops, the Canon T1i and Nikon D5000 SLRs with their larger, APS-C sized sensors have a considerable advantage when it comes to noise. The Olympus E-620 has a Four Thirds sensor which is the same size as Panasonic GF1's sensor, so there's not much difference there.