Panasonic GH1 High ISO NR
Panasonic GH1 Noise Reduction
The Panasonic GH1 offers 5 levels of noise-reduction settings also allow you quite a bit of flexibility in choosing how you want to make the trade-off between subject detail and noise levels. The GH1 applies NR to its JPEGs at all ISOs, so we've included crops at all ISOs. The combination of shooting with NR turned down to the lowest setting (-2) and using a good noise-filtering program after the fact can produce very clean images with lots of fine detail in them. RAW images with no NR or sharpening are also shown for comparison.
See for yourself how the noise reduction works under daylight-balanced lighting. Click on any of the crops below to see the corresponding full-sized image.
The above crops show the effects of four (-2, 0 and +2) of the Panasonic GH1's five levels of noise reduction available, under the studio HMI lighting we use to simulate daylight. A RAWimage with no NR applied is also included for comparison. To our eyes, the default (0) level of noise reduction strikes a good balance between noise and subtle subject detail, although the red fabric swatch presents a real challenge, as it does for virtually all cameras we test. Cranking the noise reduction setting up to +2 produces very smooth-looking images, while still maintaining good detail in areas of high local contrast (as seen in the circular scale), but a lot of detail is lost in areas of subtle contrast (the red fabric swatch is a particularly challenging subject, and the detail loss there is worse than you'd find in most real-world examples). At the other end of the scale, the -2 noise reduction setting leaves a lot of noise in the image, but also leaves the subject detail largely undisturbed: Use this setting if you have good third-party noise reduction software; with appropriate processing, the result could be quite good. You should be able to do even better working from the RAWfiles.
But how does the Panasonic GH1 compare to the G1? See the following table which compares the default setting as well as RAW between the two siblings.
To our eyes, the GH1 has a slight noise advantage over the G1, and it's not just improved noise reduction. Even the RAW files are a touch cleaner. Unfortunately, the Panasonic GH1 seems to suffer from moderate banding at ISO 800 and up, more so than the G1.