ISO Sensitivity / Noise levels (contd.)

Noise reduction settings

The G1 has five levels of noise reduction from -2 to +2. The graph below shows the effect of the various settings from ISO 800 upwards. As you can see the difference, even between the extreme settings, is fairly small, particularly at ISO 800.

Indicated ISO sensitivity is on the vertical axis of this graph, standard deviation of luminosity on the horizontal axis (note that the standard deviation scale here has been extended compared to the graphs on the previous page).

Noise reduction crop comparisons (ISO 800 - 3200)

The sample crops confirm what we can see in the graph above. The difference between settings is visible but not as significant as you'd expect. If you want to preserve detail we'd suggest staying away from the +2 setting.

ISO 800
NR -2

ISO 800
NR Standard		 ISO 800
NR +2
ISO 1600
NR -2 		ISO 1600
NR Standard		 ISO 1600
NR +2
ISO 3200
NR -2 		ISO 3200
NR Standard		 ISO 3200
NR +2

RAW noise

Finally let's take a look a the G1's raw output next to two APS-C sensor DSLRs. Removing any in-camera noise reduction and processing the images using Adobe Camera Raw (V5.2 in this case, all NR set to 0) gives us the nearest thing to a 'level playing field' for assessing the relative noise levels of the three cameras' sensors.

Despite the G1's sensor being more tightly packed than the Sony's the two cameras show comparable levels of both luminance and chroma noise at higher ISO. Considering this, it's very interesting to see how much difference there is between the high ISO JPEG of the two cameras (see previous) page. Panasonic and Sony are clearly taking very different approaches to in-camera noise reduction. The Canon EOS 450D delivers the visibly cleanest high ISO RAW images in this comparison.

Panasonic G1
ISO 800 RAW

 Sony A350
ISO 800 RAW		 Canon EOS 450D
ISO 800 RAW

Panasonic G1
ISO 1600 RAW

 Sony A350
ISO 1600 RAW		 Canon EOS 450D
ISO 1600 RAW
Panasonic G1
ISO 3200 RAW		 Sony A350
ISO 3200 RAW		 n/a