The A37's noise profile for JPEGs looks as you'd expect for a camera in this class: ISO 100 and 200 look good, you start to see artifacts at ISO 400, and the images are usable, depending upon content, up through ISO 3200.
Caption byLori Grunin
/ Photo by Matthew Fitzgerald/CNET
Not a stellar shot, but it accurately represents the general quality of the A37's low ISO sensitivity photos.
(1/100, f5.6, ISO 100, spot meter, AWB, 18-135mm lens at 18mm)
You can see the noise mottling in the sky and the detail degradation on the clock, but this would be quite usable scaled down a little. Also, a lot of shots of the clock face taken with other cameras/lenses display serious fringing on the high-contrast edges; here it's not a problem. I'm not sure if it's doing correction in-camera, though.
(1/80, f5, ISO 1600, spot meter, AWB, 18-135mm lens at 55mm)