Sony A58 Noise Reduction & Raw
Sony A58 High ISO Noise Reduction
The Sony A58 offers three High ISO Noise Reduction settings: "High, "Normal" and "Low". The camera's user manual doesn't say when High ISO NR kicks in, so we've included crops from the base ISO in the tables below.
See for yourself how the Sony A58's "High", "Normal" and "Low" High ISO NR settings compare to RAW without noise reduction under daylight-balanced lighting. (Note that these RAW images also have no sharpening applied, so they're a little softer than camera JPEGs at low ISOs.) Click on any of the crops below to see the corresponding full-sized image.
As you can see, some noise reduction is already applied at base ISO, as chroma noise is a little higher in the RAW crops, and even the Low setting reduced it. The difference between the three noise reduction settings is fairly subtle even at high ISOs, with just slightly higher noise levels as you reduce the setting, and NR remains quite strong even with the Low setting. We wish Sony would have offered a less heavy-handed setting, however we suspect the A58's target market won't mind that much.
It's quite evident that the Sony A58's image processor works hard to control noise at higher ISOs, as you can see fairly strong, coarse noise in the RAW crops. JPEGs are remarkably clean, though as you can see, fine and low-contrast detail suffers. Still, a pretty good performance for its class and price tag, as our print quality analysis attests to.