Noise and Noise Reduction (JPEG)

This is our standard studio scene comparison shot taken from exactly the same tripod position. Lighting: daylight simulation, >98% CRI. Crops are 100%. Ambient temperature was approximately 22°C (~72°F).

Note: this page features our new interactive noise comparison widget. By default, we show you the default noise reduction settings of the camera tested, and three other models of the same class. You can select from all available NR options, and from other cameras. The 'tricolor' patches beneath the familiar gray/black/portrait images are taken from the same test chart, and show how noise impacts upon blue, green and red areas of a scene.

ISO range noise comparison

The Pentax K-01 offers four noise reduction settings - Off, Low, Medium, High, plus Auto and Custom modes. Auto is the default setting, whice calculates and applies an 'optimized' amount of noise reduction at each ISO step. The Low, Medium and High settings apply a constant level of noise reduction across the ISO range, and in Custom mode the noise reduction setting can be defined by the user for each sensitivity setting (so you could choose 'Off' at low ISOs, 'Medium' for moderate ISOs and 'High' for ISO 12,800, for example).

The Pentax K-01's noise reduction does a remarkably good job and is pretty much on par with the best of its APS-C competition. At default settings the Pentax keeps a good balance between noise reduction and retention of fine detail up to very high ISO levels. At ISO 1600, which only a few years ago was the maximum ISO setting on many DSLRs, you can view the K-01's output at very large magnifications without noticing any noise or detail blurring, and even at 6400 noise doesn't get too intrusive in even letter-sized prints.

Raw noise (ACR 6.7, noise reduction set to zero)

Here we look at the RAW files processed through Adobe Camera Raw (in this case version 6.7). Images are brightness matched and processed with all noise reduction options set to zero. Adobe does a degree of noise reduction even when the user-controlled NR is turned off.

The amount of NR applied 'under the hood' is not high, but it does vary by camera (Adobe is attempting to normalize output across different sensors), so inevitably we are still looking at a balance of noise and noise reduction, rather than pure noise levels. However, the use of the most popular third-party RAW converter is intended to give a photographically relevant result, rather than simply comparing sensor performance in an abstract manner.

There are minor signs of noise even at the lowest sensitivity settings (remember these samples have noise reduction turned down to zero in ACR) but from ISO 400 upwards it becomes evident that the Pentax K-01 output is cleaner than some of the competition in this class, and essentially a match for its (excellent) DSLR stablemate the K-5. Some noise reduction is applied to Raw files at the K-01's top ISO sensitivities, regardless of how you have high ISO noise reduction set in the menu system, but the effect is subtle, and does not appear to have a significant impact on detail reproduction.