Pentax K-r High ISO NR
Pentax K-r Noise Reduction
The Pentax K-r offers four high-ISO noise-reduction levels, plus an auto setting that selects the level for you, and a custom setting that lets you pick the amount of NR for each ISO level. The Pentax K-r therefore gives the user outstanding flexibility in choosing how to make the trade-off between subject detail and noise levels in JPEGs. Settings available "Off ", "Low", "Medium", "High", "Auto" (the default), and "Custom". Since NR can already be applied at base ISO, we've included crops starting from ISO 100.
The crops below show the effects of the Pentax K-r's four levels of noise reduction available, under the studio HMI lighting we use to simulate daylight. 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.
To our eyes, the "Medium" level of noise reduction strikes an okay balance between noise and subtle subject detail, although the red fabric swatch presents a challenge even at base ISO on the Pentax K-r. Cranking the noise reduction setting up to "Strong" 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 even at ISO 100 (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 "Off" noise reduction setting (which obviously doesn't disable all noise reduction) leaves more noise in the image, but also leaves a lot more subject detail: 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 RAW files.