Noise
JPEG images from the Pentax Prime III processor can have multiple issues which cause a lack of detail in images such as clipping in colour channels and in-camera noise reduction. However, it’s possible to control noise and achieve detailed images shooting in raw and post-processing.
At ISO sensitivities between ISO 100-800, there is some luminance noise present in the raw files but it’s very slight and only obvious at ISO 1,600 and above. I would happily use this camera right up to 6,400 without worrying too much about colour or luminance noise, but thereafter I would take measures to keep it lower.
Below are 100% crops from our test scene across the full range of ISO sensitivities.
Pentax K-3 II noise – ISO 100
Pentax K-3 II noise – ISO 200
Pentax K-3 II noise – ISO 400
Pentax K-3 II noise – ISO 800
Pentax K-3 II noise – ISO 1600
Pentax K-3 II noise – ISO 3200
Pentax K-3 II noise – ISO 6400
Pentax K-3 II noise – ISO 12,800
Pentax K-3 II noise – ISO 25,600
Pentax K-3 II noise – ISO 51,200
