Pictures produced by the Pentax K-01 are rich in detail and vibrant in colour, without appearing unnatural, and it it more than capable of producing stunning results with the right subject, in the right conditions.
Its multi-segment metering is consistent, but often tends to underexpose, even when scenes only have small bright areas in them. But at least the highlights are preserved, High-contrast scenes nearly always fool the multi-segment metering, so having three stops of exposure compensation either side of the metered value at your disposal is handy.
Meanwhile the auto white balance system does a decent job of correcting colour casts under artificial lighting, leaving a warm cast. However, under overcast conditions images can be left looking quite cold, with a noticeable blue cast being produced in the image.
Plenty of white balance presets are provided, which correct casts adequately, and a custom white balance function is there for times when the colour lighting is tricky to compensate for.
Because the sensor fitted to the Pentax K-01 CSC is the same unit found in the Pentax K-5 DSLR, noise control at high sensitivities is pretty much the same. This is a good thing, because the Pentax K-5 performs extremely well at high sensitivities.
There is no significant image degradation due to noise until ISO 1600, where a little noise can be seen in midtones, and a little softening due to noise reduction can be seen on in-camera JPEGs. Even so, the effects of noise are only very slight, and even pictures taken at ISO 6400 should be printable to around A4 (US letter) size.
Beyond that, noise starts to become much more prominent, although images taken at ISO 25600 still have accurate colours, and should be more than adequate for sharing at low resolutions on the web.
Raw images taken at sensitivities of ISO 3200 and above display much higher levels of noise, but they also contain much more detail. A combination of careful noise reduction and sharpening in post processing can still yield good results though.
Auto focus speed and the (lack of) responsiveness of the shutter are both weak points of this camera. Even in good light, with a high-contrast subject, the autofocus system takes at least the best part of a second to lock onto a subject. In low light conditions and with low contrast subjects, a frustrating wait while the camera tracks back and forth attempting to find a lock is the norm.
Luckily, manual focusing is quite easy, since pressing the OK button magnifies the centre section of the image on the screen to improve accuracy.
But the delay between pressing the shutter release, once the lens is focused, and the shutter firing can be quite noticeable, especially when taking pictures of moving subjects. This can be very frustrating, since fleeting moments are easily missed, and even people's expressions may have changed during the delay.