Overall Image Quality / Specifics
Overall I was very pleased with the *ist D's image quality. The *ist D's images have a very film-like appearance with both a neutral color and tonal balance. Colors are excellent, very faithful to the original scene and never look over-saturated, tonal balance is also good, images straight out of the camera are generally punchy enough to be published immediately.
One niggle however must be the soft appearance of images from the camera, this I put down to two distinct areas. Firstly the lack of pin-sharp crispness (even when deliberately stopping down the lens) reminds me of the results we got from Nikon's D100 (which uses the same sensor). Secondly it does look to me as though Pentax has chosen to take a hands-off approach when it comes to sharpening, choosing to avoid sharpening artifacts and enhanced noise by keeping the in-camera sharpening algorithms to a lower level than we are perhaps used to seeing. I would have preferred Pentax to offer more latitude of adjustment of the in-camera sharpening.
Please note that I am aware that the lenses Pentax provided for the review were not the best of their range, and especially that the 28-105 mm lens did appear to be slightly soft at the right edge. All comparison and resolution tests were carried out using the 50 mm F1.4 lens which is very sharp from F2.8 upwards (we used it mostly at F8 or F9).