Just below, the Sony Alpha A200 is compared to the Pentax K10D and the Pentax K20D. Images below are all 100% scale crops taken from full-resolution images at each ISO setting from their respective camera. All three cameras were set to produce their highest quality JPEG images. Exposures were taken using the default metering system in aperture-priority mode, automatic white-balance and set ISO sensitivity.

Our new CFL lighting posed quite a challenge to these cameras. Being neither incandescent nor fluorescent, in terms of color temperature, automatic white-balance from all three DSLRs produced different results. The most correct one is actually the Sony Alpha A200, while the least correct one is the Pentax K10D. Although the K20D falls somewhere in between, it still left a relatively strong cast under CFL lighting. It is probably time for manufacturers to add a CFL preset white-balance.

The Sony Alpha A200 manages to keep noise relatively low up to ISO 1600. On the A200, ISO 100 shows the most details and is noise-free. Interestingly, the best crop below comes from the 14.6 megapixels K20D at ISO 200 but the Alpha A200's ISO 100 comes in second. As ISO increases on the A200, noise-reduction slowly increases to reduce the appearance of image noise. It works very well and - for once - has a small gradual effect on image details. At ISO 800 we can see that the fabric pattern is nearly gone but the print is still clear and detailed. At ISO 1600, noise dominates the noise-reduction but the image is still highly recognizable. At ISO 3200, the A200 shows moderate image noise and loss of details. Overall, the A200 shows excellent control over image noise.

As far as the comparison goes, we can see that Pentax, with the K10D and K20D, likes to keep more image details and applies less noise-reduction. The result is that the Sony A200 produces images that appear cleaner at all ISO settings but at the expense of some details. All images are equally usable for prints up to ISO 1600. At ISO 3200, the Sony would the nicest small print.

Another difference between these cameras is the exposure. It appears that the Sony A200 is more sensitive to light. Looking at the exposure values, the Sony Alpha consistently produced a brighter image while near always choosing a shorter exposure time. Given that ISO and aperture were fixed, the only variable left is the contrast curve which probably contributes to some of the difference in brightness.