Both Pentax K200D and Pentax K10D have APS-C sized 10.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the K200D and K10D sensor size comparison.
Sensor Size and Resolution Comparison image of Pentax K200D and Pentax K10D Cameras
Pentax K200D and Pentax K10D have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture.
DxOMark Sensor Scores
DxOMark is a benchmark that scientifically assesses image quality of camera sensors. It scores camera sensors for color depth (DXO Portrait), dynamic range (DXO Landscape) and low-light sensitivity (DXO Sports), and also gives them an overall score. Pentax K200D and Pentax K10D sensors have been tested by DxO and the results show that K10D has a better overall score of 66, 2 points higher compared to K200D's score of 64.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Pentax K200D
64
22.4 bits
11.4 Evs
561 ISO
Pentax K10D
66
22.7 bits
11.6 Evs
522 ISO
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Pentax K200D
or the
Pentax K10D ,
including hyperfocal distance.
