Both Canon G12 and Pentax K200D have 10.0 MP resolution sensors but Canon G12's sensor is 1/1.7-inch (7.44 x 5.58 mm ) and Pentax K200D's sensor is APS-C (23.5 x 15.7 mm ).
Since Pentax K200D's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Canon G12.
Below you can see the G12 and K200D sensor size comparison.
As seen above, Pentax K200D has a 8.9x Larger sensor area than Canon G12. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in 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. Canon G12 and Pentax K200D sensors have been tested by DxO and the results show that K200D has a better overall score of 64, 17 points higher compared to G12's score of 47.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Canon G12 |
47 |
20.4 bits |
11.2 Evs |
161 ISO |
Pentax K200D |
64 |
22.4 bits |
11.4 Evs |
561 ISO |