Both Sony A200 and Sony A300 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 A200 and A300 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A200 and Sony A300 Cameras
Sony A200 and Sony A300 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. Sony A200 and Sony A300 sensors have been tested by DxO and the results show that A300 has a better overall score of 64, 1 points higher compared to A200's score of 63.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony A200
63
22.3 bits
11.3 Evs
521 ISO
Sony A300
64
22.5 bits
11.4 Evs
538 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
Sony A200
or the
Sony A300 ,
including hyperfocal distance.
