Both Nikon D200 and Nikon D3000 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 D200 and D3000 sensor size comparison.
Sensor Size and Resolution Comparison image of Nikon D200 and Nikon D3000 Cameras
Nikon D200 and Nikon D3000 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
Both Nikon D200 and Nikon D3000 sensors have been tested by DxoMark. DxoMark 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. Of the two cameras that we are comparing, D200 has scored 64, 2 points higher than D3000.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Nikon D200
64
22.3 bits
11.5 Evs
583 ISO
Nikon D3000
62
22.3 bits
11.1 Evs
563 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
Nikon D200
or the
Nikon D3000 ,
including hyperfocal distance.
