Both Sony A290 and Sony A390 have APS-C sized 14.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the A290 and A390 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A290 and Sony A390 Cameras
Sony A290 and Sony A390 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
At Camera Decision, we also look at Dxo Mark sensors when available as we think it is a good indicator of image quality.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony A290
66
22.6 bits
11.5 Evs
615 ISO
Sony A390
66
22.5 bits
11.5 Evs
607 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 A290
or the
Sony A390 ,
including hyperfocal distance.
