Canon 550D has a
18.0MP APS-C (22.3 x 14.9 mm ) sized CMOS sensor and features Digic 4 processor. On the other hand, Sony A390 has a
14.0MP APS-C (23.5 x 15.7 mm ) sized CCD sensor and features Bionz processor.
Below you can see the 550D and A390 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon 550D and Sony A390 Cameras
As seen above, Sony A390 has a 1.1x Larger sensor area than Canon 550D. 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
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
Canon 550D
66
22.0 bits
11.6 Evs
807 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
Canon 550D
or the
Sony A390 ,
including hyperfocal distance.
