Sony A57 has a
16.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor . On the other hand, Canon 650D has a
18.0MP APS-C (22.3 x 14.9 mm ) sized CMOS sensor and features Digic 5 processor.
Below you can see the A57 and 650D sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A57 and Canon 650D Cameras
As seen above, Sony A57 has a 1.1x Larger sensor area than Canon 650D. 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
Both Sony A57 and Canon 650D 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, A57 has scored 75, 13 points higher than 650D.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony A57
75
23.4 bits
13.0 Evs
785 ISO
Canon 650D
62
21.7 bits
11.2 Evs
722 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 A57
or the
Canon 650D ,
including hyperfocal distance.
