Both Sony A65 and Canon 77D have APS-C sized 24.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the A65 and 77D sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A65 and Canon 77D Cameras
As seen above, Sony A65 has a 1.1x Larger sensor area than Canon 77D. 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
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 A65 and Canon 77D sensors have been tested by DxO and the results show that 77D has a better overall score of 78, 4 points higher compared to A65's score of 74.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony A65
74
23.4 bits
12.6 Evs
717 ISO
Canon 77D
78
23.6 bits
13.3 Evs
971 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 A65
or the
Canon 77D ,
including hyperfocal distance.
