Both Canon M3 and Sony NEX-7 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 M3 and NEX-7 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon M3 and Sony NEX-7 Cameras
As seen above, Sony NEX-7 has a 1.1x Larger sensor area than Canon M3. 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. Canon M3 and Sony NEX-7 sensors have been tested by DxO and the results show that NEX-7 has a better overall score of 81, 9 points higher compared to M3's score of 72.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Canon M3
72
22.8 bits
11.8 Evs
1169 ISO
Sony NEX-7
81
24.1 bits
13.4 Evs
1016 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 M3
or the
Sony NEX-7 ,
including hyperfocal distance.
