Canon R3 has a
24.0MP Full frame (36 x 24 mm ) sized Stacked CMOS sensor and features Digic X processor. On the other hand, Sony A7S III has a
12.0MP Full frame (35.6 x 23.8 mm ) sized BSI-CMOS sensor and features Bionz XR processor.
Canon R3's sensor provides 12MP more than Sony A7S III's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the R3 and A7S III sensor size comparison.
Sensor Size and Resolution Comparison image of Canon R3 and Sony A7S III Cameras
Canon R3 and Sony A7S III have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.
DxOMark Sensor Scores
Both Canon R3 and Sony A7S III 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, R3 has scored 96, 11 points higher than A7S III.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Canon R3
96
25.0 bits
14.7 Evs
4086 ISO
Sony A7S III
85
24.2 bits
13.4 Evs
3900 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 R3
or the
Sony A7S III ,
including hyperfocal distance.
