Canon 6D MII has a
26.0MP Full frame (35.9 x 24 mm ) sized CMOS sensor and features DIGIC 7 processor. On the other hand, Sony A7 IV has a
33.0MP Full frame (35.8 x 23.8 mm ) sized BSI-CMOS sensor and features Bionz XR processor.
Sony A7 IV's sensor provides 7MP more than Canon 6D MII'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.
One other difference between these two cameras that is worth mentioning is that Sony A7 IV's sensor doesn't have an anti-alias (Low-Pass) filter. Removing anti-alias filter increases the sharpness and level of detail but at the same time, it increases the chance of moiré occurring in certain scenes.
Below you can see the 6D MII and A7 IV sensor size comparison.
Sensor Size and Resolution Comparison image of Canon 6D MII and Sony A7 IV Cameras
Canon 6D MII and Sony A7 IV 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
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 6D MII and Sony A7 IV sensors have been tested by DxO and the results show that A7 IV has a better overall score of 97, 12 points higher compared to 6D MII's score of 85.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Canon 6D MII
85
24.4 bits
11.9 Evs
2862 ISO
Sony A7 IV
97
25.4 bits
14.7 Evs
3379 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 6D MII
or the
Sony A7 IV ,
including hyperfocal distance.
