Sony A9 III has a
24.6MP Full frame (35.6 x 23.8 mm ) sized Global Shutter sensor and features BIONZ XR processor. On the other hand, Nikon D500 has a
21.0MP APS-C (23.5 x 15.7 mm ) sized CMOS sensor and features Expeed 5 processor.
Another similarity between these two cameras is that both Nikon D500 and Sony A9 III sensors lack anti-alias (Low-Pass) filters. 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 A9 Mark III and D500 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A9 III and Nikon D500 Cameras
As seen above, Sony A9 III has a 2.3x Larger sensor area than Nikon D500. 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 A9 III and Nikon D500 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, A9 Mark III has scored 87, 3 points higher than D500.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony A9 III
87
24.1 bits
13.0 Evs
3224 ISO
Nikon D500
84
24.1 bits
14.0 Evs
1324 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 A9 III
or the
Nikon D500 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(Full frame versus APS-C),
so compare them at the same framing rather than the same focal length.
Put the same focal length on the smaller sensor and it will show less depth of
field, not more, because it also crops tighter. The calculator shows the
full frame equivalent focal length for each body so you can match the framing.
