Sony a5100 has a
24.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor and features Bionz X processor. On the other hand, Nikon Z8 has a
46.0MP Full frame (35.9 x 23.9 mm ) sized Stacked CMOS sensor and features Expeed 7 processor.
Nikon Z8's sensor provides 22MP more than Sony a5100'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 a5100 and Z8 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony a5100 and Nikon Z8 Cameras
As seen above, Nikon Z8 has a 2.3x Larger sensor area than Sony a5100. 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 a5100 and Nikon Z8 sensors have been tested by DxO and the results show that Z8 has a better overall score of 98, 18 points higher compared to a5100's score of 80.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony a5100
80
23.8 bits
12.7 Evs
1347 ISO
Nikon Z8
98
26.3 bits
14.2 Evs
2548 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 a5100
or the
Nikon Z8 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(APS-C versus Full frame),
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.
