Samsung NX20 has a
20.0MP APS-C (23.5 x 15.7 mm ) sized CMOS sensor . On the other hand, Nikon D7100 has a
24.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor .
One other difference between these two cameras that is worth mentioning is that Nikon D7100'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 NX20 and D7100 sensor size comparison.
Sensor Size and Resolution Comparison image of Samsung NX20 and Nikon D7100 Cameras
Samsung NX20 and Nikon D7100 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. Samsung NX20 and Nikon D7100 sensors have been tested by DxO and the results show that D7100 has a better overall score of 83, 8 points higher compared to NX20's score of 75.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Samsung NX20
75
23.4 bits
12.9 Evs
785 ISO
Nikon D7100
83
24.2 bits
13.7 Evs
1256 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
Samsung NX20
or the
Nikon D7100 ,
including hyperfocal distance.
