Both Sony RX100 and Samsung NX30 have 20.0 MP resolution sensors but Sony RX100's sensor is 1-inch (13.2 x 8.8 mm ) and Samsung NX30's sensor is APS-C (23.5 x 15.7 mm ).
Since Samsung NX30's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Sony RX100.
Below you can see the RX100 and NX30 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony RX100 and Samsung NX30 Cameras
As seen above, Samsung NX30 has a 3.2x Larger sensor area than Sony RX100. 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 RX100 and Samsung NX30 sensors have been tested by DxO and the results show that NX30 has a better overall score of 77, 11 points higher compared to RX100's score of 66.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony RX100
66
22.6 bits
12.4 Evs
390 ISO
Samsung NX30
77
23.5 bits
12.4 Evs
1014 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 RX100
or the
Samsung NX30 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1-inch 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.
