Canon S90 has a
10.0MP 1/1.7-inch (7.44 x 5.58 mm ) sized CCD sensor and features Digic 4 processor. On the other hand, Samsung NX20 has a
20.0MP APS-C (23.5 x 15.7 mm ) sized CMOS sensor .
Samsung NX20's sensor provides 10MP more than Canon S90'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 S90 and NX20 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon S90 and Samsung NX20 Cameras
As seen above, Samsung NX20 has a 8.9x Larger sensor area than Canon S90. 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. Canon S90 and Samsung NX20 sensors have been tested by DxO and the results show that NX20 has a better overall score of 75, 29 points higher compared to S90's score of 46.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Canon S90
46
20.2 bits
11.0 Evs
185 ISO
Samsung NX20
75
23.4 bits
12.9 Evs
785 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 S90
or the
Samsung NX20 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/1.7-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.
