Sony RX100 III has a
20.0MP 1″ (13.2 x 8.8 mm ) sized BSI-CMOS sensor and features Bionz X processor. On the other hand, Sony A700 has a
12.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor .
Sony RX100 III's sensor provides 8MP more than Sony A700'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 RX100 III and A700 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony RX100 III and Sony A700 Cameras
As seen above, Sony A700 has a 3.2x Larger sensor area than Sony RX100 III. 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 RX100 III and Sony A700 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, RX100 III has scored 67, 1 points higher than A700.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony RX100 III
67
22.4 bits
12.3 Evs
495 ISO
Sony A700
66
22.3 bits
11.9 Evs
581 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 III
or the
Sony A700 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1″ 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.
