Both Ricoh GR II and Olympus E-M5 II have 16.0 MP resolution sensors but Ricoh GR II's sensor is APS-C (23.7 x 15.7 mm ) and Olympus E-M5 II's sensor is Four Thirds (17.3 x 13 mm ).
Since Ricoh GR II'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 Olympus E-M5 II.
Below you can see the GR II and E-M5 Mark II sensor size comparison.
Sensor Size and Resolution Comparison image of Ricoh GR II and Olympus E-M5 II Cameras
As seen above, Ricoh GR II has a 1.7x Larger sensor area than Olympus E-M5 II. 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 Ricoh GR II and Olympus E-M5 II 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, GR II has scored 80, 7 points higher than E-M5 Mark II.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Ricoh GR II
80
23.6 bits
13.7 Evs
1078 ISO
Olympus E-M5 II
73
23.0 bits
12.4 Evs
896 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
Ricoh GR II
or the
Olympus E-M5 II ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(APS-C versus Four Thirds),
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.
