Fujifilm X100 has a
12.0MP APS-C (23.6 x 15.8 mm ) sized CMOS sensor and features EXR processor. On the other hand, Ricoh GR has a
16.0MP APS-C (23.7 x 15.7 mm ) sized CMOS sensor .
Another difference between these two cameras is that Fujifilm X100's sensor lacks 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 X100 and GR sensor size comparison.
Sensor Size and Resolution Comparison image of Fujifilm X100 and Ricoh GR Cameras
Fujifilm X100 and Ricoh GR 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. Fujifilm X100 and Ricoh GR sensors have been tested by DxO and the results show that GR has a better overall score of 78, 5 points higher compared to X100's score of 73.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Fujifilm X100
73
22.9 bits
12.4 Evs
1001 ISO
Ricoh GR
78
23.6 bits
13.5 Evs
972 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
Fujifilm X100
or the
Ricoh GR ,
including hyperfocal distance.