Both Canon S95 and Canon G12 have 1/1.7-inch sized 10.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the S95 and G12 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon S95 and Canon G12 Cameras
Canon S95 and Canon G12 have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture.
DxOMark Sensor Scores
At Camera Decision, we also look at Dxo Mark sensors when available as we think it is a good indicator of image quality.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Canon S95
47
20.4 bits
11.3 Evs
153 ISO
Canon G12
47
20.4 bits
11.2 Evs
161 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 S95
or the
Canon G12 ,
including hyperfocal distance.
