Both Sony NEX-5N and Sony NEX-3N have APS-C sized 16.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the NEX-5N and NEX-3N sensor size comparison.
Sensor Size and Resolution Comparison image of Sony NEX-5N and Sony NEX-3N Cameras
Sony NEX-5N and Sony NEX-3N 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
Both Sony NEX-5N and Sony NEX-3N 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, NEX-5N has scored 77, 3 points higher than NEX-3N.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony NEX-5N
77
23.6 bits
12.7 Evs
1079 ISO
Sony NEX-3N
74
22.8 bits
12.5 Evs
1067 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 NEX-5N
or the
Sony NEX-3N ,
including hyperfocal distance.
