Both Nikon D3200 and Canon SL2 have APS-C sized 24.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the D3200 and SL2 sensor size comparison.
Sensor Size and Resolution Comparison image of Nikon D3200 and Canon SL2 Cameras
Nikon D3200 and Canon SL2 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 Nikon D3200 and Canon SL2 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, D3200 has scored 81, 2 points higher than SL2.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Nikon D3200
81
24.1 bits
13.2 Evs
1131 ISO
Canon SL2
79
23.6 bits
13.4 Evs
1041 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
Nikon D3200
or the
Canon SL2 ,
including hyperfocal distance.
