Both Nikon D7000 and Nikon D4s have 16.0 MP resolution sensors but Nikon D7000's sensor is APS-C (23.6 x 15.7 mm ) and Nikon D4s's sensor is Full frame (36 x 23.9 mm ).
Since Nikon D4s'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 Nikon D7000.
Below you can see the D7000 and D4s sensor size comparison.
Sensor Size and Resolution Comparison image of Nikon D7000 and Nikon D4s Cameras
As seen above, Nikon D4s has a 2.3x Larger sensor area than Nikon D7000. 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
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. Nikon D7000 and Nikon D4s sensors have been tested by DxO and the results show that D4s has a better overall score of 89, 9 points higher compared to D7000's score of 80.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Nikon D7000
80
23.5 bits
13.9 Evs
1167 ISO
Nikon D4s
89
24.4 bits
13.3 Evs
3074 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 D7000
or the
Nikon D4s ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(APS-C versus Full frame),
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.
