Nikon D70s has a
6.0MP APS-C (23.7 x 15.5 mm ) sized CCD sensor . On the other hand, Sony A77 II has a
24.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor and features Bionz X processor.
Sony A77 II's sensor provides 18MP more than Nikon D70s's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the D70s and A77 II sensor size comparison.
Sensor Size and Resolution Comparison image of Nikon D70s and Sony A77 II Cameras
Nikon D70s and Sony A77 II 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. Nikon D70s and Sony A77 II sensors have been tested by DxO and the results show that A77 II has a better overall score of 82, 32 points higher compared to D70s's score of 50.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Nikon D70s
50
20.4 bits
10.3 Evs
529 ISO
Sony A77 II
82
24.4 bits
13.4 Evs
1013 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 D70s
or the
Sony A77 II ,
including hyperfocal distance.
