Sony A850 has a
25.0MP Full frame (35.9 x 24 mm ) sized CMOS sensor and features Bionz processor. On the other hand, Sony A7 has a
24.0MP Full frame (35.8 x 23.9 mm ) sized CMOS sensor and features Bionz X processor.
Below you can see the A850 and A7 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A850 and Sony A7 Cameras
Sony A850 and Sony A7 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. Sony A850 and Sony A7 sensors have been tested by DxO and the results show that A7 has a better overall score of 90, 11 points higher compared to A850's score of 79.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Sony A850
79
23.8 bits
12.2 Evs
1415 ISO
Sony A7
90
24.8 bits
14.2 Evs
2248 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 A850
or the
Sony A7 ,
including hyperfocal distance.
