Both Panasonic FZ70 and Olympus E-PL7 have 16.0 MP resolution sensors but Panasonic FZ70's sensor is 1/2.3-inch (6.17 x 4.55 mm ) and Olympus E-PL7's sensor is Four Thirds (17.3 x 13 mm ).
Since Olympus E-PL7'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 Panasonic FZ70.
Below you can see the FZ70 and E-PL7 sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic FZ70 and Olympus E-PL7 Cameras
As seen above, Olympus E-PL7 has a 8.0x Larger sensor area than Panasonic FZ70. 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. Panasonic FZ70 and Olympus E-PL7 sensors have been tested by DxO and the results show that E-PL7 has a better overall score of 72, 31 points higher compared to FZ70's score of 41.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Panasonic FZ70
41
19.4 bits
10.8 Evs
171 ISO
Olympus E-PL7
72
22.7 bits
12.4 Evs
873 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
Panasonic FZ70
or the
Olympus E-PL7 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/2.3-inch versus Four Thirds),
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.
