Both Panasonic GF1 and Olympus 9000 have 12.0 MP resolution sensors but Panasonic GF1's sensor is Four Thirds (17.3 x 13 mm ) and Olympus 9000's sensor is 1/2.3-inch (6.08 x 4.56 mm ).
Since Panasonic GF1'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 Olympus 9000.
Below you can see the GF1 and 9000 sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic GF1 and Olympus 9000 Cameras
As seen above, Panasonic GF1 has a 8.1x Larger sensor area than Olympus 9000. 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.
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 GF1
or the
Olympus 9000 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(Four Thirds versus 1/2.3-inch),
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.
