Both Panasonic FX580 and Canon 450D have 12.0 MP resolution sensors but Panasonic FX580's sensor is 1/2.3-inch (6.08 x 4.56 mm ) and Canon 450D's sensor is APS-C (22.2 x 14.8 mm ).
Since Canon 450D'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 FX580.
Below you can see the FX580 and 450D sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic FX580 and Canon 450D Cameras
As seen above, Canon 450D has a 11.9x Larger sensor area than Panasonic FX580. 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 FX580
or the
Canon 450D ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/2.3-inch versus APS-C),
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.
