Both Canon 450D and Canon SX50 HS have 12.0 MP resolution sensors but Canon 450D's sensor is APS-C (22.2 x 14.8 mm ) and Canon SX50 HS's sensor is 1/2.3-inch (6.17 x 4.55 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 Canon SX50 HS.
Below you can see the 450D and SX50 HS sensor size comparison.
Sensor Size and Resolution Comparison image of Canon 450D and Canon SX50 HS Cameras
As seen above, Canon 450D has a 11.7x Larger sensor area than Canon SX50 HS. 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
Both Canon 450D and Canon SX50 HS sensors have been tested by DxoMark. DxoMark 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. Of the two cameras that we are comparing, 450D has scored 61, 14 points higher than SX50 HS.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Canon 450D
61
21.9 bits
10.8 Evs
692 ISO
Canon SX50 HS
47
20.3 bits
11.2 Evs
179 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
Canon 450D
or the
Canon SX50 HS ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(APS-C 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.
