Pentax K100D S has a
6.0MP APS-C (23.5 x 15.7 mm ) sized CCD sensor . On the other hand, Canon SX40 HS has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor .
Canon SX40 HS's sensor provides 6MP more than Pentax K100D S's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the K100D Super and SX40 HS sensor size comparison.
Sensor Size and Resolution Comparison image of Pentax K100D S and Canon SX40 HS Cameras
As seen above, Pentax K100D S has a 13.1x Larger sensor area than Canon SX40 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.
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
Pentax K100D S
or the
Canon SX40 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.
