Canon A1100 IS has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor and features Digic 4 processor. On the other hand, Sony W810 has a
20.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Sony W810's sensor provides 8MP more than Canon A1100 IS'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 A1100 IS and W810 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon A1100 IS and Sony W810 Cameras
Canon A1100 IS and Sony W810 have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Canon A1100 IS has 65% larger pixel area compared to Sony W810, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.
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 A1100 IS
or the
Sony W810 ,
including hyperfocal distance.
