Canon 1Ds MII has a
17.0MP Full frame (36 x 24 mm ) sized CMOS sensor . On the other hand, Sigma fp L has a
61.0MP Full frame (36 x 24 mm ) sized BSI-CMOS sensor .
Sigma fp L's sensor provides 44MP more than Canon 1Ds MII'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 1Ds MII and fp L sensor size comparison.
Sensor Size and Resolution Comparison image of Canon 1Ds MII and Sigma fp L Cameras
Canon 1Ds MII and Sigma fp L 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 1Ds MII has 262% larger pixel area compared to Sigma fp L, 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 1Ds MII
or the
Sigma fp L ,
including hyperfocal distance.
