Panasonic FX48 has a 12.0MP 1/2.3-inch (6.08 x 4.56 mm ) sized CCD sensor . On the other hand, Sigma DP2s has a 5.0MP APS-C (20.7 x 13.8 mm ) sized CMOS (Foveon X3) sensor and features True II processor.
Panasonic FX48's sensor provides 7MP more than Sigma DP2s'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 FX48 and DP2s sensor size comparison.
![Panasonic FX48 vs Sigma DP2s Sensor Size Comparison]()
Sensor Size and Resolution Comparison image of Panasonic FX48 and Sigma DP2s Cameras
As seen above, Sigma DP2s has a 10.3x Larger sensor area than Panasonic FX48. 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.