Kodak C140 has a
8.0MP 1/2.5-inch (5.744 x 4.308 mm ) sized CCD sensor . On the other hand, Kodak M550 has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Below you can see the C140 and M550 sensor size comparison.
As seen above, Kodak M550 has a 1.1x Larger sensor area than Kodak C140. 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.