Kodak Z915 has a
10.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Kodak Easyshare M5370 has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Kodak Easyshare M5370's sensor provides 6MP more than Kodak Z915'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 Z915 and Easyshare M5370 sensor size comparison.
Kodak Z915 and Kodak Easyshare M5370 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 Kodak Z915 has 59% larger pixel area compared to Kodak Easyshare M5370, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.