Kodak Astro Zoom AZ651 has a 21.0MP 1/2.3 (6.17 x 4.55 mm ) sized CMOS sensor . On the other hand, Fujifilm HS50 EXR has a 16.0MP 1/2-inch (6.4 x 4.8 mm ) sized EXRCMOS sensor and features EXR Processor II processor.
Kodak Astro Zoom AZ651's sensor provides 5MP more than Fujifilm HS50 EXR'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 Astro Zoom AZ651 and HS50 EXR sensor size comparison.
Kodak Astro Zoom AZ651 and Fujifilm HS50 EXR have almost the same sensor size so none of them has any significant advantage over other in providing control over depth of field when used with same focal length and aperture.