Sony H50 has a
9.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Casio EX-Z90 has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor and features Digic 4 processor.
Below you can see the H50 and EX-Z90 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony H50 and Casio EX-Z90 Cameras
Sony H50 and Casio EX-Z90 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 Sony H50 has 33% larger pixel area compared to Casio EX-Z90, 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
Sony H50
or the
Casio EX-Z90 ,
including hyperfocal distance.