Both Kodak AZ255 and Pentax RZ18 have 16.0 MP resolution sensors but Kodak AZ255's sensor is 1/2.3 (6.17 x 4.55 mm ) and Pentax RZ18's sensor is 1/2.3-inch (6.08 x 4.56 mm ).
Since Kodak AZ255's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Pentax RZ18.
Below you can see the AZ255 and RZ18 sensor size comparison.
Sensor Size and Resolution Comparison image of Kodak AZ255 and Pentax RZ18 Cameras
Kodak AZ255 and Pentax RZ18 have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.
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
Kodak AZ255
or the
Pentax RZ18 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/2.3 versus 1/2.3-inch),
so compare them at the same framing rather than the same focal length.
Put the same focal length on the smaller sensor and it will show less depth of
field, not more, because it also crops tighter. The calculator shows the
full frame equivalent focal length for each body so you can match the framing.
