Samsung HZ15W has a
12.0MP 1/2.3-inch (6.08 x 4.56 mm ) sized CCD sensor . On the other hand, Samsung ST150F has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Below you can see the HZ15W and ST150F sensor size comparison.
Sensor Size and Resolution Comparison image of Samsung HZ15W and Samsung ST150F Cameras
Samsung HZ15W and Samsung ST150F 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
Samsung HZ15W
or the
Samsung ST150F ,
including hyperfocal distance.