Fujifilm S4500 has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Nikon A1000 has a
16.0MP 1/2.3 (6.17 x 4.55 mm ) sized BSI-CMOS sensor .
Below you can see the S4500 and A1000 sensor size comparison.
Sensor Size and Resolution Comparison image of Fujifilm S4500 and Nikon A1000 Cameras
Fujifilm S4500 and Nikon A1000 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 Fujifilm S4500 has 15% larger pixel area compared to Nikon A1000, 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
Fujifilm S4500
or the
Nikon A1000 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/2.3-inch versus 1/2.3),
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.