Casio EX-FC100 has a
9.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CMOS sensor . On the other hand, Canon SX280 HS has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features Digic 6 processor.
Below you can see the EX-FC100 and SX280 HS sensor size comparison.
Casio EX-FC100 and Canon SX280 HS 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 Casio EX-FC100 has 33% larger pixel area compared to Canon SX280 HS, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.