Pentax P70 has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Samsung WB2200F has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor .
Below you can see the P70 and WB2200F sensor size comparison.
Pentax P70 and Samsung WB2200F 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 Pentax P70 has 32% larger pixel area compared to Samsung WB2200F, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.