FujiFilm Finepix Z90 has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Nikon P7100 has a
10.0MP 1/1.7-inch (7.44 x 5.58 mm ) sized CCD sensor and features Expeed C2 processor.
Below you can see the Finepix Z90 and P7100 sensor size comparison.
As seen above, Nikon P7100 has a 1.5x Larger sensor area than FujiFilm Finepix Z90. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.