Sony WX5 has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features Bionz processor. On the other hand, Nikon S810c has a
16.0MP 1/2.3' (6.17 x 4.55 mm ) sized BSI-CMOS sensor .
Below you can see the WX5 and S810c sensor size comparison.
Sony WX5 and Nikon S810c 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 Sony WX5 has 32% larger pixel area compared to Nikon S810c, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.