Sony HX350 has a 20.0MP (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features BIONZ X processor. You can shoot at maximum resolution of 5184 x 3456 pixels with aspect ratios of 1:1, 4:3, 3:2 and 16:9. HX350 has a native ISO range of 80 - 3200 which can be boosted to 12800 but unfortunately, Sony HX350 doesn't have RAW file support. If you need a DSLR-Like camera with a RAW support, consider or in the same price range.
Sony HX350 is not the highest resolution Small Sensor camera. Canon SX740 HS with its 21.0MP sensor is leading in this class. Check the comparison of Sony HX350 vs Canon SX740 HS or take a look at Highest resolution Bridge cameras list.
Let's look at how the size of the Sony HX350's sensor compares with other standard sensor sizes.
Comparison image of Sony HX350 Sensor Size with other standard sensors
Sensor size is what determines the circle of confusion, and therefore how much
depth of field Sony HX350 gives you at any given aperture.
You can
calculate
the exact depth of field for the Sony HX350
at any focal length, aperture and subject distance, including the hyperfocal distance
for landscapes and how close you can get before the focus zone becomes too thin.