You asked
Is the canon ef 35mm f 2 is usm sharp wide open?
I don't have sharpness test results for the Canon EF 35mm f/2 IS USM, so I can't tell you how it performs at f/2. What I can tell you is that it's a prime for full frame Canon EF bodies, it's stabilised, and it gives about the depth of field of f/3.2 on APS-C.
If you want to know how a wide aperture affects sharpness and background blur, the Lenses guide explains how f-numbers work. For portraits, where wide apertures matter most, see Portraits.
Written by Claude from this site's pages.