You asked
Is the sony e 50mm f 1 8 oss sharp wide open?
I don't have sharpness test results for the Sony E 50mm f/1.8 OSS, so I can't tell you how it performs wide open. What I can tell you is that it's a stabilised prime that frames like about 75mm on APS-C, and that f/1.8 gives roughly the depth of field of f/2.7 on that sensor.
For how wide apertures affect your pictures, including focus thickness and background blur, see Portraits. If you want to compare it with other lenses, the Lenses guide explains what the f-number means for light and exposure.
Written by Claude from this site's pages.