What is the absolute sharpest portrait prime I can get for my 90D that actually works because I am honestly so fed up with my current setup. Ive been trying to make the nifty fifty 50mm f1.8 work for months but the focus is just so hit or miss on this body and honestly the images look soft even when I nail it and its driving me crazy. I have a big family wedding coming up in three weeks in Bend and I really dont want to show up with gear I cant trust to deliver those crisp shots everyone expects.

Im looking for something that just stays sharp corner to corner and handles the 32.5MP sensor on the 90D because apparently this sensor is really picky with glass or so Ive read on some blogs. My budget is probably around $700 maybe $800 if I stretch it but I really need it to arrive before the 15th. I was looking at the Sigma 50mm Art or maybe an 85mm but Im worried about the crop factor making it too tight since Ill be indoors mostly. Is the Canon 85mm f1.8 any better or am I just gonna run into the same soft focus issues again? I just want something that makes me actually like my camera again because right now Im ready to just sell the whole kit...