Here's a shot with the Canon 50/1.8, and below a similar shot (posted here before), taken with the Canon 50/1.4, different film (400 UC above, 400 Superia below), same subject, location, approximate time, but different days. This is a completely unscientific comparison. Both images were shot wide open, the 1.8 with a Canon P, and 1.4 with a Leica M7
