I'm referring to both M's eyes and to the aperture at which I shot this photo. Don't think too hard, but the aperture refers to the opening that lets light into the camera. Shooting wide open results in a very small area of sharp focus. I shot this photo with my new Tamron 28-75mm lens at f/2.8. I can't believe how incredibly sharp it is, even wide open! Wow, I think I'm gonna like this lens.