f/11 is the sweet spot for several lenses I have and used to have. I did have a Canon 18-55 at one time it is was very nice at f/11. My 60mm macro lens is sweetest there. I have a 10-22 lens that reaches its optimum at f/7.1 and starts to diffract at f/8 and beyond with my Canon 20d sensor. The light comes in very angled with that short focal length lens. The thing is, at 10mm I can get everything from about 1.25' to inf in focus using hyperfocal distance of about 2.5'. You can find that chart here--> DOF Chart

I tried that with this B&W image at 10mm and f/7.1 but the far mountains look a little soft which does not hurt this one but my focus must have been closer with a nice sharp foreground but missed infinity a bit. A self portrait like this is always harder to accomplish. It can be done though.