Dave, thanks for posting all the samples. So do I have this right? The smaller the aperture, the greater the depth of field, which would have improved my Mt. Rushmore photo. And the smaller the aperture, the larger the f-stop: f2.8 is large (wide open to let in lots of light) while f32 is very small.
Now I need to figure out how to manually control my aperture while allowing the camera and lens to work the rest of its magic.