Question about DOF (I think)

[Gamb]

Went to the beach this past weekend and was fiddling with the camera using my dog as a subject. I was working with my flash b/c the dog and i were in the shade on the deck and the beach and ocean were behind us in the bright sunshine. I was showing some pictures to a buddy of mine today and he commented that in the photo below he thought the palm trees in the background would be in better focus because I was at F/11. Well.. it got me curious also so I thought I'd throw the question out here

Why aren't the palm trees and background in better focus at F/11?

http://gambrell.smugmug.com/Animals/Gambrell-Family-Pictures/IMG4080/1005339379_7gTjV-L.jpg

[canongrip]

Smaller aperture will giver bigger DOF. But not infinit DOF!

The focus point is very close to camera.
It's normal that a few meters away, the image will stay out of focus, regardless the aperture number.

I suggest that you try the same scenario with different aperture sizes to understand the implicants of DOF with two 'subjects' so far away one from another.

[gonzogolf]

It comes down to how close you are to the primary subject. Try this DOF calculator. http://www.dofmaster.com/dofjs.html Enter your aperture and lens then play with the distance to subject. At 4 feet (just guessing) your DOF is about 3 feet. If you changed that to 15 feet your DOF goes to infinite.

[Gamb]

Ok. I get it. It's because of how close to the dog I was standing. The patio is small, not much room for me to backup there. Thanks