So I was reading understanding exposure for the 4th time today and came across the section where he talks about pre setting the focus on your lens for a shot. now I see the numbers on the lens but not quiet understanding how it works. on my wide angle 28mm the largest is 10FT so if i'm trying to capture a huge landscape, and want everything in focus. How do I know what to set it to? He didn't go into very much detail about it in the book and I can't seem to find much on the web about it. anyone have any insight about this?