First lens upgrade : 70-300mm f/4-5.6

This also has to do with distances and how a zoom lens "Compresses" the image. So when you are shooting something at say f/5.6 that is a foot or so away your depth of field is much narrower then if you are shooting something that is much further away.

Unfortunately this lens doesn't have the scale on it like older lenses so. This would show you your "Focus" range depending on your zoom and your f-stop.

My eagle was shot at f/5.6 but he was about 10 feet away from me. If I shot the same thing with him closer then I wouldn't have as much of him in focus as I do.

Does this make sense?

Yes it does, thanks for the information (and msowsun). I will keep that in mind when I go to shoot some more pictures tomorrow.

this is a good link to help you understand the DOF, and how each aspect affects it
http://www.dofmaster.c​om/dofjs.html