I mainly take pictures/portraits of my two boys. I am using a canon 40D with a 50 mm f/1.4 primarily as well as a 28-135mm. The problem I sometimes have is getting both boys in focus when using aperture priority? Where is the best place to place the focus for them to both be sharp and in focus? Is it primarily dependent on the aperture setting? What if I want a narrow DOF (f/1.8-2.2). Is it possible to get the boys in focus and still create nice bokeh? Thanks in advance for comments and suggestions.