I am having a little difficulty grasping the concept of depth of field- what's sharp and what's not. I understand that an aperture of say f4 creates a shallow depth of field. An aperture of say f11-f16 would create a greater depth of field. But my confusion comes in here. Taking a landscape shot I want as much of the foreground, middle and distance to be in focus. What should I focus on? If I focus on something in say the middle, a tree for example wouldn't that make everything else out of focus? Would the best method be to shoot in manual? My eyes are not terribly good, so could I set the camera to auto and then switch over. I have attached an image, but it still leaves me pondering the question of what will be in focus if I focus on the tree.