I did not know about these useful techniques until now. This comes in handy for tricky lighting situations. I let my camera autofocus, I thought that was good enough. The technology in the camera should be smarter than I am, so I let it do its thing. However, like all technology, it is good only to a certain point. Beyond that point, if you can not get the image you desire, then the tech has failed and you must take control of the settings manually.