We ought to be grateful for myriad of options in customizing the Preview/Fn/AE-AF Lock buttons. But as you all know, DSLR also throws a number of tasks at you never seen with film cameras. There is a lot to look at before snapping off shots.
I was wondering how others dial in a function for the DOF button? Mine is on default, stopping down the lens when pressed. I find that I don't take advantage of it and would like to configure something that would speed up or enhance my shots. FV Lock, Flash Off, Bracketing?
Of course this button would work along with the Fn and AE-AF/Lock. I have those set to Spot Meter and Back Button Focus (AF-On). This last setting has made sweeping changes in the way I shoot.