I know that by going into the menu of my Nikon camera (the D750) I can place a grid in my viewfinder. What's kind of frustrating, though, is that the lines are not placed at 1/3 points in accordance with the popular "rule of thirds" composition principle -- even my Samsung Galaxy phone does that! They seem more like 80% or so. There isn't any way to change the placement of the lines, is there?
