You can use this for zone focusing for street photography, for example. If I set my little Voigtländer 35mm f/2.5 Color Skopar to a focus distance of 3m and a lens aperture of f/8, I can see that ...

Additionally, the depth-of-field is just so shallow – even with the smaller sized sensors – you need the camera to be on a tripod so that you can better concentrate on getting the focus ...