If you’re serious about architectural photography, the easiest way to avoid converging verticals is by investing in a tilt-shift lens like the Canon TS-E 24mm f/3.5L II, Nikon 24mm f/3.5D ED PC-E or Samyang T-S 24mm f/3.5. With these lenses you can raise the front end to include the top of a building, instead of tilting the camera backwards. The ‘miniaturisation’ effect you get using the tilt function to minimise depth-of-field rather than maximise it also works well on modern architecture.