When you aim your camera up, you get converging verticals – like this:
You can use an expensive tilt-shift lens to fix that.
But there is an easier way: in the Lightroom “Develop” module, find “Lens Corrections”, go to the “Manual” tab, and you see this:
Pull “Vertical” to the left a little (as I did above), and you get this:
The verticals have been disciplined!
All you now need to do is crop off the edges (see bottom left).
Simple – takes only a second. Lightroom rocks!