There are times when you can not avoid some obstructions the way of a clean composition, Usually it is best to walk around a little and it is surprising how easy it can be to avoid signs, lampposts etc. Other times it does seem to be impossible to avoid distracting objects in a good composition. You might avoid that sign but then a tree or parked car pops into frame.
In such cases it is handy to have a context sensitive easer, (or alternatively a cloning tool). There is a really neat context toll in OnOne 10 Enhance called perfect Eraser. It works best if you just remove a few sections at a time, but it does and amazing job with a relatively few strokes. Photoshop has a similar tool and lightroom has a liner clone tool, similar to the spot removal tool and make need a few more corrections. The results can make a significant to your compositiom
