You can see a couple of the previously mentioned tips in this video.
I find clingfilm (plastic wrap) and rice work best for blind baking. It really helps with defined corners. For conventional lining, try folding the pastry outside the ring to combat shrinkage. Then, for clean edges, use a microplane. All three are employed here.
With a bit of practice you'll be surprised how straightforward it is. This lemon tart looks alright, and I ain't no pro.
For the fully baked, empty shells you've posted, the 'secret' is really just well made pâté sucrée that's rested and doesn't shrink much, combined with good lining technique and a bit of post-bake shaving to neaten up any rough edges.
