The italian Leica Lab blog interviewed me about the 21mm focal lenght in Street Photography:
" Of course a wide angle means also being able to show much more of a scenery. Mixing it with people is really a great deal for strong images where people and landscape are both important in your frame. With a 21mm, you can get pretty all you got in front of your lens, while it doesn’t distort as much as the real ultra wide angles. "
Here is the full interview: 21mm Street Photography