it's the unofficial rallying cry of these boards, as decreed in mousefest by gary. when asked about the secret of his success, the great photographer Alfred Eisenstaedt said “f/8 and be thereâ€
Aha. Rolleiflex... "They never saw me clicking away. For the kind of photography I do, one has to be very unobtrusive and to blend in with the crowd." Try that with the chimping crowd nowadays. That can explain why I've heard f/8 is the sweet spot in general, but it really does matter with lens focal length/sensor(film) size, etc. etc. distance to subject... plus the lens itself!