It's always difficult watching actors pretending to play instruments. In this film the main four actors of the quartet almost pull it off. I shall ignore the pathetic attempt of the daughter. I understand that the main four were coached, and so some of the techniques were obviously well rehearsed (although, of course, we don't hear any of the genuine racket that they'd be producing). But I was absolutely amazed that none of the coaches stopped the actors from looking down their instruments and watching what their own fingers were doing. This practice just made them look awkward and childish, it being something a beginner would do in maybe the first few months of learning. After that period, your eyes are only ever on your music (or the conductor as well, if you're in an orchestra). What your fingers are doing is something that your brain is controlling totally sub-consciously. You aren't even aware of it most of the time. This spoiled the whole film for me as they all just looked ridiculous.