When Bob enters the diner he picks up the can and puts it down but in the next scene he is holding it again and in the next scene it is on the counter again.
The position of Becker's pillow as he chews out the red-headed doctor.
A man drops a coin in Bob's fake charity can. Becker immediately grabs it from Bob, reads the label, and when he tosses it back to Bob it spins end over end and there is no coin in the can.
Jake calls Becker after he falls asleep on a train and winds up in Brooklyn. He says he's on Kings Highway and Bedford Avenue and he's afraid to ask the locals for help because it's a bad neighborhood. Kings Highway and Bedford is a nice, residential area, 0,6 mile from the Kings Highway Q train station. No shops or stores on this corner and little chance of anyone who would mug a blind man.
When the orderly comes in and asks Becker if he wants a sponge bath the shadow of the boom mic is visible on the wall next to the door.