Visible crew/equipment: When McMurphy tries to make the "dancer" vote for the world series he dances with him through the hall. When he does that you see the shadows of the boom mike and cables on them. (00:43:50)

Visible crew/equipment: In the second basketball scene, when McMurphy shouts at Martini because he threw the ball against the fence, there's a lot of equipment visible on the left side, most prominently a big spotlight. (01:05:20)
Answer: It's better explained in the novel, where the Chief is the narrator. Essentially, he played deaf and dumb, so he'd be left alone by the Nurse and the staff; seeing what they did to the other patients, he figured the less he was noticed, the better. In this way, he is privy to a lot of the seedier goings-on, since they don't think he can hear what they're saying or tell anyone what he's seen.