When Tex gets hit in the face with a pie the second time, the batter is only over the lower half of his face. When he walks into the sheriff's office to resign, it covers his entire face.
When Ann Miller stands on stage to begin her first big number in the long shot she has her left hand raised to her face. When they immediately cut to the close up she has switched hands.
When they are singing "Ida Red" they cut to a picker with an acoustic guitar on his lap but it sounds like a pedal/lap steel guitar.