Visible crew/equipment: Lighting screens are reflected in Hepburn's glasses while she's in the car heading to the set.
Visible crew/equipment: When Hughes is flying the new and faster airplane, you can see the filming crew reflected in the side of the plane. You can see it at full speed but you can see it better if you slow playback down a bit.
Answer: The first sections of the film are shot in two-strip and three-strip technicolor, a common practice in the early versions of color filmmaking that were happening at the time. The scene on the golf course between Howard and Kate Hepburn is a prime example. As far as the later sections of the film, never underestimate the power of digital effects. :)