Vertigo: colors

Madeleine's first appearance, the conclusion of a shot that begins with Scottie looking toward her.
As Madeleine presents herself to Scottie's
gaze, the red decor glows in intensity.
Judy's green dress, which she is wearing when Scottie spots her on a San Francisco street.
Achromatic (colorless) colors: Madeleine's white coat and gray suit; Judy in the black dress (minus the green stole). Kim Novak resisted wearing gray, thought to be unflattering for a blonde, but Hitchcock insisted.
Scottie's red door, Madeleine's green car
A swap of colors in the pivotal apartment scene
The Empire Hotel in San Francisco,
chosen because of its green neon sign.
Scottie's point of view: Judy as Madeleine
Seen in a mirror: green light on the door from which Judy will emerge as Madeleine
Scottie waits
End of the transformation scene
The changing traffic signal in Union Square as Scottie walks through after leaving Midge's apartment for the last time.

Midge's yellow outfit & yellow apartment