I have created this mood board of horror movie posters to get an idea of the main colour scheme used in horror films.
From this mood board I found the colours used are either reds and oranges (hot colours) or blues, whites and soft grey/greens (cold colours). However the main colours are blacks and reds.
The darkness from a young age is always seen as a scary concept, this is why the blacks are used, and the reds are either representing blood or fire, both scary concepts.
The colour schemes used are supposed to set the scene for the whole film. Colours and the brightness of a film can completely change the mood, e.g. if you were watching a girl getting chased by a man with an axe in the day this although scary would have a far lesser impact than if it was in the dark. This may be because of the fear of the unknown, not being able to see every detail of a situation causes the audience to be more on edge as they can't be sure of whats likely to happen.