User:Difference engine/Day for night



Day for night, also known as nuit américaine ("American night"), is a cinematic technique used to simulate a night scene while filming in daylight. It is often used when there is too difficult or expensive to actually shoot during nighttime. Because both analog film stocks and digital image sensors lack the sensitivity of the human eye in low light conditions, night scenes recorded in natural moonlight may be underexposed to the point of being nearly entirely black. Using day for night avoids this issue by using daylight to substitute for moonlight. As film stocks have improved in sensitivity, shooting day for night has become less common in recent years.

Technique
Some techniques use tungsten-balanced rather than daylight-balanced film stock or special blue filters; under-exposing the shot (usually in post-production) can create the illusion of darkness or moonlight.

Historically, infrared movie film was used to achieve an equivalent look with black-and-white film.

With digital post-production techniques it is also common to add or intensify glare and light shattering from light sources that would otherwise be less pronounced in daylight, such as windows of indoor lighting, outdoor artificial lights, headlights on cars and more.

The title of François Truffaut's film, Day for Night, (1973) is a reference to this technique.