Unbalanced colour temperature between artificial and daylight sources — creates blue or orange cast depending on white balance. Often used intentionally for dramatic effect.
You're facing a scene where artificial light and daylight meet — and you deliberately leave them unbalanced. No correction filters, no white balance trick. The result: a visual tension that immediately takes effect. This is the Cold War in lighting — a contrast between warm and cool light sources that disrupts the image composition, and that's exactly what it's supposed to do.
The practical application begins with white balance. If you set the camera for artificial light (approx. 3200K), the incoming daylight (5500K+) becomes an intense blue. If you choose daylight white balance, your lights will turn orange-yellow. Both variations are unpleasant for classic cinema — and that's precisely why the method works. The tension lies in the disharmony. You often see this in thriller scenes: a character sits under cool LED light, while warm daylight streams through a window behind them. No balance. The audience feels the unease without consciously processing it.
On set, you need discipline. Classically, you use correction filters or gels (Straw, Full, Half CTB for artificial light, CTO for daylight) to create harmony — here, you deliberately forgo them. Instead, you clearly document the white balance: either artificial light or daylight, and the other light source type runs into extremes. In the edit or with the DIT, you can refine this further — apply subtle color correction to only one area — but the raw data should clearly show the conflict.
Important: This doesn't work in every scene. In dialogue scenes or emotional moments, this effect can be distracting. But in scenes of tension, isolation, or psychological dissonance — such as a person in an unfamiliar room, or two characters growing apart — the Cold War becomes an invisible weapon. Some DPs also work with this principle in post-production color grading to subtly enhance or intensify it. The point is: you use physical reality (an impossible white balance situation) as an emotional tool. Not as a mistake, but as design.