The advent of digital post-production has made this process more about art and less about science. Film negatives could be exposed to different chemicals for different amounts of time to bring out the reds, greens, or blues in the image (this is why color correction is sometimes referred to as “color timing.”) Additionally, various bleaches, washes, and other photochemical processes could be used to affect the final image. Until relatively recently in the history of cinema, color grading was a purely chemical process. Many criticized the film for being overly grim – could something as simple as increasing the saturation have changed the film’s overall feel? It’s certainly possible. After the massive success of Christopher Nolan’s darkly-themed and darkly-graded Dark Knight trilogy, director Zack Snyder adopted a similar look for his Superman reboot Man of Steel.
Sometimes, color grading and stylization in a film can be over-used. Even on films where the color grading doesn’t draw attention to itself, the look of the film is always a conscious choice. Some feature films have incredibly stylized color grades – think about how different O Brother, Where Art Thou?, The Matrix, 300, Traffic, or Moonrise Kingdom would be without their distinctive color palettes. Just like altering music can take a scene from sentimental to scary to silly, color grading can completely alter the feel of the footage you’re working with.
Few things transform a project like color grading.