P3-D65 Trim

Mastering for the Home Theater

A feature film’s primary color grade is almost always performed in a theatrical environment, targeting the specifications of a digital cinema projector. The global standard for this is the DCI-P3 color space, which uses a specific ‘white point’ that gives white a subtle greenish tint, optimized for the dark environment of a movie theater. However, when that film is prepared for home release on platforms like Netflix, Apple TV+, or 4K UHD Blu-ray, it must be adapted to a different, albeit very similar, standard: P3-D65.

Let’s break down the term:

• P3: This refers to the DCI-P3 color gamut, which is the range of colors that can be displayed. Both digital cinema and modern HDR televisions use this same wide color gamut, which is much larger than the older Rec. 709 standard used for traditional broadcast and DVDs.
• D65: This refers to the color of white, known as the ‘white point.’ D65 (short for Daylight 6500K) is the industry standard white point for virtually all consumer displays, from televisions and computer monitors to smartphones. It is a pure, neutral white, carefully calibrated to represent daylight.

The ‘Trim Pass’ Explained

The process of creating the home entertainment master is called a ‘trim pass.’ After the theatrical grade is finalized, the colorist will view the film on a professional reference monitor that is precisely calibrated to the P3-D65 standard. Because the P3 color gamut is the same, the overall colors will be very close. However, the shift from the theatrical greenish-white to the neutral D65 white will cause a subtle change in the feel of the entire image. The colorist then performs a ‘trim,’ making small, nuanced adjustments to the brightness, contrast, and color balance to ensure that the creative intent of the original grade is perfectly preserved under the new D6G5 white point. This is a critical quality control step that ensures the version of the film you watch at home is a faithful and accurate representation of the filmmaker’s vision.