What is Rec. 709?
Question: What is Rec. 709?
Answer: Rec. 709 is a common term to describe the color space used in HD video mastering. Even though this is associated with HD resolution, it is still the most common color space for delivering higher resolutions like UHD 4K for home video content.
What is Rec. 2020?
Question: What is Rec. 2020?
Answer: Rec. 2020 refers to a wider color space that was standardized for UHD 4K video mastering. Because most displays are still only capable of smaller gamuts than Rec. 2020, it is being used as a 'container' for smaller gamuts like P3 (see article "What is P3?").
What is P3?
Question: What is P3?
Answer: P3 is a theatrical color space standardized by DCI, used in color grading. DCI-P3 gets converted into the XYZ 'container' for DCP packaging and projection in theaters. P3 is also often used in HDR grading.
What is Gamma?
Question: What is Gamma?
Answer: Gamma refers to the relationship between video signal and light output. A gamma of 1.0 (linear) would mean that an increase of 2x in signal would have a 2x increase in light output. However, most displays have a gamma of between 2.0 and 2.4.
For video mastering, gamma 2.4 was standardized in ITU-R BT.1886.
For theatrical mastering, gamma 2.6 was standardized by DCI. For HDR, a new 'gamma' was introduced called PQ and standardized as SMPTE ST.2084 (see FAQ "What is PQ?").
What is PQ?
Question: What is PQ?
Answer: PQ stands for 'Perceptual Quantizer' which refers to a new 'gamma' or transfer function for HDR. It uses the human eye as the perceptual basis for its signal-to-light relationship. For this reason, it is highly efficient from very low to very high light levels and is used for encoding HDR images.
What is a LUT?
Question: What is a LUT?
Answer: LUT stands for 'Look Up Table' and it is a table of numbers which map from Input to Output values. LUTs have many uses, but are most commonly used for converting images from one color space to another.
What is ACES?
Question: What is ACES?