What are color spaces and what do the terms Rec.709 and Rec.2020 mean?

In the world of cinematography, it is necessary to understand the meanings of the terms color spaces and the meaning of the word Rec.709. You may have come across these terms when you were shooting material in Log or RAW format, or you may have faced a problem in determining the meaning of these terms while coloring a visual material that you are working on. Today, within our article, we will give a comprehensive and simplified explanation of the meanings of color spaces, as it is one of the most complex topics for those who want to begin understanding the world of filmmaking in the correct technical and scientific form. Color space and visual color spectrum? The human eye can see a specific range of rays that make up the colors we know and distinguish. All the colors after red are called infrared rays, and those after violet are called ultraviolet rays, and they are colors that we cannot see. The spectrum of those colors that we can see is measured in nanometers, and those colors fall between 380 nanometers and 740 nanometers. What is the CIE 1931 chart?

In 1931, the International Commission on Illumination (CIE) quantified the human ability to see colours, and created what is known as the Color Coordinate Chart, or CIE 1931. The chart identifies all color values ​​that the human eye can see with x and y coordinates. Notice with me that the numbers written in blue are the same colors as in Picture No. 1. Now, from this point in the article, we cannot translate the scientific terminology used, and adopt those terms as translated in the field of work, so in the upcoming explanations in the rest of the articles, we will limit ourselves to mentioning the foreign term as it is internationally approved.

What is the meaning of Color Gamut and what is the REC.709 space? Color Gamut is a specific color space that falls within the visible color spectrum. In the image below we notice a color coordinate chart, or what is known as CIE 1931, and several triangles are located within that chart, including a triangle that specifies values ​​for a specific color space called REC.709. Hence, we find that the REC.709 color space, or REC.709 Color Gamut, specifies only certain values ​​of the colors that we can see.

So REC.709 Color Gamut can be considered as a communication language between your camera and the display device of the material you are photographing, which in the case of REC.709 are the screens on which we work, browse, watch movies, and mobile phones. The camera shoots material in Log or RAW formats, almost without color, but when those files are converted from Log or RAW formats to the REC.709 color space, those materials become viewable in their true, natural colors. From theory to practical To clarify the topic more about color spaces, I used the Arri color tool, to take samples for comparison. In the examples below, and on the right, we notice the image in its blurry form as it was photographed using the LogC format of ARRI cameras, known as LogC Wide Gamut. Now we have visual material with a color spectrum and a wide area. To convert it to true colors as seen by our eyes, we must convert this material from LogC Wide Gamut to Rec 709, and when Transforming it, we find that the image becomes in its true colors, as it is supposed to be in reality.

What is the area of ​​Rec.2020 Color Gamut? In our talk about the Rec709 color space, we were talking about the colors that can be displayed on the screens that we use on a daily basis, such as phones, computers, etc., but with the development of display technologies, and the emergence of advanced screens in their display of color quality, we have a new space called Rec.2020, which is a wider color space than the previous Rec709, allowing us to display colors in a wider range, and it is a space that is almost very close to the full color space that we can see. No professional display can fully and accurately display the Rec.2020 Color Gamut; monitors that support the Rec.2020 Color Gamut can only display a portion of it (this portion is stated as a percentage of the total color space coverage).

Therefore, the Rec.2020 Color Gamut is supported in UltraHD Blura displays, and it is considered the largest color space used in filmmaking and creative visual content. I hope that this article is sufficiently comprehensive regarding the meanings of the terms Rec709, Rec2020, and color spaces. I would like to remind you that if you find any questions, you can send your inquiries by clicking on  Contact Us, and you can also follow us through our account at 

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