RGB plays a foundational role on digital screens. This article introduces what RGB means, how it works, and its practical applications.
📖 Table of Contents
RGB: The Additive Primaries of Light
RGB is the abbreviation of red, green, and blue, and it is widely used in electronic display devices such as computer screens and phone screens.
Additive Mixing
The essence of RGB is additive mixing. RGB adds light of the three wavelengths red, green, and blue at different intensities to produce different colors. It has the following characteristics:
- BlackWhen the intensity of all three lights is 0, the result is pure black.
- WhiteWhen the intensity of all three lights reaches its maximum, the result is pure white.
- IntermediateAdjusting the intensity of any one or more of the lights produces different intermediate colors.
The RGB system reproduces color by simulating the way the human eye perceives light.
The Quantified Expression of Color
To let computers control RGB color, the intensity of each color is quantified into specific values. By bit depth, RGB can be divided into 8-bit RGB and 10-bit / 12-bit RGB:
Each color has an intensity range of 0–255. Combining the three colors can produce about 16.77 million colors, which is more than enough for everyday needs.
Each color has an intensity range of 0–1023 or 0–4095, and can produce about 1 billion colors.
RGB generally comes in three formats:
- Numeric format
(255, 0, 0)Represents pure red. - Percentage format
(100%, 0%, 0%)Also represents red. The percentage is calculated as 255/255=100% and 0/255=0%. - Hexadecimal format
#FF0000This value is obtained by converting (255, 0, 0) to hexadecimal.
Where RGB Is Used
The most basic use of RGB is on screens. In a computer’s display settings or monitor preferences, you can adjust the intensity of the three RGB colors to correct the screen color. If you need high color accuracy, you can also adjust RGB in the graphics card’s control panel.
RGB is mainly used in creative fields such as design and photography. For example, image editors like Photoshop use RGB for color grading, web development uses RGB in CSS to set colors, and film and television production uses RGB to correct picture color and set the mood.
RGB adjustment in system display settings, monitor preferences, and graphics card control panels corrects the screen color.
RGB color grading in image editors such as Photoshop.
Using RGB in CSS to set colors.
RGB is used to correct picture color and create atmosphere.
Things to Keep in Mind When Using RGB
RGB is suited to screen display. If a design needs to be printed, you should convert it from RGB mode to CMYK mode in advance. You can use this site’s Color Unit Converter.
Different scenarios use different RGB color spaces—for example, the web uses sRGB, while photography uses Adobe RGB. If you do not pay attention to this, colors may shift when displayed across platforms.