CamCyclopedia
Contents
- What is the color gamut of display and camera?
- Color gamut of the S23 camera
What is the color gamut of display and camera?
Before explaining the color gamut of a camera, it's important to understand the color gamut of a display. The color gamut of a display is the maximum range of colors that can be represented on the display.
The specs for our ViewFinity S8 (Monitor) describe it as follows. [1]
Display represents each of the three primary colors, Red, Green, and Blue, on CIE x, y coordinates (which represent colors in physical coordinates), and the area between the three points is the color gamut. In the image above, 100% sRGB and 98% DCI-P3 means that it covers the entire sRGB color gamut and 98% of the DCI-P3 color gamut. sRGB, DCI-P3, etc. are standards that define color gamuts, and there are standards that are even wider. A wider gamut allows for a wider range of colors to be represented and more real-life-like colors.
The color gamut of a camera is slightly different from the color gamut of a display. The color gamut of the camera is determined by which display color space it is tuned for, meaning that the same camera H/W can be tuned for both sRGB and DCI-P3. If the color gamut of the camera and the display are the same, it will display colors to the maximum color space of the display. However, if the camera and display have different color gamuts, it will display the smaller color space out of the two. This operation is color management system (CMS). If the CMS isn't working properly, you might see colors darker or lighter than they actually are.
So how does an image viewer know if the camera's color gamut is sRGB, DCI-P3, or something else? The color gamut information is recorded in the Exif area as an ICC Profile. The ICC Profile is a standard created by an organization called the International Color Consortium to ensure that cameras and displays use the same color gamut. [2]
The ICC Profile contains a profile description, color gamut information (XYZ values for red, green, and blue colors), and tone reproduction information.
Color gamut of S23 camera
Cameras prior to the Galaxy S23 used the sRGB color gamut for reasons such as CMS support in image viewers and third party app compatibility. However, now we have resolved compatibility issues by collaborating with third party app companies and supporting DCI-P3 from S23 to experience a wider color gamut. Although the color gamut of DCI-P3 can express a wider range of colors than sRGB, the white point (XYZ coordinates of white) is still different from common displays (mobile, monitor, TV, etc.). So, to make it universally relevant, we have modified the white point of DCI-P3 to D65 (6500K color temperature) and the tone reproduction characteristics to 2.2 gamma.
The OLED displays used in Samsung cameras have a wider color gamut and richer colors than the DCI-P3, when used in vivid mode, but the color accuracy is not as good as in Natural mode. In Natural mode, the color reproduction is identical to the DCI-P3's color gamut.
※ DCI-P3 color space: Developed by Digital Cinema Initiatives organization, USA to be used as the color gamut in digital projectors. It represent a 25% wider color space than sRGB. [3]
P3 / sRGB Image Difference
The image below shows the difference between a P3 image and an sRGB image. When viewed on a P3 display, the P3 image appears deeper in color compared to the sRGB, and when viewed on an sRGB display, the two images look identical (assuming the browser supports the CMS operation on a normal basis).
Color display difference according to image/display color gamut (CMS works)
The image above shows how colors are represented based on the color gamut of the image and display.
On a P3 display, a P3 image can express a wider range of colors than a sRGB image. Therefore, if you want to take the image of a dark primary colored object and view it on a P3 display, the P3 image is a better choice. It can express colors closer to the original than the sRGB image. (Case ①) However, a sRGB image will have a narrower color range than a P3 image because it cannot show colors beyond the sRGB color range from the time the image is saved. (Case ③)
When viewing a P3 image on a sRGB display, colors beyond the sRGB color gamut are not expressed and are saturated to the maximum sRGB color gamut. (Case ②)
As explained above, if the color gamut of the camera and the display differ, the CMS function must work properly to express normal colors. CMS is a function that changes the RGB values so that the same physical color can be expressed on the display even if the color gamut is different. (For example, in the above image, the RGB values of ② and ③ are changed to 234↔255 and 225↔246.) This function is usually provided by an image viewer and does not change the image itself. Adobe Photoshop includes a function that changes the color gamut to change/save the image itself. This feature includes converting the color gamut and storing the image's color gamut information (ICC Profile) in the image Exif information.
Color display difference according to image/display color gamut (CMS does not work)
The preceding description assumes that your CMS is working properly. However, if you're seeing in a viewer that doesn't support your CMS, or if you're viewing an image that does support your CMS but doesn't have color gamut information, you won't see the colors as intended. You'll see deepening or fading of colors.
When viewing a narrow gamut image on a wide gamut display, the colors will be darker (Case ①).
When viewing a wide gamut image on a narrow gamut display, the colors will be pale/weak. (Case ②)
■ Related Content
Color in Camera - Samsung Members
What is Color Science? - Samsung Members
CamCyclopedia Index - Samsung Members
You can also check out CamCyclopedia at any time by going to Community -> Category (app) -> CamCyclopedia -> "CamCyclopedia Index".
References
[1] https://www.samsung.com/sec/monitors/high-resolution-ls32b800pxkxkr-d2c2/LS32B800PXKXKR/
[2] https://www.color.org/index.xalter
[3] https://www.dcimovies.com/
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