Canon EOS R5 C VR Creator Kit with RF 5.2mm f/2.8 Dual Fisheye Lens - Manual (Page 456)

[RGB] display
This histogram is a graph showing the distribution of each primary color's brightness
level in the image (RGB or red, green, and blue), with the horizontal axis indicating the
color's brightness level (darker on the left and brighter on the right) and the vertical axis
indicating the pixel count at each color brightness level. The more pixels there are
toward the left, the darker and less prominent the color, and the more pixels there are
toward the right, the brighter and denser the color. If there are too many pixels on the
left, the corresponding color information will be lacking, and if there are too many pixels
on the right, the color will be too saturated, without gradation. By checking the image's
RGB histogram, you can see the color's saturation and gradation conditions, as well as
the white balance bias.
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