Canon EOS DIGITAL REBEL XTI instruction manual Histogram, Brightness Display, RGB Display

Sample Histograms

Dark image

Normal image

Bright image

Shooting Information Display

Histogram

The brightness histogram display shows the exposure level distribution, overall brightness and gradation. And the RGB histogram display is suited for checking the color saturation and gradation. The display can be switched with the [xHistogram] menu.

Being able to analyze the histogram and using it to improve the next shot requires advanced knowledge and experience. Only a basic explanation is provided here.

[Brightness] Display

This histogram is a graph showing the distribution of the image’s brightness level. The horizontal axis indicates the brightness level (darker on the left and brighter on the right),

while the vertical axis indicates how many pixels exist for each brightness level. The more pixels there are toward the left, the darker the image. And the more pixels there are toward the right, the brighter the image.

If there are too many pixels on the left, the shadow detail will be lost. And if there are too many pixels on the right, the highlight detail will be lost. The tones in-between will be reproduced.

By checking the image’s brightness histogram, you can see the exposure level bias and the overall tone reproduction condition.

[RGB] Display

This histogram is a graph showing the distribution of the image’s brightness level of each primary color (RGB or red, blue, and green). The horizontal axis indicates the color’s brightness level (darker on the left and brighter on the right), while the vertical axis indicates how many pixels exist for 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 respective color information will be lacking. And if there are too many pixels on the right, the color will be too saturated with no detail.

By checking the image’s RGB histogram, you can see the color’s saturation and gradation condition and white balance bias.

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