Canon EOS-1DX Instruction Manual page 213

Exposure simulation
Exposure simulation displays and simulates how the brightness of the
actual image (exposure) will look.
• Enable (g)
The displayed image brightness will be close to the actual
brightness (exposure) of the resulting image. If you set exposure
compensation, the image brightness will change accordingly.
• During e
Normally, the image is displayed at the standard brightness to
make the Live View image easy to see. The image will be
displayed close to the actual brightness (exposure) of the resulting
image only while you hold down the depth-of-field preview button.
• Disable (E)
The image is displayed at the standard brightness to make the Live
View image easy to see. Even if you set exposure compensation,
the Live View image is displayed at the standard brightness.
If you set an expanded ISO speed setting as [Maximum] in [ISO speed
range], Live View shooting will be possible under darker conditions.
Even if a low ISO speed is set, noise may be noticeable in the displayed
Live View image under low light. However, when you shoot, the image
recorded will have minimal noise. (The image quality of the Live View
image is different from that of the recorded image.)
3 Menu Function Settings
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