Canon EOS-1DX Instruction Manual page 332

3 Custom Function Settings
AE Microadjustment
Normally, this adjustment is not required. Perform this
adjustment only if necessary. Note that performing this
adjustment may prevent the correct exposure from being
achieved.
You can fine-tune the standard for exposure metering. This adjustment can
help if automatic exposure always makes the image look too dark or too
bright even without any exposure compensation.
OFF: Disable
ON: Enable
Select [Enable] and press the <Q> button. The adjustment screen will
appear. The adjustment can be made up to ±1 stop in 1/8-stop
increments. If the exposure metering tends to underexpose, set it to the
plus (+) side. If it tends to overexpose, set it to the minus (-) side.
FE Microadjustment
Normally, this adjustment is not required. Perform this
adjustment only if necessary. Note that performing this
adjustment may prevent the correct flash exposure from being
obtained.
You can fine-tune the camera's standard for flash exposure. This
adjustment can help if the automatic flash exposure always makes the
subject look too dark or too bright even without any flash exposure
compensation.
OFF: Disable
ON: Enable
Select [Enable] and press the <Q> button. The adjustment screen will
appear. The adjustment can be made up to ±1 stop in 1/8-stop
increments. If the flash exposure metering tends to underexpose the
main subject, set it to the plus (+) side. If it tends to overexpose the main
subject, set it to the minus (-) side.
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