3Auto Correction of Brightness and ContrastN 
If the image comes out dark or the contrast is low, the brightness and contrast can be corrected automatically. This function is called Auto Lighting Optimizer. The default setting is [Standard]. With JPEG images, the correction is done when the image is captured. For RAW images, it can be corrected with Digital Photo Professional (provided software, p.340).
In Basic Zone modes, [Standard] is set.
1
2
3
Select [Auto Lighting Optimizer].
Under the [A3] tab, select [Auto Lighting Optimizer], then press <Q/ 0>.
Select the setting.
Select the desired setting, then press <Q/0>.
Take the picture.
The image will be recorded with the brightness and contrast corrected if necessary.
Under [54: Custom Functions (C.Fn)], if [3: Highlight tone priority] is
set to [1: Enable], the Auto Lighting Optimizer will be set automatically to [Disable] and the setting cannot be changed.
Depending on the shooting conditions, noise may increase. If a setting other than [Disable] is set and you use exposure compensation or flash exposure compensation to darken the exposure, the image may still come out bright. If you want a darker exposure, set this function to [Disable].
In step 2, if you press the <B> button and uncheck <X> the [Disable during man expo] setting, the Auto Lighting Optimizer can be set in the <a> mode.
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