Canon EOS REBEL T6i Instruction Manual page 133

If the exposure obtained in step 1 differs greatly from the standard

exposure, a correct white balance may not be obtained.
In step 3, the following images cannot be selected: Images captured

while the Picture Style was set to [Monochrome] (p.126), images
processed with a Creative filter, cropped images, and images taken with
another camera.
Instead of a white object, a gray chart or 18% gray reflector

(commercially available) can produce a more accurate white balance.
The personal white balance registered with EOS Utility (EOS software,

p.404) will be registered under [O]. If you perform step 3, the data for
the registered personal white balance will be erased.
Select [Custom White Balance].
2
Under the [z2] tab, select [Custom

White Balance], then press <0>.

The custom white balance selection
screen will appear.
Import the white balance data.
3
Select the image that was captured in

step 1, then press <0>.
 On the dialog screen that appears,
select [OK] and the data will be
imported.
When the menu reappears, press the

<M> button to exit the menu.
Select [O (Custom)].
4
Press the <WB> button.

Select [O (Custom)], then press

<0>.
B: Matching the Light SourceK
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