Canon MARK IV User Manual (en)

In step 4 on page 194, select the printing 
effect. When the <e> icon is displayed 
next to <z>, press the <B> 
button. You can then adjust the printing 
effect. What can be adjusted or what is 
displayed will depend on the selection 
made in step 4.
The image brightness can be adjusted.
Adjust levels
When you select [Manual], you can change 
the histogram’s distribution and adjust the 
image’s brightness and contrast.
With the Adjust levels screen displayed, press 
the <B> button to change the position of 
the <h>. Turn the <5> dial to freely adjust 
the shadow level (0 - 127) or highlight level (128 - 255).
Effective in backlit conditions which can make the subject’s face look 
dark. When [On] is set, the face will be brightened for printing.
Red-eye corr.
Effective in flash images where the subject has red eye. When [On
is set, the red eye will be corrected for printing.
 Adjustment of Printing Effects
The [kBrightener] and [Red-eye corr.] effects will not show on the screen.
When [Detail set.] is selected, you can adjust the [Contrast], 
[Saturation], [Color tone], and [Color balance]. To adjust the [Color 
], use <9>. B is for blue, A is amber, M is magenta, and G is 
green. The color in the respective direction will be corrected.
If you select [Clear all], all the printing effect settings will be reverted to 
the default.