Canon MARK IV User Manual (en)

 Setting the Flash
Select [Flash C.Fn settings].
Turn the <5> dial to select [Flash C.Fn settings], then press <0>.
Set the flash function.
Turn the <5> dial to select the function number, then set the function. The 
procedure is the same as setting the camera’s Custom Functions (p.204).
In step 1, select [Clear all Speedlite C.Fn’s] to clear all the Speedlite’s 
Custom Function settings (except [C.Fn -0: Distance indicator display]).
Flash C.Fn Settings
Canceling Speedlite Custom Function Settings
If you use an EX-series Speedlite and the Speedlite Custom Function’s [Flash 
metering mode
] is set to [TTL], the flash will always be fired at full output.
Metered Manual Flash Exposure
This is for close-up flash photography when you want to set the flash level 
manually. Use an 18% gray card and an EX-series Speedlite which has 
manual flash mode. Follow the instructions below:
1. Set the camera and Speedlite settings.
• Set the camera’s shooting mode to <a> or <f>.
• Set the Speedlite to manual flash mode.
2. Focus the subject.
• Focus manually.
3. Set up the 18% gray card.
• Place the gray card at the subject’s position.
• In the viewfinder, the entire spot metering circle at the center should 
cover the gray card.
4. Press the <I> button. (8)
5. Set the flash exposure level.
• Adjust the Speedlite’s manual flash level and the camera aperture so 
that the flash exposure level aligns with the standard exposure index.
6. Take the picture.
• Remove the gray card and take the picture.