How do I get the 600 ex-rt off of ratios and put in power output?

[BDAgirl]

I can't find it anywhere in my manual or the custom functions. For instance, it is showing the ratio of 1:4 instead of the power  output of 1/4 power.

I am using a Mark III.

Thank you!

[Skirball]

You have to put it in manual mode, instead of eTTL.