Wireless Speedlite ratio question

I can't find the answer to these two questions anywhere...

QUESTION 1.
Let's say I have three 580EX's; one master on the camera, one slave in group A, and one slave in group B. I am shooting in fully automatic ETTL-II mode and have set the A:B ratio to say 4:1.

If I have the on-camera master set to NOT fire, then all is good and I understand my light ratios, A=4 and B=1.

BUT, if I have the on-camera master set to fire, what is the ratio of it's contribution of light to the picture? It is contributing something but it is not set by me.

QUESTION 2.
Same situation and question as above but in Manual mode instead of ETTL-II automatic. From the master you set the ratios of each slave but you only set the master to fire or not to fire.

I hope this makes sense. I has been bugging me for some time now.

Thats the EXACT same question I was about to post about my two 550EX combo too. On the master you can set Ratio for slave A to say 1/32 but what about the master itself? All you can set is Fire or NOT fire?

For 3 580EXs, when master set to fire, the master belongs to group A. so...

(Master + Slave on group A) : Slave On group B = 4 : 1

For question 2, there are 2 scenarios: 1) all EXs in manual mode, then the master will do the triggering plus what ever flash output is set on itself( or not fire at all), the ratio is controlled by the photog. 2) Master set to M mode after the ratio is turned on, the slaves can be set in ETTL mode, then each flash's individual output can be set on the master unit, like 1/2 of max power on master A, 1/4 on slave in group B, and 1/8 + 0.3 on slave C-----but anyway, the camera user set ratio manually on M modes

Does this apply to the 550EX too? Pressing the Mode button does nothing on the slave once its set to "Slave".

gjman wrote in post #2833095
Does this apply to the 550EX too?

Yes.

gjman wrote in post #2833095
Pressing the Mode button does nothing on the slave once its set to "Slave".

Press and hold the Mode button to switch the slave to manual mode. The "M" icon on the LCD screen will blink.