WTB, flash kings (manual mode on the 550EX)

[timmyquest]

Last night was the first time i dabbled i seriously dabled into manual mode on the 550EX. It allowed me to get, for the most part, identical exposiers on each one of my photos. Something i'm not use to on my 300D. It's not so much that they are ever "off" it's just that they arnt the same.

So, happy with the results i'd like to use it more often but what i cant seem to figure out based on the manual is what exactly this all means.

What exactly does 1/1 mean

what does 1/128 mean.

What rules does one use to figuring out whats best other then *click* check LCD...and buying a light meter of course.

[Jon]

1/1 means full power, GN=55 (meters). 1/128 means 1/128 power (about 8 stops less exposure). As for figuring what setting to use, aperture * distance = GN. If you want a larger aperture than you'd get at full power, drop down one setting for each stop. You can also use the power ratios to control light balance in multi-light settings. Main is set at 1:1, slave is at 1:4, and there's your lighting ratio (after you figure what f/stop to use).