Setting the Canon 5D MkII for Bracketed exposures : What C1, C2, C3 are really about
Say you come across a scene you wish to photograph that has a large dynamic range, it may be useful to set the Custom settings on the 5D MkII to take bracketed exposures:
1. To be sure you have everything in dynamic range spot meter your Brightest and darkest Points. That will give you an idea of dynamic range in question and will help decide if the 3 exposure range is enough. (Often it's not the case)
2. You will have to decide the EV range stop between bracketed exposures 1/3rd of a stop,2/3rds,1 stop etc
3. With C1,C2,C3 configured for bracketing, you can have 9 shots across the exposure range at your fingertips.
4. Setting the drive mode to Multi frame has you pressing the shutter button only once so that the camera takes 3 shots at a go. Setting the mirror up to avoid mirror slap and using the timer and a tripod shoud get you the sharpest pictures.
I shoot just RAW instead of RAW+L. That has me dealing with less files clogging up the memory card.
There are more scenarios and elaborate descriptions at the Canon link below.