As Kostas noted, it's sometimes for insurance, but it also gives the knowledgeable photographer a couple of interpretations of the scene with which to work
Further, you must understand that exposure bracketing is only really workable on some scenes for some types of photographs under some circumstances. It's not a panacea. It's a technique. Shel > On Mon, 23 May 2005, Cory Papenfuss wrote: > > Don't take it as a flame, but then what is bracket exposure for if > real photographers know they got it right before they even shoot?

