The books on this subject (how many shots to take) generally say that you will, on most occasions, do fine with 3 shots (+2/-2,0 eV). You need to look at the histogram, to make sure there is adequate exposure in the deep shadows.


For subjects that move around a lot, it can be a challenge to bracket 5 or 7, because now you're fiddling around with the exposure compensation dial, and that takes up more time. Since you're trying to minimize movement in the scene, that extra time means that the subject has moved, which then translates into "ghosting" on the subject. Despite the various fixes in these programs for removing ghosting, it is tough to correct.


To see if there is a benefit, find a truly stationary scene, and take the 3 shots with 2 eV width, then try another with 5 and another with 7.


Like I said, it's the histogram that tells you whether you've exposed the scene properly, and if 3 bracketed shots does it for you, I doubt you will see a difference with 5 or 7 at 1 eV.