OK, so I'm going to jamaica for a wedding (fiance's brother) and vacation. They've asked me to shoot portraits/groups of up to 10 ppl because they basically only get an hour (ceremony and cutting/toast included so a half hour for pics with their parents, etc) with the professional photographer. I obviously also plan on taking pics of anything and everything while I'm down there.. first time off the continental US/canada (yay)! I need a couple recommendations from some who are more experienced with this pic style, I definitely am not.
I've got:
20D
18-55 IS
55-250 IS (borrowed, because its better than my sigma 70-300)
50 1.8 Mk1
I'm lookin at splitting a lens rental with the bride/groom for the trip and I'm torn between choices.
10-22
17-35
17-55
24-70
(other recommendations open, but these lengths seemed to make sense and are all fast lenses)
or would an experienced portrait photographer recommend a really good crop prime length? Would my 50mm 1.8 be very nearly as good?
second question, should I use some kind of off camera flash for fill? I'm assuming I'll be able to set up portraits in a well lit location, but depending on what they want for a backdrop who knows if the lighting direction will be optimum. This I would plan on buying so keep recommendations budget friendly please.
General setup recommendations for setup recommendations in shooting (mode, fstop, etc) would be appreciated as well. I'll be honest, I'm a little nervous.