hey guys , a qtn to ask.. what ISO should I use for wedding banquet at nite , with sb800 ON . and Aperture mode ? with 18-55mm kit lens\r\n\r\nI would recommend ISO 400-800. Lower ISO means your background will be dark. Apperture as what Isisaxon mentioned. Too wide will render your group photo (with 2-3 rows) blur ar certain distance.