how big ur group? different location different settings, and i really don't know where TS location is. but shutter at 1/30 not encourage, and iso i agreed, actually 400 is maximum to me for big group photo.
My biggest group is 300 plus minus in school hall, and 200 plus at a hotel.
If really shooting such a big group, I would recommended Mertz:thumbsup: Save all the trouble of carrying the big lights. Learning curve would not be so bad if u are a manual user.
Smurfman, can I chk why not at 1/30?