thanks. but i have one more query. I read on websites saying that using slow sync mode you can lit up your friend in the foreground as well as brighter background due to slower shutter speed, but the thing is : your frined (subject) will have motion blur cos they will not stay motionless. if you use slower shutter speed, wont you need to tell your friend not too move before the shutter ends? how can you possible ask your subject not to move till you say so?