This might be interesting....
Luchford on how the Hana S shoot was done....
a friend told me to look at this and i find it really interesting,ill try and answer your question,i shot on digtal lightphaze h25,which i love and use all the time,even for large billboards its good, all the lights are film lights all tungsten,didos,1ks 2ks,allot of difussion.and most important dimmer switches on all lights to bring everything into balance,i cant remember exactly as it was a while ago but there is probably about 20 lights making up this shot,the background is made of silk and blown through a wind machine wich i took from a picture of a communist rally in russia on a windy day! the big problem was to bring the background and make it flow with the foreground so the model dosnt look stuck on, her hair isnt blowing! i have a good hair guy that makes it look like that,its actually stiff with hairspray, i used red gels on the lights that spread through the background and onto the model which made the connections and made it feel whole,for images this soft i wou;ld stay away from flash, i think i shot it on a mamiya and about 1/8 sec or poss 1/15 no more,thats about all i can recall, good luck, i hope it works out, glen luchford.