When shooting portraits with 11x14 cameras how powerfull will the flashes have to be?
Will there be enough power in those portable flash systems where the flash and power pack is in the same unit.
Would it be ok too use this with softboxes or is more power needed? The application will be mostly portraits in enviromental portraits mixed with other lamps that are on location.
In your country you might want to contact Profoto for technical information, or maybe even drop by (they are in Skarpnäck at Flygfältsgatan 4)
Telephone 08-447 53 00 and ask for Ronnie Lind. He is a technical representative, not a salesman. The information you get will be useful for any brand (but Profoto makes nice equipment, if you can afford it!)
With largish reflector on my Bronocolor Multicom 80 (600 Ws) I get f/32 at one meter. A silver umbrella will be about the same or maybe half to one stop less. A softbos with two diffusing cloths will be f/22 or f/16. These are approximate f-stops for my approximate distances.
600 Ws seems too little for 8x10 or bigger. Two strobes could be combined maybe?
I just get by with 750 W/S per head, with a two flash kit for maximum output when shooting 8x10 portrait work. But even then, I've got very limited depth of field with a 14" Commercial Ektar. I think I'm getting somewhere in the region of F22 on full power with my main light in a 36x48" softbox, with my subject 4 feet (1.3m) from the light.