I'm just about to start photographing interiors with flash and large format. I expect to use my 4x5 most often, but do intend to try some 8x10 as well. I'm begining to experiment with my lights to see what kind of aperture I could expect when I'm on location. With my 2400 w/s speedotron system I can get f22. This is not quite enough for sufficent depth of field on 8x10. Can I increase the effective exposure by using multiple bursts of the flash, thereby allowing smaller apertures? The interior spaces I'm shooting have no windows so it would not be a problem to turn off the lights and keep the shutter open. If yes, how? Thanks for your advice.