Good day, I have been using 2 Alienbee B800 (320WS) flashes for a few years now with my DSLR, but I want to start doing portraits with my 4X5 camera. I plan to use Kodak Portra 400 film and I was wondering (roughly) if my flashes are powerful enough (18% grey looks 18% grey)? My typical shot is 1-2 persons, with 1 flash going through a softbox just outside the frame of the photo (no more than 6ft away), with the second strobe used for separation/background lighting either with a reflector or through an umbrella - I may use window light as well, if it is strong enough. I am guessing for portraits on 4x5, F16-F22 would be where I want to be (not a big fan of super shallow depth of field). I may invest in another flash soon, however, I like the B800 for their compactness, as I do plan to throw everything in a Kelty Redwing 50 (tried it, works great) so that I can move around (I typically take pictures at a friends home or some other interior space).