I set up my home studio for some lighting exercises using Alien Bees B800 studio lights and Canon 600EX speed lights. This first exercise was to produce low key and high key lighting with the mannequin head in the same position.
In this low key set up I used one B800 flash unit at its minimum power setting with a 2’x3′ soft box about 1 foot in front of the model. No other lights. Backdrop was a black cloth. Lens is the Canon 135mm, F/2
I then switched the soft box to a 1 foot square (small) photoflex unit. I can see a sharper transition from light to shade with the smaller box. “The bigger the light source the softer the shadows”.
For the high key set up I switched the background to a white cloth and directed a B800 flash unit at it without a diffuser from below and behind the model to ensure a pure white background. The main lite is a B800 flash with the 2’x3′ soft box placed 1 foot in front of model. I further added a 600EX speed lite with a shoot through umbrella on it at the back of the head to keep it from having dark shadows.