[Benji]

The fill light should not cast any shadow. It should create very flat lighting. The main is what casts a shadow thereby creating form and dimension in the image.

"Target range" for shooting in my camera room. When I bought most of my studio lights 20 odd years ago, they were (of course) made for film. My medium format camera lenses that I had at the time had a lot less DOF than does my new digital camera lenses at the identical aperture. So I actually have too much power for my digital lenses. Digital lenses have tons of DOF even at relatively wide apertures like f/2.8-f/4.0, but since I still have powerful lights, I must shoot at f/10 or thereabouts. I could stack a bunch of ND filters on the lenses to cut the power, or place NG gells across all my softboxes, but I ain't gonna! So since I know at lowest power and at about 8 to ten feet from the subject my fill light will give me f/4.5, I use that as a starting point to set the rest of the lights.

Ben