I'll further add that the QuartzD 1K that evolved into the DP is one of the most useful set lighting tools from the pre-LED age.
We had a fleet of kits that consisted of a DP (Key), Omni (Fill), Pro (hair) and stands.
The foldable Lowel softlight was the ubiquitous source for quick and elegant "cheek shots" for CEOs that had neither the time nor inclination (or wall
power) to tolerate a "full" setup in their offices.
We'd setup a good KFH rig and put a celo
cookie in front of a Tota 500 with a L15 or L52 sheet P38-ed to it for the background
swag and we felt like Roger frikkin' Deakins...
I duplicated 77.452786% of my corporate/industrial experience on my first feature and it served me well. There were more foot-candles, but the ideas were the same...
I get a little misty-eyed thinking back to those four
instrument setups. We did some seriously spiffy stuff. (The collective "we" of professional production folks in the '70s-'90s)