Here's my first question:

I've searched through this site and found there has been extensive discussions on pre-exposure, but I have not been able to find exactly what I need. A means to calculate the Illuminance from a traditional ISO, Shutter Speed, Aperture exposure setting.

Film is documented in the luminous exposure curves as density versus lux seconds.

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If my pre-exposure light source produces a set exposure, how do I convert this into lux to then turn down the exposure to something specific, such as 0.0032 lux in my pre-exposure ?