foot candle : f/stop ratio at 100asa produces f2.8, right?

[Rob Katz]

foot candle : f/stop ratio at 100asa produces f2.8, right?

i once read about the foot candle to f stop ratio:

You can extrapolate the ASA and footcandle ratio by knowing that at a normal shutter speed of 1/48th of a second,
film rated at 100 ASA
at 100 FC
yields an exposure of F2.8;
200 FC would be F4,
or at 400 ASA at the same illumination the stop would be F5.6.

my fs100 is "rated" at 500 asa (as determined by abel cinema in their picture profile thread)

does that suggest that at 5x the 100 asa described above would allow me to shoot at 1/5th the 100 foot candles needed to produce an exposure of f2.8.

so, will 20 foot candles falling upon a subject with the fs100 set a zero gain (asa 500) shooting a 1/48th, allow me a proper exposure at f2.8?

thanks in advance for any and all thoughts.

be well.

rob
smalltalk productions/nyc