Foot candles

Gary Cote gcote at
Fri Oct 12 10:25:42 EST 2001

At 03:39 PM 10/12/01 +0100, Magaly wrote:
>Dear Plant-Eders
>I am in crunch here for time.  I know this question has come up in the list
>some time ago.  What is the conversion factor from foot candle to moles
>photons/sq. meter/sec?
>Not a shred of evidence exists in favor of this idea that life is serious
>                                                           --Brendan Gill.
>Magaly Rincón-Zachary, Ph.D.
>Associate Professor and Graduate Coordinator
>Biology Program
>Midwestern State University
>3410 Taft Blvd.
>Wichita Falls, TX 76308
>Phone:	(940) 397-4254
>Fax:	(940) 397-4831
>E-mail:	magaly.rincon at

The simple answer is you can't convert foot-candles to mol/m2 s.

1 fc = 1 lumen /ft2
1 lux (the SI unit) = 1 lumen / m2

so 1 fc = 10.76 lux

A lumen is a measure of energy and so the conversion of lumens to moles
depends on the wavelength.

Time doesn't enter the equation anywhere.

This information is from the lab manual I wrote for in-house Cell Biology.
I'm not an expert on light measurements.  If I'm wrong, I hope to be

Dr. Gary Coté
Assistant Professor
Department of Biology
Box 6931
Radford University
Radford, VA 24142-6931

Ph: 540-831-5630
Fax: 540-831-5129
email: gcote at


More information about the Plant-ed mailing list