Saturday, March 22, 2008
Lux = 50 x fnumber² / (exposure time in seconds x ISO film speed)
To measure Lux with a camera's light meter, use the equation above. Taken from this page.
Here are conversion factors from Lux to Photosynthetic Photon Flux for varius light sources.
Sunrise or sunset on a clear day - 400 Lux
Sunlight on a cloudy day - 5,000 Lux
Sunlight on an average day - 32,000 - 100,000 Lux
Labels: gardening, hydroponics
// posted by Erik @ 3/22/2008 12:28:00 AM
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