Light x Time: natural sunlight versus LED's?

[dshallpost]

Thanks to the generous and knowledgeable posters here I now understand a bit about artificial lights. For example, that recommended light requirements usually assume natural light with its morning-to-evening rise and fall with a peak at the "recommended" light level. Further, that when you grow under artificial lighting conditions the amount of foot candles can be lower because the light is constant, for a longer amount of time. Lower for longer.

But how to calculate how much lower? If, say, you plot foot candles on the Y axis and dawn to dusk on the X axis, you would get a curve that peaks at noon. How to translate the amount of light under that curve to a horizontal line, the LEDlight being constant from dawn to dusk (and maybe longer)

I just put up the first of three new LED fixtures (4 lamps, 4 feet each) The light is very, very bright, or so it seems to me. But a light meter registers about 1800 FC at the center about three inches below the lights. I was surprised. May-be I should throw away the light meter?

Would welcome thoughts about how to start with my orchids under these new lights, and how to "translate" from my window to this new environment.

[Optimist]

I believe it is calculus.

[terryros]

It works out to be 1/2. So, 1/2 of the recommended peak for the same total hours of light will give you the same “daily light integral”.

[Ray]

Simple trigonometry can give a close estimate.

Read this.

[dshallpost]

Perfect, thank you Ray!