Avg lux in sunlight?

Phaserburn

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What is an average lux reading in direct sunlight on a clear day? Anyone know? I've seen many references to the color temp of sunlight, but not lux strength.
 

MoonRise

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Clear sky luminance is about 5.16 cd/in2 (8 kcd/m2) with a color temp of 6000K. That is equivalent to 2332 lumens/ft2, or 25,101 lumens/m2 which is 25,101 lux. (lux is lumen/meter2).

Shifting to photgraphy knowledge, since there are about 2-3 f/stops (each f/stop is a doubling of light) difference between direct sun and clear sky lighting, there would be about 100,000 to 200,000 lux.

The sun puts out a LOT of light. Also some heat. /ubbthreads/images/graemlins/smile.gif
 

Phaserburn

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Found this, for your amusement:

Outdoors Conditional Illumination

(ftcd) (lux)
Sunlight 10,000 107,527
Full Daylight 1,000 10,752
Overcast Day 100 1,075
Very Dark Day 10 107
Twilight 1 10
Deep Twilight .1 1.08
Full Moon .01 .108
Quarter Moon .001 .0108
Starlight .0001 .0011
Overcast Night .00001 .0001
 

thesurefire

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[ QUOTE ]
MoonRise said:
Clear sky luminance is about 5.16 cd/in2 (8 kcd/m2) with a color temp of 6000K. That is equivalent to 2332 lumens/ft2, or 25,101 lumens/m2 which is 25,101 lux. (lux is lumen/meter2).

Shifting to photgraphy knowledge, since there are about 2-3 f/stops (each f/stop is a doubling of light) difference between direct sun and clear sky lighting, there would be about 100,000 to 200,000 lux.

The sun puts out a LOT of light. Also some heat. /ubbthreads/images/graemlins/smile.gif

[/ QUOTE ]


Does that mean that looking at the sun and looking at a 25,000 lux incan are about the same?
 

evan9162

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Nope, it means that looking directly at the sun would be equivalent to looking at a 100K-200K lux light.
 
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