Moonlight SPD?

[TKM]

Anyone have an SPD of moonlight? I know it's quite like the solar spectrum;
but it's odd that it doesn't show up in the usual references on light and
color. I'd like to have both a curve and the relative data points.

Terry McGowan

 

[Don Klipstein]

Anyone have an SPD of moonlight? I know it's quite like the solar
spectrum; but it's odd that it doesn't show up in the usual references
on light and color. I'd like to have both a curve and the relative
data points.

My experience suggests visible portion is essentially sunlight filtered
to approximate a blackbody of somewhat lower color temp., with color very
much like that of blackbody and CRI almost certainly 100 or maybe 99.

As for color temp: My experience says usually mid-upper 3,000's, often
around 3800. Closer to zenith with especially clear air, appears to
me about 4000, maybe 4100 in especially favorable conditions.

- Don Klipstein ([email protected])

 

[Don Klipstein]

here are some:

http://www.astrosurf.com/buil/us/spectro10/sky.gif

To me, that does not compute - too similar to each other, both look to
me around upper 4,000's to maybe 5,000 K and a bit greenish, with moon
having close to same CCT as sky and slightly more greenish.

http://people.ucalgary.ca/~ccsunstr/images/GraphSpectraMoon.jpg

I come up with about 3650-3700 K CCT for that one - though it deviates
from blackbody somewhat by having more orange and less deep red than 3700 K.

Looks reasonable - I would at this point expect longer wavelength
portion of SPD to have a curve shape closer to that of sunlight, maybe
like mid-upper 4,000's K.

And here's a Google search page that has more spectra, and
perhaps more lunar spectra, but I haven't checked them all.

http://images.google.com.eg/images?hl=en&q=spectrum of moon&um=1&ie=
UTF-8&sa=N&tab=wi

- Don Klipstein ([email protected])