Does the color of sunlight change during the day?

[RyanSpaulding]

Hey guys,

 

I remember a while back hearing that the color of the sunlight changes throughout the day. Does anyone have any info on this? I'm looking for accuracy on some renders and this would help. Thanks in advance.

[Adehus]

These links might help some:

 

http://www.cybercollege.com/tvp028.htm

http://members.shaw.ca/jimht03/light.html

http://www.lightenergysource.com/kelvintemp.htm

http://www.insaneness.com/cgi-bin/kwrgb.cgi

[Andrew Schroeder]

Nice links, those are gonna come in handy.

 

To summarize them, yes, the apparent color of sunlight changes during the day due to atmospheric conditions in your particular location on the globe. Noon in Toronto, isn't the same as noon in Victoria.

 

What might be interesting is if anyone here has techniques for measuring or matching these physical colour changes for use in their CG imagery.

[Adehus]

Andrew-

 

I don't have any specific resources for that, but I think that the Maxwell renderer is interesting to watch from that perspective- I believe they're claiming that their app will account for all of the variables related to location, and will also allow for adjustment of turbidity, ozone, etc.

[Ernest Burden III]

Ask Claude Monet about his Rouen Cathedral series

 

Check out the little animated bits on this page:

http://acg.media.mit.edu/people/golan/rouen/Rouen_Images.html

 

and here:

http://www.mcah.columbia.edu/monet/swf/

[Tim Nelson]

Ask Claude Monet about his Rouen Cathedral series

I saw at least a couple of those at the Monet exhibit in Vegas last year, and I was so amazed at his work. I think it was probably the best exhibit I had ever been to because it focused on him alone and I really learned a lot about him & his work, and was especially impressed with his obsession with lighting.

 

I wonder how his work would be different if he lived in our time.

[IC]

The difference is he wouldn't be hung up about when it happened-just that it did and that he might be able to recreate it.

 

Surely the easiest way is to take photos and try to match the lighting you want/like by eye.

There are too many variables to try and calculate something like this. Maxwell works through maths not nature.

[silviapalara]

One tutorial I always keep handy is at

 

http://www.warpedspace.org/lightingT/part1.htm

 

But most definately try to take photos on location at the same time of day of your project, and if you are lucky, at the same time of the year. What I also do is in Photoshop to pick by eyedropper the color in the darkest and the lightest spot in my photos and keep those colors and values as references for my projects.

[vizwhiz]

hi There

 

Silvia

 

Thanks for the excellent link on Lighting

 

at the very bottom of This page There is yet another link to some more Lighting Info

 

it says:

 

I highly recommend THIS tutorial for a more in-depth look at lighting (by Richard Harris)

 

http://www.itchy-animation.co.uk/light.htm

 

quite Interesting, very useful

 

Thanks again

 

Randy

[Adehus]

Great links Silvia and Vizwhiz- thanks for sharing!

 

Andy