Friday, February 1, 2008

Downfacing Planes

Most of the time we think of shadows as blue. Surfaces in shadows do tend toward blue if they are facing upward beneath an open stretch of sky. We can make a general rule if we hedge it a bit: “Upfacing planes in shadow are relatively blue on a sunny day.”

In the sketch of the library in Millbrook, New York, I observed plenty of bluish color in the cast shadows on the sidewalk, for example.

But planes in shadow that face downward are different because they pick up the warm reflected color of illuminated surfaces below them. You can see this effect in the white pediment. Where the projecting forms faced downward, they’re distinctly orange, not blue at all.

So let’s revise that quick rule of thumb about the color of shadows: “In shadows, upfacing planes are cool, and downfacing planes are warm.“ If you click on the photo above, taken at Bryce Canyon by Tobey Sanford, you can see the cool upfacing planes (1), and the warm downfacing planes (2). What you can't see are my knees shaking.

Tomorrow: Baseball Cap Space Helmet


nn said...


Anonymous said...

awsome painting james!

Tomorrow: Baseball Cap Space Helmet

ohhh lord i cant wait!!!!!

indiaartist said...

Cool. You have a knack for making it simple. Looking forward to next posting. Thanks.

gail said...

What a simple thing to remember, yet have a huge impact!


Dan Gurney said...

The photo really illustrates this point well. Was it taken for the Life Magazine article about Dinotopia I?

James Gurney said...

Yes, the LIFE photographer, Tobey Sanford, followed me all over Montana and Utah on a painting/dino dig expedition, and he and became friends. Some of the recent posts on lighting have come from conversations with him.

Rose Welty said...

Thanks for another great post - it's very helpful to have it simplified for those of us that find this sort of thing very difficult. Can you recommend any sources on seeing colors?