Monday, June 4, 2012

Light Spill

I had the morning free yesterday in Allentown, Pennsylvania so I set up my chair in an alley called West Silk Street and did this little gouache sketch.


I was interested in an effect that I've been calling "light spill." I've noticed this effect in old photographs or in pictures taken with a camera that has a dirty lens.

When an extremely bright field of light is surrounded by very dark forms, the light spills over into them. Even though those forms appear very dark near the sky, I tried not to paint them that way. The color of the light spill is the same as the color of the source of light, so a blue sky will spill blue light and a warm building will spill warm light.

I took some photos while I was doing the sketch. In these two details from the same high-key exposure, you can see the effect of light spill on smaller forms interpenetrating the bright areas. Note how the wires and the streetlight in the top detail are blue where they intersect the sky. The wires turn orange where they intersect in front of the warmly lit rooftops.

Photography has a disadvantage over painting in such super-high-contrast situations, because to really see the light-spill effect in the dark areas, you have to burn out the exposure in the light areas, which appear white in the photos above. 


But in the painting (detail above), I could hold some chroma in both the sky and the building. Gouache is a really nice medium for such experiments.
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Materials: Moleskine watercolor notebookWinsor & Newton gouacheCaran D'Ache Supracolor pencils
Color and Light book
Related previous posts:
Color Corona




14 comments:

jeff jordan said...

I'm just now getting into gouache and really LOVING it!

Kimberly M Zamlich said...

This effect makes for interesting negative and positive abstract designs...

Tomas Honz said...

Great image James.

Dave Lebow said...

a beautiful painting and really revelatory. I love how this looks, it is truly beautiful and I agree with the other commentors this effect and your excellent rendition creates a beautiful and interesting simplification and abstraction of the shapes and makes the viewer more aware of the design.

Celina said...
This comment has been removed by the author.
Celina said...

so neat to see a scene from my hometown! i saw you at a talk a few years back at the liberty bell church, were you doing something similar this time around?

J. R. Stremikis said...

@jim: wow. great work, and intriguing commentary. knockout posting.
you say, "Photography has a disadvantage over painting in such super-high-contrast situations, because to really see the light-spill effect in the dark areas, you have to burn out the exposure in the light areas, which appear white in the photos above."
regarding the use of HDR in this situation, and its potential to overcome the disadvantage... by chance, did you happen to put your camera in HDR mode? did that make any difference? (or, do you think HDR might be an advantage in these situations.) What do you think?

Anonymous said...

Excellent study, James! Do you mix gouache with watercolor when you do studies like these? Or, if you don´t, is your gouache portable set similar to your watercolor set, which those of us who follow your blog regularly are already familiar with?

Matt DIcke said...

Hi James
Great study. I was wondering if you would share what you use guache wise for travel sketches like this? Reading your posts using the water brush and Caran D'ache pencils really changed my way of working on location for the better. Haven't done it in year and your technique really sparked my love of location work again.
Thanks
Matt

Adam said...

That "light spill" looks a lot like chromatic aberration to me.

EZ Goodnight said...

I agree with Adam. In situations like that, or at least in that image, the color tinted edges look more like Chromatic Aberration. That is, certain wavelengths of light move at different speeds through the lens and diffract in peculiar ways.

It's possible that this is just a quality of that particular camera lens. Here's a simple article I wrote about Chromatic Aberration.

James Gurney said...

EZ and Adam, I'm familiar with chromatic aberration, and it does look like it at first glance, but in this case it's a different effect. You'd see it if you saw the whole exposure. Here, the color is flooding evenly across both edges of the small forms. The blue color on the wires in the upper detail is coming from the relatively blue light in the sky, and the warm color flooding the small forms in the lower detail is coming from the relatively warm light of the rooftops. In chromatic aberration effects you tend to get opposite colors on different sides of the form, like out-of-register color printing.

Scorchfield said...

dark side after moon, side-by-side, sunset? no, is sunrise on the streets!

Peace said...

Loooooooove this painting. I paint almost exclusively in gouache now, and I find that what Richard Schmid said about the medium to be particularly true. Namely, that gouache if used like oil, for both transparent and opaque applications is an outstanding medium, however if used solely opaquely, it lacks luster and is completely dead.

www.thepeaceartist.com