They're both similar in a lot of ways: opaque, matte, water media. The main difference is that casein dries to a more closed surface, meaning the dry paint doesn't reactivate when it's wet. Gouache can be reactivated.
|Alaskan Wolf, gouache, 5 x 8 inches.|
When I painted this Alaskan wolf in gouache yesterday, I used black and white casein for the background. Once I laid the background down, I didn't want it to change too much.
I chose gouache for the wolf because I wanted to be able to reactivate it. That was the only way to get the softness of the fur, especially in the shadows, like under the mouth and on the neck.
To do that softening, I re-wet a postage stamp size area with a flat brush dipped in pure water—really quick, no scrubbing! With a rewet surface, I could gently coax out softness with another brush or with my finger, or I could drop in a stroke that would blend into a blur.
(Use this link to view video on Facebook) Where I wanted fine details of fur in the lights and the halftones, I used gouache in a more dry-brush mode, and I used a few touches of light and dark watercolor pencils.
Expand your GurneyJourney Reach:
James Gurney on Instagram — Daily serving of color, light, and Dinotopia
My public Facebook page —Where you can see short videos that don't always appear on YouTube
Gurney on YouTube — Almost 200 free videos, fun and instructional.
Taxidermy by: Lynn Stewart
Event: SKB Workshop in Dubois, Wyoming / 5 days, 15 instructors, 150 students.