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Friday, May 30, 2008

Avoiding Slipped Values

Sometimes I like to premix my values. I do this especially if I find a scene that might give me some trouble with slipping values. Such a scene is one where trees cast large areas of dense shadow surrounded by strong sun. The shadows usually show bits of sunlight breaking through. Also, a great deal of light bounces into these shadows from nearby sunlit objects. You may get a good fix on the value relationships initially, but as the sun moves, the bits of sunlight come and go, and the bounced light can get brighter or dimmer. Unconsciously, you perceive these shifts, and you will try to capture the change without realizing you are doing so. This can make for a painting full of slipped values.

Here's a demonstration I did yesterday. First, my premixed values. I don't usually use a paper palette, but I wanted to create a grid for my darks, mid-darks, mid-lights and lights. (You can click on any image for a bigger version.)

Next, here's the first layer of paint applied with a knife.

Finally, the finished painting. I ended up never getting to the brushes and did it entirely with a knife. Thanks to my premixed values, I was able to keep the values from shifting, and the painting represents the original values closely.


"Yellow Morning"
8x10, oil, en plein air