11 February 2011

A Simple Exercise for Judging Values

Trying to accurately record shape, value, edge, color, and temperature under the time constraints of an oil painting class is a big challenge.   In his book Oil Painting Techniques and Materials, Harold Speed recommends that students focus on only one aspect of technique at a time in order to master them all more quickly. For mastering the judgment of values, he recommends a simple 2-stage exercise.  The exercise sharpens the ability to see the large underlying value shapes that tie an image together and create the illusion of form.  It's based on the observation of values on a well-lit cast or simple still-life.  The subject is simplified into 3 values, then painted monochromatically as simple shapes.  Once this foundation is laid, edges are adjusted, and the smaller planes and details are added.  Dog before the fleas...forest before the trees. 

I've summarized the procedure here, in case you'd like to give it a try...
  1. The exercise requires white and any dark color that will produce a dark dark.  I used raw umber. 
  2. Set up your subject (a cast or something with minimal local color) in strong light to produce a variety of shadows. 
  3. Block in a simple charcoal drawing of the cast on your canvas.
  4. Study your set-up and decide on the value range, from lightest light to darkest dark.  Put a dab of paint with the lightest and darkest values in the appropriate spots on the block-in.  All other values will be judged in relation to these 2 extremes.  Squint down to judge.
  5. Lay in the background, ground and cast shadow as simple smooth shapes without detail.   Be sure to get the average values right.  Use thinned paint...you want to keep it lean at first.
  6. Now for the challenge...squint to reduce your cast to simple areas of shadow, light and halftone. Paint these value shapes on your canvas. 
    • The halftones are part of the lights, don't let them get too close in value to the shadows.   
    • Judge the shadow average by comparison to the darkest dark.  Never judge it by comparison to the lights or it will be too dark.  
    • Remember, it is not the edges of the objects, but the edges of the value masses, that make up the visual impression. 
    • Look for opportunities too lose edges.
  7. Carefully adjust all edges between value masses for correct shape and quality (ie. firm, soft, hard or lost.)
  8. The foundation is now finished, and it's time to add smaller planes and details.  Paint smaller planes as lighter or darker tones consistent with the larger value masses containing them. Carefully check each value you lay down.  Adjust edges as you go.  The image will only read well if small shapes subordinate to the big statement.
  9. Once you can consistently translate a cast or still life into a monochromatic value painting...add some color...the final frontier.
Here are a few of my results using some garden sculptures. Definitely helps with value judgment, but also targets edge quality and brushwork.  I believe it's improved my class work.  I'm more confident at the start, I know where I need to go...well begun is half done.
 
Final snail, 10 x 8 on canvas board
Snail caste painting at the "big shapes only" stage


Final rabbit, 10 x 8 on canvas board
Rabbit painting in big shapes only


I like Speed's closing comments on this exercise.
"Do less with your brush, and more with your head, at firstYou are like a raw recruit handling a rifle for the first time.  It needs a deal of thinking.  Afterward, at the word of command, the action becomes almost automatic.  And so with setting out your subject in simple masses...at first laborious, but eventually taking very little of your mental attention, which is freed to concentrate on higher things.  Concentrate on developing a perception of visual phenomena in terms of simple value masses."
 Added note:  As I was writing this entry, I ran across a post at Paul Foxton's blog on this same exercise from Speed's book.  My version is concise; Paul's is more eloquent and worth a read.


2 comments:

  1. Thank you, this is a very helpful summary. In publishing your blog you are providing a valuable resource for those art students who can only dream of ateliers...like me :) Keep it up!

    ReplyDelete