Monday, January 18, 2010

Color Isolator

On Saturday’s post we looked at color constancy illusions, which prove how hard it is to judge a color note accurately. There are various methods to overcome the problem, most of which involve isolating a particular spot of color. One way is to look through the hole in a half-closed fist. Another is to hold up two fingers spread slightly apart and look between them.


Other artists have developed special viewing scopes for isolating colors. You can make one yourself by painting a 3x3.5 inch card half white and half black. Then punch a hole in each corner. Looking through those holes allows you to isolate a given color against white or black. You can also compare two different nearby colors through side-by-side holes. You can test a mixture by putting a daub of paint next to the hole.

The limitation of any such device is that the illumination on the scene may so far exceed the range of your pigments that no single one-to-one match is possible. A related problem is that the tone of the white card changes as the illumination on the card changes, so you have to hold the card exactly at the right angle relative to the light to get a useful comparison.

Previously: Color constancy.

9 comments:

Unknown said...

This is so interesting. It is such a metaphor in and of itself. IT seems to say that everything is relative. Color included. And we almost can't evaluate things for ourselves int he context of its surroundings. So fascinating to think of this in relation to greater concepts. Great post. (even if you were just talking about color)

Anonymous said...

What a splendid idea! I'll have to try this; I'm curious where I'll be surprised at the actual color.

Also, just wanted to say I've really been enjoying your blog; my boyfriend recently pointed me here since we're both tools-obsessed, and the wealth of artistic information astounds me. All the little bits here and there really add up and have me think in greater depth about my own art. Color is not my forte, but I hope someday to grow stronger at it.

Thank you for inspiring all us blooming artists out there. :)

My Pen Name said...
This comment has been removed by the author.
My Pen Name said...

Mark Carder has a 'color checker' which allosw you to put a dab of paint and check it against the isolated color

He emphasizes that it only works when the light on your subject and your work area is exactly the same.

It's not a panacea but a helpful learning tool. i don't own it but:
http://www.thecardermethod.com/store.html
looks like you could make one yourself fairly easily.

one thing i have found is that my pallet color throws me off far more than expected.

Charley Parker said...

It's astonishing sometimes how different an isolated color is from what you see in the context of the surrounding colors. Great topic. Thanks.

Larry said...

I remember coming across this guy on the internet years ago. It's meant for beginners and I can't imagine painting this way, but the color checker or isolator is a good tip.

http://www.thecardermethod.com/clips/overview.html

James Gurney said...

Thanks for mentioning the Carder method. Someone sent me a link a while ago, and I forgot his name. He explains the problem very well, and has come up with a clever solution. I think these devices work best for portrait or still life painting where the light on the subject and the painting can be carefully controlled.

thomas@thomaskitts.com said...

Another thing to do when painting en plein air, is to add a three or four more intervening value strips between the black and white. Three or four at most since that's all an artist needs in the field to mass the larger shapes.

Any more than six values may complicate things unnecessarily, or diffuse the painting's design. And who has time for establishing more than six values in a plein art painting when the light is in constant in movement anyway?

Great blog.

Thomas

http://www.thomaskitts.com

thomas valenti said...

Remember!! Very important. Not ALL reds, yellows and blues are PRIMARY COLORS. Just because a color has the word RED in it doesn’t make it a primary color. See for yourself. Mix Cadmium Red with Cerulean Blue. Is it violet as it should be? I think not. Try the same red with Ultramarine Blue. Not violet. Now. Refer to the colors in a full range of color printer. The colors are Magenta (Red), Cyan (Blue), Yellow (must be a LEMON YELLOW with no trace of green)
So. Translate this to either oils, watercolors or acrylics and the colors are : W/N Permanent Rose (as Magenta), (Grumbacher Finest) Thalo Blue (Cyan) and (Grumbacher Finest) Lemon Yellow. There is a color by Holbein named Opera Rose. It’s way closer to a true Magenta it is however considered to be a fugitive color which may be prone to fading. I ran tests which exposed colors for 3 years to an east skylight with strong sun. (I painted a 1” wide by 12” long strip of paint. Then I cut it in half and put one strip in a drawer the other in the sun and waited three years) Opera Rose being one of the colors and I could not detect any difference from the drawer kept strip.