"I can't mix color!" Over the many years of teaching oil painting, this is one of the most frequent statements heard in my art class. I'm afraid that there is no magic solution. In order to solve this problem you need to do some serious studying and application. I gave my students homework that would rectify this problem and the students who applied themselves saw marked improvement. There is always the student who "didn't have the time" or didn't want to make the effort and they are the most difficult to teach.
Good painting is a balancing act between shapes (drawing, edges, linear perspective), tones (the five tone values, aerial perspective) and color. Shapes and tones give us a monochromatic painting. Color adds the magic. Isn't that a good reason to learn more about color mixing?
This is a slow, deliberate and time consuming exercise. The amount of effort you put into this will determine your results. I think it's a fascinating exercise.
Let's start with purples. We know that red and blue make purple. That's easy enough. But what red and what blue? You have to visually experiment. Put out all your reds and blues and begin to experiment with mixtures. This is the only way you will see the differences. Cad Red Light and Cerulean Blue will give you a different purple than will a mixture of Windsor Red and Ultramarine Blue.
As you experiment with different red and blue mixtures, begin to add bits of their complements - green (red's complement) and orange (blue's complement). Don't forget yellow (purple's complement). Add small amounts of complements to separate mixtures and compare the results. Notice how the temperature and hue change. Add white to lighten and note the results.
Take your time and keep your mixtures clean. Make all the possible color combinations you can and mentally note the results. Some people like to make color charts, that's fine, but I never did. Your color mixtures will vary by the amount of each pigment you add and that amount is variable unless you measure. Visually experiment and understand the why of your mixtures. Soon you will be able to mix colors by sight and not formula.
Purple is one of the three secondary colors on the color wheel. Try this exercise with the other two secondary colors - orange (mixture of yellow and red) and green (mixture of blue and yellow).
I also suggest playing with your colors at the end of your painting session. Instead of scraping them away, take a few minutes to mix different colors together. Try mixtures that are unfamiliar to you - you will be surprised at the variety of colors you can mix.
I hope you will take the time to experiment with your colors. You will be amazed at the number of colors you can mix from these combinations. Notice that using a limited palette of colors will improve your color harmony and that most colors straight from the tube are too harsh to be used alone. Work slowly and study the results. Then you won't have to say, "I can't mix colors!" and your art teacher will sigh with relief.
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