"Red Rocks" sketch - 9x12, oil - $100 - contact Michael
Beginners will sometimes end up with a lot of chalky color in their paintings. The chalkiness always appears in the light colors, and therein lies the key. In order to make something lighter, the beginner adds white. White is the "killer color." It not only lightens, but it also cools and dulls color. Too much added white will make a color look chalky.
If you use a split-primary palette, you'll note that your colors are laid out in color wheel-fashion. Cool and warm versions of the primaries go from yellow on left to red and then blue on the right. (See my recent blog post on my palette to see a picture.) To lighten any color mixture, find approximately where it sits on the color wheel and then add a bit of lighter and thus warmer color from the left. For example, if you make an orange - cadmium yellow medium plus cadmium red light - and it's not light enough, lighten it with white, but then warm it up again with a touch of cadmium yellow medium or even cadmium yellow light. (You'll have to experiment.) Anytime you want a warm mixture, if you add white to it, you'll have to add a warm light color to it to warm it back up.
One word on white. Some whites are warmer than others. Going from warmest to coolest: flake (lead) white, followed by titanium white and then zinc white, which is the coolest. For a very warm white, I have sometimes used a very light tint of Naples Yellow instead of white.
By the way, if getting a really pure orange is your problem, it'll be hard with the split-primary palette. It's impossible to mix rich secondaries. You'll need to buy a tubed orange, such as cadmium orange. The richest secondaries are always tubed colors. For my secondaries, I like cadmium orange, dioxazine violet (or purple), and phthalo green. If you're interested in secondaries, it's important to remember that, just as with the primaries, there are cool and warm versions of each. Conceivably, you could create a large but very workable palette that incorporates cool and warm versions of both the primary and secondary colors. It would have 12 colors.
At the top is a painting I made recently with cadmium orange and in which I tried to avoid chalky color.