Here is list of some of the main colours I use: ultramarine blue, permanent blue light, cadmium red middle (sparingly, and good for mixing), cadmium yellow middle (sparingly, and good for mixing), naples yellow, titanium buff light, or unbleached titanium, titanium white, prussian blue, chromium oxide green, hookers green, sap green, viridian green, ultramarine violet (great for cutting the saturation of greens, and for achieving more variety with blues), burnt umber, raw umber, I also use a variety of mixed colours,packaged in tubes, often not expensive...like light portrait pink, greyish blue, light blue violet, neutral grey...(they are great for tinting other colours). carbon black (great for mixing greys and allows to you easily achieve both warm and cool greys). The dark blues and greens are great for mixing the equivalents of black when mixed with the umbers.
I use the carbon black mostly to mix greys, but for a variety of extreme darks in the painting I use my darkest blues and greens mixed with the relaltive complementary....I love mixing darks! So for dark green masses I might use hookers green + prussian blue + burnt umber.
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