Here is my painted color study, just completed. It's small, roughly 5" x 13". I decided to use tube acrylic because acrylics can be more forgiving than watercolor and I wanted the freedom to change things up should I want to switch colors. I just may paint the final piece using acrylics!
I began by using the acrylic paint like watercolor and gave the entire paper surface a Yellow Cad. Light wash, including the birch trunks. I switched to Cad. Red Light, which is actually orange, and added a light wash while the yellow was still wet. I've never been happy with any tube orange but decided not to sweat the small stuff just yet. I knew I could adjust things later. I didn't bother masking the lower leaves for this study either. I just wanted to see how my chosen colors worked together. Once the yellow and orange were dry I mixed Deep Violet and UB to create various degrees of red and blue violet and laid in my darker values. Then it was all a matter of tweaking. At one point I was afraid I had gone too dark on the birch trunks but as I kept going it all began to work. Birch bark is so white it reflects color well, even in shadow...especially in shadow...which provided an excellent opportunity to bring some excitement to the trunks. I completed the leaves using mostly yellow and violet but hit a snag when I added Cerulean blue, my 'pop' color. Full strength it looked awful but mixed with a little white to soften it, it worked very well. I added the pale Cerulean to the background, some of the leaves and both tree trunks. To complete the study I toned the orange areas with a light wash of deep violet, very diluted.