I did this painting in oil on baltic birch 1/8th inch plywood. (Sealed and gessoed by me this summer on my back lawn under the supervision of Teena my tabby.) In case you're curious, here's the palette I used for this painting: Raw sienna, burnt sienna, raw umber, naples yellow, indian yellow, ultramarine, cerulean blue, cadmium red light, cadmium yellow light, pthalo green, flake white, and mars black.
For such an earthy grey painting it sure took a lot of colours. Most of the non earthtone colours were for the really saturated accents like the school signs (Pthalo green and cad yellow). Okay I used black. (I'm allowed to because it's my painting and I hate rules). Most of the "blacks" are done with a mixture of ultramarine blue and raw umber....but I couldn't resist getting the mars black out for the final touches...mostly defining some of the foreground shapes. I chose mars black over other blacks such as ivory because mars black drys faster. Same reason I chose lead white over titanium.