Have you noticed that when I plein air paint I tend to use “Artist’s” quality paint, like in the case below — M.Graham. This is because when plein air painting there already is enough that I am fighting against, I do not need to fight against the paint. When I paint in the studio I tend to use “Studio” quality paint. This lower quality paint is OK, because in the studio I have the time to modify the paint with lots of medium and prepare it to the glistening quality I desire. Below is my typical plein air palette now.
Raw Umber [PBr7], for sketching & “detuning” underpainting.
Titanium White [PW6, PW4], for lightening colors.
Mud [mix of Cool Blue, Cool Yellow, Warm Red], for darkening color.
Double Primary Colors…
COOL BLUE == Ultramarine Blue [PB28]
WARM BLUE == Viridian [PG18], this is not the hue.
COOL YELLOW == Hansa Yellow [PY3]
WARM YELLOW == Cadmium Yellow [PY35]
WARM RED == Cadmium Red [PR108]
COOL RED == Anthraquinone Red [PR122], (Winton=Perm.Aliz.Crimson)
According to most watercolorists, the COOL colors in this list are the primary colors.