I'm still working on my colour charts off and on when I get a moment. Yes, they are time consuming, yes they take some paint and some work, but yes they are worth the effort. Nothing helps you become so familiar with your palette as does the process of finding values that you can achieve by pushing paint around.
This is the third chart still using my split primary palette. This time ultramarine is the dominant colour and mixed across the top row with each of the other colours then downwards in ever increasing amounts of titanium white to decrease the value as I go.
Ultramarine blue is the workhorse of many palettes as it is versatile, cool, transparent and powerful. Its bias leans towards red so mixed with yellows, either cadmium lemon or cadmium yellow light here, the greens produced are less saturated than the mix I'd get with Pthalo Blue and Cad lemon for instance. You can read everything you need to know about ultramarine pigment on the Winsor & Newton site.
Titian made dramatic use of ultramarine in the sky and draperies of Bacchus and Ariadne (1520-23).
With the reds, the range of purple and violets in pronounced with a richer version in alizarin crimson and permanent rose as they have some blue in them giving a more saturated colour than when mixed with Cadmium Red Light has a yellow bias and desaturates more towards a purplish grey, which I quite like.
Four value ranges, from left to right, mixing pthalo blue, burnt sienna, burnt umber and payne's grey with ultramarine and titanium white.
When mixed with the earth tones, chromatic blacks can be created, leaning towards browns in the Burnt Sienna, charcoal greys with Burnt Umber and blue-greys when using Payne's Grey. Payne's Grey is a mix of Ultramarine, black and a little burnt sienna, so staying within that family a harmonious palette is created.
Next I will be looking at blacks and greys, both straight blacks and greys from tubes as well as chromatic blacks, which I prefer as they have more warmth and interest in them.
As a note, I have used mostly KAMA pigment oil paints in the colour chart and heavy weight Bristol paper 400 series 11" x 14" applied with a palette knife.