On previously prepared grey A4 pages, I first created a scale between orange/red to green/blue.
Using a cadmium red hue to start, i began added a emerald and ultramarine mix. This created a very dark tone so to combat this and make this scale have consistent tonal values I added titanium white. Shifting the colour to be a lot more visible.
I followed the same principle when creating the emerald to violet scale.
B-log 