• Turquoise and magenta make bright purple. Turquoise is not “too green” to make purple.
• Blue can be made by mixing turquoise and magenta, so blue cannot be primary.
• Red and blue make dark, muddy mixtures. (Red is the problem here. Any hue of blue or cyan will make a great purple as long as it is mixed with magenta, not red.)
• Turquoise and magenta are the more accurate primary colors. (If you want to split your primaries, you might try two cyans and two magentas; pigments PR122 and PB15:3 are excellent, but not perfect.)
Part 2: https://www.youtube.com/watch?v=dbcOcZw4g-I
• You can't make bright turquoise (or green) from blue and yellow.
• Turquoise and yellow make bright green. Turquoise succeeds where blue fails.
Part 3: https://www.youtube.com/watch?v=747uREIfnVg
• Red can be made by mixing magenta and yellow, therefore red cannot be primary
