Great conversation all around! I may be misunderstanding your point, waterholic -- but per Epicurus the atoms are colorless and perception of color is relative.
Scholion on Epicurus, Letter to Hēródotos, D.L. 10.44: He says, moreover, that there is no quality at all for the atoms except for shape (τὸ σχῆμα), dimension (τὸ μέγεθος), and weight (τὸ βάρος) – that color varies with the position of the atoms, he states in his Twelve Elementary Principles.
Plutarch, Against Kōlṓtēs, 1110B: Epicurus himself in the second book of his Reply to Theóphrastos, says that "colors are not intrinsic to bodies – but a result of certain arrangements and positions relative to the eye."