Prussian Blue sets the weight of the palette in trust and stability, and Rag Paper is the swatch that breaks rank: a single orange that stops the set reading as one note. Prussian Blue to Rag Paper spans 76 points of lightness, so the palette can carry its own hierarchy without reaching for a second one. Rag Paper and Prussian Blue sit on opposite sides of the temperature line, which is the tension the palette runs on and the pair to hold apart.
Prussian Blue a deep navy or midnight blue, trust deepened into authority and gravity.
Cyan Print an electric or cobalt blue: trust with real conviction, confident rather than passive.
Mid Exposure is the most trusted color in color psychology: competence, stability, calm, used constantly by institutions that need to be believed.
Bleached Highlight a pale sky blue, calm without weight, open, breathable, unguarded.
Rag Paper a peach or apricot tint, all the friendliness of orange with none of the volume.
Sun-printed iron chemistry: Prussian blue grounds, white silhouettes and brushed edges, from Anna Atkins's algae to contemporary botanical prints
Explore the full Cyanotype Photography style guide