Category: Uncategorized

• February 12, 2026

  LIGHT

  Light is the catalytic variable in cyanotype, driving the photochemical reduction of ferric iron (Fe³⁺) to ferrous iron (Fe²⁺). Ultraviolet wavelengths are primarily responsible for initiating this reaction, meaning exposure intensity, spectral quality, and duration directly determine image density and tonal separation. Insufficient UV results in weak, low-contrast prints, while overexposure compresses highlights and reduces…