Making Cyanotype Prints

サイアノタイプ (青写真・日光写真)

These are simple photographs called photograms that are made without the use of a camera, instead objects are put directly on the sensitized paper and exposed with sunlight. A photogram is one of the simplest forms of photography but it can be challenging to make it look the way you want.

フォトグラムと言われるこの写真は、カメラを使わずに対象物を感作した用紙に直接置き、太陽の光で露光させるという技法を使っています。フォトグラムは最もシンプルな技法と言われいますが、望みどおりの結果を出すことは、なかなかの挑戦です。

Stock Solutions
  • Potassium ferricyanide (III)
  • Ammonium iron citrate (green) (III)
  • Distilled water
  • 2 containers, 500 ml each
  • scale 0.01 g precision
  • graduated cylinder, beakers
  • A4 recycled paper for holding chemicals on scale
Exposing
  • Sized watercolour paper
  • Contact printing frame or glass and wood backing with clamps
Developing
  • Trays for holding water and paper
  • rubber gloves

Solution A (Postassium Ferricyanide)

  1. Pour about 400 ml distilled water into beaker.
  2. Weigh 100 g of postassium ferricyanide powder
  3. Slowly add to water while mixing.
  4. Add water to make 500 ml
  5. Store in darkened and labelled container.

Solution B (Ammonium iron citrate)

  1. Pour about 400 ml distilled water into beaker.
  2. Weigh 40 g of postassium ferricyanide powder
  3. Slowly add to water while mixing.
  4. Add water to make 500 ml
  5. Store in darkened and labelled container.

To coat one A4 sheet use about 12 ml

In a dim room with no UV light:

  1. Draw faint borders with an HB pencil for the area to coat.
  2. Mix equal parts of solutions A and B (6 ml each)
  3. Pour into short and wide container for brushing on.
  4. Or pour 12 ml out onto centre of paper.
  5. Brush evenly and carefully to edges of border drawn on your paper.
  6. Dry slowly for 30–90 minutes in near darkness. Make sure there is no UV light, for example LEDs emit weak UV.
  1. Create your artwork by placing objects into your contact print frame
  2. Clamp the glass carefully onto the paper, make sure everything is holding steady and the paper is as flat against the glass as possible.
  3. Take the frame outdoors into bright sunlight.
Exposure estimates for summer in Kyoto (35º North)
  • Clear and sunny summer: 5–10 minutes depending on thickness of glass
  • To expose through leaves, increase time to 30–45 minutes
  • On an overcast day or late afternoon, try 45+ minutes for the basic exposure.
  • In clean water, rinse the print for 2–5 minutes
  • Change the water in the tray and wash another 10 minutes
  • Change water for a final rinse. If no more blue is coming out, dry the print.