Pigment

Use pre-prepared 14 baume gum arabic solution to make the gum pigment mixture. Add 3 tubes of artist’s watercolor paint to 150 mls of the gum solution. Mix this solution well, lumps of pure watercolor pigment will destroy the print.

Sensitizer

The sensitizer is made from super a saturated potassium dichromate solution. Dissolve 25g potassium dichromate in 100ml hot water. Make sure to wear gloves dichromates are poison and have been known to cause cancer. The solid chemical will not fully dissolve. This means that the solution is fully saturated and is holding the maximum amount of chemical it can bare. When using this sensitizer do not shake. Use the solution without disturbing the crystals at the bottom of the container.

Mix the pigment and the sensitizer in the proportions shown above. Coat a sized piece of paper with this mixture. The coating should be thin and even. Dry the paper gently, excess heat will cause the emulsion to harden and become fogged, speckled and unusable. Most papers dry in twenty minutes depending on the papers absobancy, depth of the coating   and the darkroom's humidity. You'll know the paper is dry when the back is longer cool or damp and the paper wil crackle when bent.

Exposure

Expose the print by contacting under sunlight (approx. 5min) or an artificial light source high in UV (approx. 30-60 min). You may or may not see a brown printing out effect when the print is exposed.

Development

After the exposure place the print facedown down in a tray of cool water for about five minutes. Setup a second tray of cool water and transfer the print ( face down ) in to the clean water. Inspect the print periodically to judge when the soaking is complete. Place the print face down in an clean tray of water when the current tray has a lot of precipitated pigment in it. When you judge that the print has rinse out to the desired density, remove the print from the tray and air dry face up on blotter paper.

Notes