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Photographic Printing, How to Create a Real Salt Print

Updated on May 23, 2012

Alternative Photography

Salt Print, Parndon Lock
Salt Print, Parndon Lock

Alternative Photography

How to Make a Real Salt Print

The major breakthrough in the development of the modern photographic process came in 1835, when William Henry Fox Talbot, F.R.S. had a eureka moment and realised how to produce, on a support, silver chloride, the silver halide he needed for crisp, clear photographic prints. Some have suggested that moment came in 1833 when on his honeymoon!

Unlike the cyanotype process, salt printing is not cheap, although not as expensive as platinum printing; it is safe when adhering to strict chemical safety processes.

Remember the safety precautions with chemicals, rubber gloves, goggles, don’t get chemicals in your mouth, wash your hands, don’t work on food preparation surfaces; don’t eat, drink or smoke whilst using chemicals, most importantly:

it is definitely not for children.

As one would expect, salt (sodium chloride) is one of the chemicals required; however, ordinary table salt won’t do as it contains anti-caking chemicals that will interfere with the process, the best salt to use is sea salt or cooking salt, some use seawater.

Silver nitrate is the light sensitive chemical needed, but it only produces a thin, grey image, what is needed is silver chloride, but that has no solvent to allow coating on to a support. In a flash of inspiration, Talbot came up with an elegant solution to the problem and gave us negative/positive photography.

Silver nitrate is toxic if swallowed, corrosive, and stains.

[Haz class-5.1/22B]

Citric acid is needed as a preservative for the silver nitrate solution.

Use Hypo (sodium thiosulphate)to fix your print, not general photographic fixer, which is too aggressive and will bleach your print.

Sodium carbonate (washing soda) to make the hypo more alkaline.

Like cyanotype, salt printing is a contact print process, so the main disadvantage is obtaining large enough negatives. I use a 5x4 film camera and contact print from the negatives it produces. If you have a 35mm or medium format camera, you will need to scan, or get scanned, the negatives to print out large negatives on overhead projection film (OHP). If you have a digital camera, the chances are you already have image editing software on your computer to create negatives with OHP film. It is possible to make negatives on ordinary writing paper, Talbot made his by putting sensitised paper into his camera, of course, we use an inkjet printer to print our scanned neg.

The method, and that elegant solution:

You first need to salt the paper; cheap drawing paper will do as long as it is strong enough to be soaked. I use Saunders Waterford 140 lb watercolour paper, hot pressed or NOT (cold pressed) surface. Mix 20grams of salt with 1 litre of tap water to make a 2% solution. Pour this into a watertight tray large enough to take the paper size you’re using.

Put a small mark on the back of the paper and then soak the paper by immersion; dry the paper with a hair dryer. This operation can be done in normal light.

In a graduated chemical measure, mix 12g of silver nitrate with 50 ml of distilled/purified/de-ionised water, NOT tap water, the solution will react with the chemicals the water authorities add to the water. Keep to one side. In another chemical measure, mix 6g of citric acid crystals with 50ml of distilled/purified/de-ionised water, when they are both fully dissolved, mix them together and store in a labelled, brown bottle. Pour a small amount of this liquid into an old, never again to be used for food purposes, saucer and brush on to the front of the salted paper. Dry the emulsion off with a hair dryer and tape to it, along one edge, your negative, sandwich this between a piece of hardboard and a sheet of glass, fixing with bulldog clips. The whole operation to this point with the silver nitrate is carried out under normal tungsten lighting or daylight with the room curtains closed, no fluorescent tubes or TV light.

You now have on your paper:

sodium chloride

silver nitrate.

The chemicals will react and give you:

silver chloride

sodium nitrate

Clever wasn’t he?

Put in the sun, or in front of a UV light source, and check by unclipping and lifting your negative, say, every three minutes until the tones look right.

Wash/develop the print under running water for about five minutes, until the water turns from milky and runs clear.

Fix in a mixture of 25g sodium thiosulphate, 2g sodium carbonate and 500ml tap water.

Wash for half an hour.

Like cyanotype, salt prints are as permanent as the support the are printed on.

Have fun.

I have no control over how you may carry out these operations, as I said earlier, it is not for children and silver nitrate is a hazardous chemical, you are responsible for your own safety.

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    • Dolores Monet profile image

      Dolores Monet 8 years ago from East Coast, United States

      Interesting process. I have a son who is interested in alternative photo processing and must ask him if he has tried this.

    • MickS profile image
      Author

      MickS 8 years ago from March, Cambridgeshire, England

      Watcha Dolores

      thanks

      best Mick

    • ethel smith profile image

      Eileen Kersey 7 years ago from Kingston-Upon-Hull

      Wow. You can tell you are knowledgable on this subject

    • MickS profile image
      Author

      MickS 7 years ago from March, Cambridgeshire, England

      thanks Ethel

      best

      Mick

    • profile image

      eric 7 years ago

      good bit of instuctional material

    • MickS profile image
      Author

      MickS 7 years ago from March, Cambridgeshire, England

      Thanks Eric

    • profile image

      Ivanders 3 years ago

      Good info you got here, thanks !

      But one question,

      How long those the print need to be on the fixer ?

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