Video: How photographic salt prints are made

The George Eastman Museum has shared a video explaining how salt prints are made with a step-by-step illustration from its Historic Process Specialist, Nick Brandreth. The video lists off the ingredients needed and then demonstrates the process and the result. Nick also provided the video on How to safely make a 35mm daguerreotype at home that we wrote about last week.

Nick commends the process to beginners as it uses one of the most common chemicals found in any domestic kitchen – sodium chloride, or table salt – and says that this is one of the earliest photographic processes. He then goes on to say that we also need silver nitrate, bees wax and lavender oil, which may not be quite so readily to hand for most of us. He also treats his print with a toning bath of gold chloride, but in the comments of the video points out that this isn’t an absolutely necessary step.

The instructions tell us to dissolve the salt and silver nitrate in separate dishes of distilled water, and then to coat art paper with the salt solution. Once dried the paper is coated with the silver solution, and when that is dried it can be placed in contact with a large negative, either from a large format camera or one printed using an inkjet printer onto sheets of clear material, such as acetate.

The paper needs to be exposed to UV light so a good bright day or a UV lamp indoors will do the trick. You can inspect the print by eye to monitor its progress, and when it is done it is washed in tap water, fixed and dried. Nick then uses a mixture of bee’s wax and lavender oil to protect and seal the surface of the print.

Some of the finer details of the process are missing from the video, such as the quantities of salt and silver nitrate used, so in the end it is more of an overview than an instructional piece. However, Nick answers some of those questions in the comments and provides his email address for anyone wanting further information.