Glass Cyanotype

I have been wanting to do this for a long time, but it seemed like a very difficult technique. In fact, it was quite easy!

The general idea is to coat glass with the same photographic emulsion used to make cyanotypes on paper. The problem to be overcome is that the emulsion has nothing to adhere to and would just run off the glass. The common solution is to use Gelatin as a size.

The gelatin was prepared by soaking 2 packets in 500ml of water for 15 minutes. It was then heated to 140-160 degrees Fahrenheit for 2 minutes. This was then mixed 1:1 with the standard cyanotype emulsion. I used 10ml of emulsion and 10ml of gelatin. This is poured onto a VERY carefully and completely cleaned glass plate. The emulsion is rolled around until the plate is coated. Amazingly, with careful tilting, the liquid does not roll over the sides. The excess liquid is poured off the corner of the plate back into the pot or into a paper towel. The plate is then set to dry. I have seen this process done under safelights, but as with paper, I did it under dim florescent light and the highlights cleared very well.

Once dry, the plate is exposed in very much the same way as a paper print.

The development is all done in water but clears very quickly.

I did a 30 second soak. When the plate came out and was set to dry, it ran blue chemical off into the paper towel. I think this is normal.

The second development bath is a bit more aggressive with light agitation.