Expanding upon the idea of the acetype as a simple method of obtaining a positive, one-off image, I hypothesised that the same might be possible on paper, and after a few experiments it’s clear that not only is it possible, but it is capable of creating beautiful and unique results.
To make a fibrotype you will need to coat your standard photographic paper with light sensitive emulsion, but before you do that you have a number of options. The reason for using silver gelatine paper as the base is twofold: firstly, the emulsion of the paper provides a reliable way of getting the emulsion to adhere without having to size the paper beforehand, and secondly the ability to expose and develop the paper, as well as tone it afterwards gives you the freedom to create a range of different colours and effects when combined with the liquid emulsion that will lay on top.
One method for preparing the paper is to expose it to the white light of the enlarger and then develop it in order to get a maximum black, in which case it will have to be correctly washed and dried before applying the liquid emulsion. If you want to tone this black base you will also have to fix the paper, but if not, fixing is not necessary. Of course, you can tone the final image, which will affect both layers of emulsion, but toning the base first allows you to selectively do so.
You can also take a fresh sheet of paper and allow it to print out in the sunlight which can give you a range of colours that normal exposure and development cannot achieve, and once again, this paper can be fixed and toned, or simply have the emulsion applied directly.
The simplest way of using this process is to expose the paper to enough light so that when developed it will produce a dark tone, and then without developing the paper apply and dry the liquid emulsion. What you are left with is a white base that has been pre-exposed, with a completely fresh layer of unexposed emulsion on top. This paper can then be used in camera as normal, or can be used under the enlarger to make positives from slide film. When placed in the developer the base will turn black and the silver image will develop on the top layer of emulsion. It can often be difficult to see the positive when the photo is laying in the developing tray, and will need to dry completely before it can be seen in the right light. Additionally, due to the thick layer of emulsion, the development and fixing times will need to be increased to allow the solutions to penetrate the base layer.
Unlike with the acetype process, unfortunately there is no speed gain when using liquid emulsion to make positive images in this way, which means that fibrotypes must be shot at around E.I 3, and would, like any other direct paper process, benefit from being pre-flashed under the enlarger in order to obtain more shadow detail.
Using a variable contrast emulsion is recommended for it’s flexibility, whether you are making unique, in-camera images like these, or printing directly from slides.