This project is an ongoing collaboration with London-based photographer Sue Barr. Together we are using only two spot colours to see how closely and accurately we can simulate a four-colour impression. In order to do this, Sue’s photos need to be altered to a two-colour chromatic construction. The chromatic construction works according to the law of subtractive colour mixing. All achromatic values in a picture are created by the fact that subsets of the coloured printing inks neutralise each other and form achromatic values.
![](/sites/default/files/2020-06/suebarr-4.jpg)
Pantone 286C colour separation.
Through colour separation, image editing and colour profiling, the individual colour separations of the photos were processed.
![](/sites/default/files/2020-06/suebarr-5.jpg)
HKS 68K colour separation.
Close but not yet perfect. We are still working on getting closer to the original.
![](/sites/default/files/2020-06/suebarr-3_0.jpg)
Different print sequence. Above: first HKS 68K and then Pantone 286C. Below: the reverse.
![](/sites/default/files/2020-06/suebarr-6.jpg)
The original image.