Using a Harman TiTAN Large Format 4x5 pinhole camera with Ilford FP4 film and the required filters meant long exposures ranging from 2 to 4.5 minutes. The movement of the tree shadow over the time of the 3 exposures has created the rainbow in the foreground. I assure you this was intentional, however it turned out considerably better than I had hoped! Creating this was difficult. Taping filters to the camera, dropping film, filters and light meters on the woodland floor and making sure I used the correct holders was nerve wracking. Worth it though!
Trichrome images are made up of 3 separate black and white negatives each made with one of Red/Green/Blue filters. The negatives are then scanned and a new single digital image created using the scans as the RGB channels. The final colours are greatly influenced by changes in the scene during the three exposures. Wind, light levels, additional in camera filtering are all used to create different effects.