Shooting chromatic photographs is somewhere between normal photography and pinhole photography. Normal in the sense that you use normal film and a camera to take the three primary images, but like pinhole because the effects of time become evident in the picture.
A pinhole photograph on photographic paper has a long exposure and the time effect is that moving elements of the picture tend to disappear . Take a look at the pinhole image below- it was really busy on the sea front the day we took this picture – but all the fast moving people are invisible and the slower ones look ghostly. Nice!
The time effect in a trichromic picture comes from the time it takes to change the camera filter – or the pause you can take between one primary colour image and the next. In this image the people on the pier changed while I changed the colour filter – the camera was nice and steady giving a good colour image – and the movement of the people produces yellow and blue ghosts! Great!
Or this example – where I waited for the traffic light to be red each time I took the next image. The lights are red but the cars and people are a great colour mix. The animated gif file above shows how changing the hue values in the image reveal the three contributing red, green and blue images.
