This was a very informative meeting with the technology curator at the National Museum where she removed this camera from display so I could get a close look at it. While unable to remove the lens or the front standard, eventually I spotted the light going into the lens just right to see just how they had designed it to make 3 colour separations in one exposure. Ingenuous, and I am looking forward to researching this more… and perhaps building my own. I have also included the list I was supplied with that shows other objects in the collection that I will be able to go review.