 Initially, for the first concept study, Compur was asked for a simplified shutter with a limited timing range of 1/30 sec to 1/125 sec, which, however, was not cheap enough for an effective reduction in production cost.Therefore, the first concept study got an immovable lens tube.The original movable sliding tube was one of the most expensive parts, because it had to be precisely manufactured on a lathe for a light tight fitting.