This, like the Isco-Göttingen Westar 75mm f2.9, was a “fast” option available on several German turret and folding medium format cameras. This lens is somewhat similar in look to the Westar, but it has an interesting characteristic, which is that as the lens is focused (using its own focusing mechanism incorporated into the lens) it totally changes the bokeh characteristics of the lens. When set to infinity (and then appropriately focused using a helicoid) the bokeh is quite hard and bubbly, something like the famous Trioplan lens. But as the lens is set to closer focusing distances (which moves the front elements away from the rear elements) the bokeh becomes softer and softer, until at the minimum focusing distance the look resembles a soft-focus lens with very smooth bokeh.
