Rodenstock XR-Heligon 50mm f/0.75
A fast lens designed for use in medical X-ray imaging. It now serves as a tool for abstract flower photography, giving pictures with a unique dreamy character and superb bokeh.
The magnification ratio is slightly less than lifesize without additional extension and the depth of field is of course razor thin. This makes it quite challenging to compose pictures.
Please check out my Rodenstock set for some pictures using this exotic, and let me know if you like them ;-)