50mm f/0.75 X-Ray Lens Turned Into World’s Fastest E-Mount Glass

The Rodenstock XR-Heligon 50mm 0.75 lens is an old lens that was made for medical X-ray imaging by the German optics company Rodenstock. You can find them for sale on eBay these days for $50 and up.

Greek photographer Haris Antonopoulos and his buddy Thanasis Ioannidis recently decided to take one of these lenses and turn it into the world’s fastest lens for Sony E-mount cameras through a physical conversion.

For the conversion, the duo used a lathe in a metal shop to turn the smooth metal body at the base of the lens into a C-mount thread.

This allows the lens to be attached to a C-mount adapter, which in turn can attach to everything from Sony E-mount to Micro Four Thirds bodies.

“It will fully cover an APS-C sensor and it will provide a working distance of 40cm,” Antonopoulos tells PetaPixel. “The center of the lens is sharp and depth of field is near zero.”

Here are some sample photos captured with the Sony a6000 to show what this lens produces:

Antonopoulos says the trickiest part of this DIY project was finding a way to stabilize the lens on the lathe so that the thread can be properly cut into the body.

This is the hardcore way of using one of these lenses on a modern camera — other photographers simply use glue or some other means to attach the lens to a suitable adapter.