This 4.9mm Hyperfisheye prototype lens is so wide it can see behind itself

LensRentals has posted some fantastic teardowns with impressive regularity over the years, but it’s rare that we see them put something together. They thought that it was about time to show off building a lens, after shooting timelapse of tearing down the massive C-4 Optics 4.9mm f/3.5 Hyperfisheye prototype lens from scratch, LensRentals founder, Roger Cicala posted a detailed write up of the lens being reconstructed from scratch.

Unlike most of the lenses today, this lens is all mechanical. There’s no fancy autofocus, image stabilisation or electronics to deal with. And that short 4.9mm focal length offers an insane 270° field of view. Yes, it can see behind itself!

This is the widest fisheye lens out there, by a very wide margin. The only thing that even comes slightly close is the legendary Nikon 6mm f/2.8, which offers 220° and costs well over $100,000 today. And most fisheye lenses “only” present around 180° to the sensor with rectilinear lenses falling well below that mark.

After stripping the lens down, construction is a slow and delicate process. A process which begins with glueing various lens elements together. After curing overnight, the real magic begins.

After building the barrel, the elements are added, and with each piece of glass costing around $5,000, they handle them extremely carefully. And once they’re all fitted into place, they’re held together by what they believe is the world’s largest lens retaining ring – I’m inclined to believe them! The thing is so big that it has holes for temporary screws to be able to hold and turn it.

But it’s not as simple as this. Oh no, there’s an entire frame that goes below the lens, which acts as handles to safely carry the lens with a camera attached. For small cameras like Sony mirrorless, they can fit entirely within this caged frame, although it is removable for use on larger cameras.

LensRentals does say that this lens probably won’t show up on their gear list for rental. It’s one of only two that were developed for C-4 Optics. And it’s very cool indeed. Roger says that the C-4 Optics 4.9mm f/3.5 Hyperfisheye is only for very special use cases and immersive video. But I’d love to see the kind of images and footage this thing can produce. They say those should be coming in a little over a week. I can’t wait!

Check out the complete build log over on the LensRentals website.

Photos used with kind permission of LensRentals.