When I say fast, I mean fast. Try f0.75. And cheap? How about $20 on a good day when browsing eBay. And searching for cheap glass is exactly how I’ve stumbled upon the series of f0.75 to f1.5 lenses.
Manufactured in Germany by a company named Rodenstock, these lenses go by the names of TV-Heligon and XR-Heligon, and are designed for television and x-ray applications respectively. I’ve seen them range in focal lengths of 50mm to 100mm, with apertures rated at f0.75 on the short end to f1.5 on the long end. Some Googling tells me that upon failing to find suitably high-quality and fast lenses required for x-ray imaging in the 60′s-70′s, Rodenstock developed their own. With the advent of computing, however, the systems which utilized these lenses were no longer needed and so the lenses can now be had for quite cheap.
My 68mm f1.0 XR-Heligon
From x-ray machine to SLR…?
So what does this mean for us? You can’t attach a Heligon to an SLR as there’s no way to mount it (no screw threads, nothing), and even if you could the required distance of 7mm from the film plane means that it can never sit close enough to your camera sensor and so it’s relegated only to macro work (Nikon or Canon lenses sit 44mm+ from the plane plane). As these lenses were primarily developed for x-ray imaging, there is no need for a focus mechanism nor adjustable aperture (wide-open only). They’re also theta or so-called flat-field lenses and have a pronounced curvature surrounding the centre of the frame with an extreme of amount of chromatic abberations (purple fringing in bright areas). But that’s the best part!
Abstraction, as seen by an x-ray lens
Using a Heligon on your SLR is a perversion in every sense of the word and violates all known laws of physics. These were never meant to leave an x-ray machine, and even the lack of filter threads should tell you that. But don’t let any of this stop you from buying one. Here’s why:
I’ve discovered a $10 set of extension tubes that can be glued to a Heligon to use as a mount, for either Nikon or Canon. I’m awaiting their arrival in the mail. These are the exact ones I’ve purchased.
Being useful only for macro work opens a whole new world of photographic possibilities to those who haven’t shot macro before.
The lack of being able to focus isn’t important, as shooting macro requires lots of physical moving around anyhow.
Only being able to shoot wide-open? Well the fast aperture is the reason you’re reading this!
And best of all, the curved image circle surrounding the centre is like a Lensbaby on steroids. I will post example photos of this later.
After it was determined that this could eventually be mounted to an SLR, I promptly picked up an XR-Heligon 68mm f1.0 for $20 on eBay, as well as the cheap extension tubes so I may hack them into a suitable lens mount. I’m still waiting for the extensions tubes, but received the lens and have taken only a few shots when held against the camera. I must say, the optical qualities present themselves quite well on an SLR, for that dreamy, other-wordly macro look, and I highly recommend buying one.
The secret’s out! Pick one up on eBay along with cheap tubes and please stay tuned, as once I receive the extension tubes myself I’ll share instructions on how to make a Heligon fit your SLR.
This entry was posted by daifuku on October 2, 2009 at 11:59 pm, and is filed under Blog. Follow any responses to this post through RSS 2.0. Responses are currently closed, but you can trackback from your own site.