web analytics

Archive for October, 2009

My Heligon Lens Conversion

In my last article I’ve talked about the various Rodenstock Heligon lenses, with our interest being in their record-breaking speeds. I’ve also mentioned their incompatibility with an SLR because they can’t be mounted, and that I was waiting on the arrival of cheap extension tubes to overcome that :)


Toooobs!

Well, I’ve finally received the tubes and am ready to begin the process of fitting them to the lens so it may be mounted on an SLR.

So, what do you need?

A Rodenstock Heligon lens:

My Rodenstock Heligon lens

Note that you’ll need to pay close attention to its rear element and the dimensions surrounding it… more on this below.

Cheap extension tubes for your model of SLR:

Tubes

Here’s where I bought my Nikon version. Just search for extension tubes, and you’ll notice the ones below $10 all seem to be identical save for the mount that will attach to your model of SLR.

Epoxy:

Epoxy

I bought the LePage brand discussed below for $6 and it does the job (supposed to hold 350lbs of weight, matter of fact).


First, something important…

We’re going to adhere the tubes with the epoxy to the rear of the lens. Notice that you should determine the dimensions surrounding the rear element of the lens as the extension tubes need to be wider so they may wrap around it. As well, there needs to be some kind of base or plateau where the tubes can be adhered to. My 68mm Heligon is perfect for this as the tubes are the same circumference as the rear of the lens, and fit nice and snug. Check the image of me holding the lens above and you’ll notice its thinner, rear-end has a flat surface to which I’m able to adhere the tubes.


Step-by-Step Instructions:

1. The tubes come in a set of three individual rings that can be used in various combinations for macro shooting, as well as the ring that attaches to your camera and the one which accepts another lens. Remove the silver ring that attaches to another lens as it won’t be needed.

The Lord of the (tube) Rings

The Lord of the (tube) Rings

2. Place the series of rings over the rear of your Heligon lens to determine fit and see which rings are necessary for the best fit possible. The tubes are quite long as a set, and since the rear of the Heligon lens needs to be as close to your camera as possible, you may not need to use all the rings. For my 68mm Heligon I only need rings 1 and 2.

Rings 1 and 2, with the Nikon mount, ready to be epoxied!

Rings 1 and 2, with the Nikon mount, ready to be epoxied!

3. Now prepare your working surface, wipe clean the lens’ surface of where you intend to adhere the tubes, and whip out the epoxy. My choice of LePage epoxy requires me to mix resin and hardener before application.

4. Begin applying the epoxy to the lens’ surface from step 2 as well as the inner thread of the bottom-most tube that you intend to attach (don’t forget the mount-ring that comes with the tubes still needs to be screwed on to the other end!).

5. Let it sit for 8 hours and you’re done.

Tada!

Tada!

Gorgeous glass that needs cleaning

Gorgeous glass that needs cleaning


Some sample images from a walk through the park

Abstract 1

Abstract 2

Abstract 3

Abstract 4


Links of interest:

  • My introduction to the Heligon lenses.
  • Cheap extension tubes, sold by jiakgong DIGITAL which is where I bought mine. Search for macro extension tubes, and you will find plenty under $10 which suit our needs perfectly.

Thanks for reading!

Super-fast Lenses for Super-cheap!

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.


Roden-who?

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

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

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.

Look up!

Look up!


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.


Links of interest:

  • w8jsb sold me my 68mm f1.0. Highly recommended!
  • Cheap extension tubes, sold by jiakgong DIGITAL which is where I bought mine. Search for macro extension tubes, and you will find plenty under $10 which suit our needs perfectly.
  • A test of these ultra-fast lenses. My 68mm is in that list.
  • I’ve stumbled across a thread in which someone has accomplished the same conversion! Check it out for detailed pics.

Thanks for reading!