Fourth (unusual) type of Rodenstock Heligon, circa 90mm

alex ph · Joined: 16 Mar 2013 Posts: 1674

Fast industrial Rodenstock Heligons are well explored in the last years in different photo forums. After having read several sources, I conclude the most wide spread are three main types.

1. XR-Heligons, varying from circa f50mm to 120mm with a very short distance to focal plane, which are mostly "dreamy". A 100mm sample from this forum.

2. TV-Heligons, which are the complement of the previous ones in X-ray equipment, equally fast, very short flange and "dreamy". A 75mm sample from the forum.

3. 1.6/100 Heligon, quite a different lens praised internationally, long enough flange for adaptation on digital, fast and sharp. Sample shots in this forum.

I presume I stumbled upon a fourth type, which was not previously described.

Physically Heligons may be present in quite various bodies, sometimes inscriptions are put on the side or hidden under the helical tube. So the task of identifying the type with a simple glance at the barrel is not a banal one.

When I saw a good offer of Heligon which did not look in a usual way, I was intrigued. Barrel inscription was only saying the lens name and its serial number, nothing more. There is also a scale going from 1 to 9, but its presumable "focusing" destination was under question.

When I received the lens, first point of curiosity was its original box. It looks like that, hinting the lens' usage for an optical rather than X-ray machine.

The weighty helical tube taken off, the lens revealed no more inscriptions. But turned out to have a 41mm outer barrel. A perfect fit for an M42 helicoid!

One turn of sticky tape, and it enters tightly inside. The flange is quite large, as you see in the setup. It could be used even with a lens booster, reaching infinity. But in this case one need to use a short Chinese helicoid which gives a less interesting MFD of circa 2 meters. So, I preferred a longer helicoid and no lens booster. The resulting MFD reaches a much closer 15cm or so.

What is equally interesting, the original setup includes a snap-on cap with a hole and two in-lay disks with holes of different diameter. No deep investigation is needed to catch the original way to close the lens with three snap-on rings. The lens with the cap on is in the center of the snap.

As the lens has no precise inscriptions indicating its focal range and speed, I compared it to others put on the same camera. The focal length turned out to be close to 90mm. And aperture value... circa f3. This surprised me, so I'll check it again. But it does not sound improbable, as the image rendering is definitely less dreamy than we see from the fastest Heligons.

Here come some first samples, Sony Nex.

#1 Wide open

#2 With the cap on, with the largest aperture among the three.

#3 Wide open

#4 With the aperture cap on, taken in a different light.

#5 MFD, artificial light, contrast and exposure boost.

#6 MFD, contrast and exposure tweaks.

#7 Back to sooc, a temporary replacement of portrait.

A couple more of shots edited to taste. This lens is quite atmosphere capable!

#8

#9

iangreenhalgh1 · Expire: 2014-01-07

It looks to be very poorly corrected for spherical abberration in the visible spectrum (hence the strong diffuse glow), so it might be a lens for wavelengths outside the visible.

alex ph · Joined: 16 Mar 2013 Posts: 1674

The person from whom I got the pack told me his father was ophthalmologist and enthusiast photographer. Consumer spectacles depicted on the original box, instead of a kind of industrial XZ673kU037652 legend, reinforce this direction even more. I wonder if the lens was not originally intended for sight or glasses inspection.

iangreenhalgh1 · Expire: 2014-01-07

I know Rodenstock make spectacles, they probably make optical equipment too, so it probably is from such a piece of equipment.

Try using it on subjects that benefit from a soft, diffuse glow - bright lights, flowers, portraits etc.

alex ph · Joined: 16 Mar 2013 Posts: 1674

That's my intention, really curious to see the results.

jamaeolus · Expire: 2015-08-20

looks to be a fun project.

alex ph · Joined: 16 Mar 2013 Posts: 1674

calvin83 · Joined: 12 Apr 2009 Posts: 7584 Location: Hong Kong

Interesting Heligon! Never see any of these!! Like 1

alex ph · Joined: 16 Mar 2013 Posts: 1674

Thank you Calvin!

This is how the lens renders with Sony FF. Surprisingly, it gives less glow than on APS-C, but corners revealed make think of a projection lens.

#1 Sooc jpeg. The background is what you see in #3.

#2 Sooc jpeg

#3 Autocontrast

alex ph · Joined: 16 Mar 2013 Posts: 1674

In the twilight the lens draws in a marvellously cosy way, leaving the whole image breathe. A kind of cinematographic feeling.

#1

#2

#3

#4

#5