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View Full Version : Rodenstock XR-Heligon 75 mm f/1.1 - adaptable for super-macro on LF?



dh003i
23-Jan-2009, 21:09
Looking at the image circle from the Rodenstock TV Heligon 75/1.1, it seems to produce an enormous image circle when focused on images very close to the lens. It seems to produce at least a 5 inch image when focused on something half a foot from the lens (this requires the piece white paper behind it being 3/4th of a foot behind the rear element).

The only problem is, it would need a custom lens-board mounting and custom heavy duty retainer ring, as it is a heavy lens, and has a threaded section around the outside of it (of about 2.7 inches in diameter).

Thoughts?

PS: I think it would need a hole bigger than a copal #3 hole!

AutumnJazz
23-Jan-2009, 21:29
75mm? f/1.1? And it covers large format?

What kind of a lens is this?

IanG
24-Jan-2009, 01:28
It's certainly not designed for LF. Any lens used when for close up/macro work will cover a far larger field than it's focussed at infinity.

I have a Dalmey 80mm f1.9 it just covers 35mm at infinity but used as designed for 1:1 copying of CRT's it nearly covers 5x4.

Ian

Peter K
24-Jan-2009, 02:46
It's a lens to project the image made by an image intensifier on a tv camera tube. Without this it's only a big paper-weight.

Dan Fromm
24-Jan-2009, 05:23
In his book The Photographic Lens (1968, Focal Press, London, New York. Originally published as Das Photo Objektiv, 1956, Friedr. Vieweg & Sohn Verlag, Braunschweig), Hans Martin Brandt explains that lenses such as Rodenstock's XR Heligons and TV Heligons were used in pairs for "presentation of the image formed on an X-ray amplifier tube screen to a larger audience via a television system. Conventional optical systems cannot satisfactorily project these images onto the photo cathode of a television picture tube and special optical designs are required for this purpose. …

While it would go beyond our scope to go into this specific application in exhaustive detail, the optical transmission of an anode image to a television system requires so-called tandem lenses. These are a combination of two lenses optimally corrected for infinity. They are arranged in such a way that the anode image is in the focal plane of the first lens, while the photo cathode tube of the television camera tube is in the focal plane of the second lens. …

In the first place this relay optical system must have the largest possible aperture. On the other hand geometric image corrections must be brought to an optimum …

Rodenstock suggest a number of their lenses as suitable for such tandem combinations. Recommended systems for the lens facing the X-ray image tube are the 100 mm Kinemar f/1.5, the 75 mm XR Heligon f/1.1 or the 50 mm XR Heligon f/0.75. The second lens for projection onto the final image plane can be a 32 mm Heligon f/1.3 (for 16 mm narrow gauge cine), the 70 mm Heligon f/1.4 (for standard 35 mm cine cameras) or the 50 mm TV Heligon f/0.75 for Vidicon cameras."

In other words, neither an XR- nor a TV-Heligon is suitable for use as a macro lens.

Also, dh, there's something wrong with your experiment. These lenses have very short back focus.

Peter, the lenses I've seen in this class would also have made good doorstops.

IanG
24-Jan-2009, 06:04
Peter, the lenses I've seen in this class would also have made good doorstops.

Excellent loupes that's exactly what I've been using my Dalmeyer as for about 30 years, also excellent for assesing negatives :D

Ian

Peter K
24-Jan-2009, 10:49
In his book The Photographic Lens (1968, Focal Press, London, New York. Originally published as Das Photo Objektiv, 1956, Friedr. Vieweg & Sohn Verlag, Braunschweig), Hans Martin Brandt explains that lenses such as Rodenstock's XR Heligons and TV Heligons were used in pairs for "presentation of the image formed on an X-ray amplifier tube screen to a larger audience via a television system. Conventional optical systems cannot satisfactorily project these images onto the photo cathode of a television picture tube and special optical designs are required for this purpose.
Dan, in the original book Brandt hasn't mentioned this kind of lenses. So I have to look for the english edition. But this lenses where only made for a short time, when image-intensifier TV chains where introduced. Later one used fiber plates to transmit the image on the TV tube.

BTW, such lenses where used for macro "work" as one can see here (http://www.pbase.com/regit/heligon). Of course one can use a bottom of a bottle too. :D

Peter K

Chauncey Walden
24-Jan-2009, 12:00
I had to go dig the ones I have out of the cabinet to have another look at their possibilities. There was a Kowa 55mm f/1.1, a Kowa 77mm f/1.1, and a Rodenstock 68mm XR-Heligon. Used as designed, they throw a very small image immediately behind the rear element which would be generally useless for anything other than their original purpose except maybe as a digital lens. A little pocket digital camera hanging off the back of one of these beasts would be impressive. The mention of macro made me wonder what they would do reversed. The XR-Heligon worked nicely reversed, throwing about a 3 inch wide image in focus about 5 inches behind the lens and with an angle of view of about 80 degrees - so maybe like a 68mm lens would look on a medium format camera. The Kowas focused only about 1 inch behind the reversed lens so width of the image was basically limited to the width of the front element and the angle of view wasn't quite as wide. There is definitely some weird optics stuff going on inside these. Of course, reversed, you no longer have a superfast lens as the rear (now front) element is much smaller. I might throw the reversed XR-Heligon in a board and see what it looks like on film sometime.

Dan Fromm
24-Jan-2009, 16:42
Peter, we both know that subject to a few limitations (mechanical, coverage) most lenses can be used for most purposes. This doesn't mean that most lenses perform well in most applications.

Thanks for directing us to macro shots taken with some of them. I appreciate that tastes differ, but I'd be ashamed to show such soft images to strangers.

Thanks also for the news that the English version of Brandt's book is updated.

Go here http://www.naturfotograf.com/index2.html to see what Bjørn Rørslett has to say about his 50/0.75 TV-Heligon.

dh, these and similar lenses turn up fairly often on eBay; they're usually offered by scrap dealers who extract them from junked x-ray machines. That they sell for low prices should tell you that no one values them highly. And that should tell you that they're essentially useless.

erie patsellis
24-Jan-2009, 18:49
Yup, just like those old projector and Petzval design lenses were, up until a few years ago.

The soft focus look can have some redeeming value, and for some subjects can (subjectively) be quite nice.

Dan Fromm
25-Jan-2009, 03:04
Erie, as I said, tastes differ.

dh003i
25-Jan-2009, 07:12
Yup, just like those old projector and Petzval design lenses were, up until a few years ago.

The soft focus look can have some redeeming value, and for some subjects can (subjectively) be quite nice.

I tend to like those macro shots, at least some of them, with very narrow dof. Although I realize that many do not. I have some very similar shots of some kind of flower in front of someone's mailbox...one with narrow DOF and the back-ground completely blurred, but half of the flower's stamen's in focus, half out of; and another with the entire flower in focus, but the back-ground also sharp. My friends said that while they liked the "artistic" effect of the narrow dof shot, they would sooner buy the other one -- and this is with a driveway in the background!

In any event, i've re-done my tests with this lens, and they're the same. For objects close to the lens (less than 1 ft), I need to move a sheet of white paper back about 8 inches to get them in focus, and it produces a large image circle.

For objects several feet away, I need to have the piece of paper almost right on top of the rear element, and it produces an image circle about the size of a dime.

Dan Fromm
25-Jan-2009, 12:06
Very interesting. I wonder where the lens' nodes must be to give the behavior you describe. 12" in front of the lens probably (great stress probably) puts the subject around 4f in front of the front node. 8" behind the lens probably puts the subject around 3f behind the rear node. This seems really odd, especially since y'r infinity experiment places the rear node a couple of inches forward from the lens' rear surface.

Would you please do the 'focus on infinity' experiment again with the lens reversed and tell us how far the image plane is from the front of the lens when in focus?

Thanks,

Dan

Chauncey Walden
25-Jan-2009, 14:14
Whoa! That is weird. I tried it with my 68mm like dh is doing and until you get to a 6 inch or so subject distance from the front of the lens, the plane of focus is about a half inch behind the lens. Then, as you move closer, things begin to happen. I used the markings on the end of a light bulb as the target with the lens and a white cardboard box sitting on a rule to judge distances. At about 4 inch subject to lens front, the plane of focus was now about 20 inches behind the rear of the lens and the image of the markings on the light bulb was now 4 inches across. This is, what, 6 to 8x? Definitely have to put the lens in a board and get it on a camera to play with. It will be tricky as slight changes in the lens to subject distance make drastic changes in the lens to film distance. Read - DOF is ultra minimal!