Cinematography Mailing List - CML
    advanced

35mm Still Format Lenses For 65mm

 

Although I've never done it, I recall that a 16mm format zoom can be used on a 35mm camera by mounting the zoom to a tele-extender. Presumably this creates an image circle that covers the 35mm frame. Wasn't this one of Haskell Wexler's tricks back in the day for a lightweight 35mm Cameflex handheld camera rig? I think he used a 2x extender, thus making a 12-120 Angenieux an effective 24-240. That's my somewhat hazy recollection.

In principle, would the same thing work with still photo format (36 x 24mm) fixed focal length lenses to step them up for use on 65mm (52.5 x 23.0mm)? I'm not concerned about the reduction of speed so much as simply covering the 65mm image circle without vignetting or too much fall-off, and maintaining a reasonable resolution. I know the ultimate quality would be subject to a variety of specifics pertaining to the extender and the taking lenses, etc. I'm just trying to determine if the concept may work. And I am well aware that in this industry there is not much that is new, only that which has been forgotten. But there's always somebody that remembers.

And yes, I am aware that most 65mm cameras use converted or remounted Zeiss Hasselblad or other medium format still camera lenses. I'm looking for another solution.

Any thoughts? Any experiences? Pitfalls? Or is the idea just dubious science?

Thanks in advance for any input.

Greg Lowry
Scopica Inc. / Scopica3D
Vancouver


>>And yes, I am aware that most 65mm cameras use converted or >>remounted Zeiss Hasselblad or other medium format still camera >>lenses. I'm looking for another solution.

Are you looking for just a physically small lens? Is a fast maximum aperture important or not?

BTW, did anyone catch that very interesting survey article in SciAm on negative RI lenses? Using diffraction-grating-like objects to do so, with resolution greater than wavelength. Very interesting. There's actually quite a lot going on in the field above and beyond what was mentioned in the article, but it was a good read nonetheless. (if I mentioned it before, please excuse me)

Tim Sassoon
SFD vfx & creative post
Santa Monica, CA

ABSTRACT:

"FEATURE ARTICLES
July 2006 issue

PHYSICS AND OPTICS
The Quest for the Superlens
Built from "metamaterials" with bizarre, controversial optical properties, a superlens could produce images that include details finer than the wavelength of light that is used
By John B. Pendry and David R. Smith


Any thoughts? Any experiences? Pitfalls? Or is the idea just dubious science?

Years ago we've done such a project for Imax at Century Optics. I believe they still use the 150-600 turned 300-1200 lens.

Jacek Zakowicz

Lens tech, Los Angeles


>Are you looking for just a physically small lens? Is a fast maximum >aperture important or not?

Speed isn't the first consideration. I'm primarily looking for physically smaller and lighter weight lens solutions. The Zeiss ZF lenses come to mind, although there are only two focal lengths available at the moment with more coming by Photokina time I believe.

They're T1.4, but slower Nikon or Canon glass would be ok. Even if we lost 2 stops, the ZF’s will still be faster than most Hasselblad conversions. What I'm exploring is the basic feasibility of having a custom extender or step-up optic made to cover the 65mm image circle onto which would be mounted the interchangeable still camera lenses.

I would think that telephotos would be not too difficult. Wide angles probably more (maybe much more) difficult.

Greg Lowry
Scopica Inc. / Scopica3D
Vancouver


Actually, Haskell Wexler wrote an article in the ASC mag that Ron Dexter suggested this to him. The 2x extender increases the coverage by 2x. BTW, I worked with Ron when he was 1/2 block from Haskell Wexler's studio/office in the /70's. 2x's are 2x's and increase any issue a lens has, as we all know.

Hope this helps.

Mark Woods
Director of Photography
www.markwoods.com
Pasadena, California


It WOULD work, if you could get a 65mm tele-extender. I am not sure such a thing exists. Plus, of course, you lose sharpness through all that extra glass.

If I were looking for cheap, sharp lenses for 65mm, I'd look into adapting Hasselblad lenses. I'd also look at the lenses for the Soviet Hasselblad clones.

Okay, they might not be CHEAP, but they are sharp, low flare, and probably less expensive than comparable cine lenses by a long shot.

Scott Dorsey
Kludge Audio
Williamsburg, VA.


>>I believe. They're T1.4, but slower Nikon or Canon glass would be ok. >>Even if we lost 2 stops, the ZFs will still be faster than most >>Hasselblad conversions.

There are some smaller medium format lenses which might be a better idea. Contax/Zeiss 645 for instance. They had an 80mm f/2.0. Some of the older Bronica Nikkors were small. Rollei Zeiss. Mamiya. Even for Hasselblad many of the lenses were bulked up by the Synchro Compur. Stripped down and rebarrelled could be pretty small. Then if you wanna get really stupid, there's older glass from the folding roll films that'll cover just about anything. I'm particularly fond of the Voigtlander f/3.5 Heliar (the Apo Lanthar is a stop darker) from the Bessa II. Before that's totally dissed, Marty Mueller's new Stereo Vistavision camera is using Cosina Voigtlander glass (remounted from M mount), I believe. The first one is supposed to be working in Africa right now...

Tim Sassoon
SFD vfx & creative post
Santa Monica, CA


The key thing is mirror shutter clearance. A 65mm camera needs more, especially with a side mounted shutter (like the ARRI 2C or Panaflex).

If I was shooting 65mm I’d want the sharpest damned lenses I could find. If you’re going to spend that kind of money you want WOW results, not just OK results.

The cost to engineer new housing for lenses is huge. This is the reason it’s so rarely done.

Jorge Diaz-Amador
Designer / Technician
CinemaTechnic, Inc.
Miami, FL USA
http://www.cinematechnic.com


Jorge Diaz-Amador wrote :

> If I was shooting 65mm I’d want the sharpest damned lenses I could >find. If you’re going to spend that kind of money you want WOW results, >not just OK results.

Thanks, Jorge. I'm very aware of the issues you describe. And I agree with everything you write. I'm not new to 65mm origination. But my requirements are different. I'm willing to experiment to see how close to WOW I can get with a somewhat non-traditional approach.

Lenses are just one issue. Perhaps WOW is more attainable than one might suppose. Or maybe not. I'm going to find out. I'll keep you apprised.

Greg Lowry
Scopica Inc. / Scopica3D
Vancouver


Are those the Cosina designed lenses or the Zeiss-Ikon M lenses made by Cosina?

Deanan DaSilva
Dalsa, LA


Haskell Wexler may never have done it, but Stanley Kubrick stuck an extender on an Angenieux 12-240 for the extreme zoom-out from Malcolm MacDowell's face to the entire Milk Bar in "A Clockwork Orange." At the time the little Ang. was the only lens with the 20x range for the shot he wanted. He also did not use a 2x extender but instead a 1.6x, as he did the math and realized that this was all the magnification required to cover his 1.66 frame.

Mitch Gross
NYC DP/TD
Abel Cine Tech


> He also did not use a 2x extender but instead a 1.6x, as he did the >math and realized that this was all the magnification required to cover >his 1.66 frame.

And of course Angenieux made a 1.6x extender for the 25-250 (have one on my desk somewhere, it's tiny).

Jeff Kreines


>Actually, Haskell Wexler wrote an article in the ASC mag that Ron >Dexter suggested this to him. The 2x extender increases the coverage >by 2x.

---Panavision has a 65-390mm Super Panavision zoom. Look at a picture of it and you see a Nikon 50-300mm zoom. So there's a 1.3x extender or modification involved.

A 1.4x extender ought to be practical. Perhaps modifying the rear end mount to the 65mm camera's.

Incidentally, one of the accessories for the Russian OPF18 20-120mm zoom is a 2.1x rear extender to modify it for 70mm.

Leo Vale



Copyright © CML. All rights reserved.