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Various Zeiss super-16 lens conversions


mark leuchter

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I've used the Zeiss 10-100 converted to 11-110mm for s-16, and found the optical quality to be superb. I've been informed that the s-16 conversion of the lens to 12-120mm is not done by Zeiss but by Optex. Does anybody have experience with the 12-120 version, and if so, could you offer comparisons to the 11-110 model?

 

Mark

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I've been working with the 3 and I actually don't see why you would do this. Since it covers S 16, I think it's nicer to have wider angle than longer focal length. It's always a problem to have wide shots that are commonly needed, and on the other hand, very easy to find long focal lengths, that are not so often needed...

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I asked a similar question on another forum (Eclair ACL) and I got this answer from Hans Hansson, FSF, Sweden (maker of the A-Cam):

 

"Zeiss has reconstructed the rear elements on the 11-110mm zoom lens. If you shall cover a larger area, super-16, you have to increase the focal length, if not reconstruct the whole lens. If the light coming into the lens shall cover a larger area the intensity will be less according to the optical and physical laws."

 

"Cooke made the same with the Var-Kinetal 9-50mm T2.5 and got a super-16 lens 10.8-52mm T2.8. by changing 4 lens element in the rear unit, as Barry Billington, at Cooke Optics, told me today."

 

"OpTex convert the Cooke 9-50mm T2.5 to a super 16 lens 11-60mm T3.0 by adding an extender to the back of the lens. As soon as you start adding lens element you are loosing quality."

 

I later asked him how much quality do you loose when adding the range extender. He said figure 20 percent.

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Sorry, I read too quickly, I thought you wanted to convert a super 16 11-110 to s 16 12-120. Converting a 10-100 to 11-110 sounds to me more interesting than to 12-120, unless it is said that the quality will be better. Was just talking about the focal range

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Guest stickfigure

I had my 10-100 converted by Optex 5 years ago when I did my camera conversion. Zoom still matched my Ziess SS Primes very nice. The only thing I hated was losing the speed of the lens from a t2 to a t2.4. Shot the Sundance Grand Jury Prize "Primer" with it. Although I will say most of the jobs I shoot with it are commercial going into a Spirit room for xfer, and it all looks good in there.

 

Troy Dick, soc

www.stickfigurefilms.com

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Thanks for the feedback...I will look for your film, Troy, and check out how the Zeiss 12-120 performed.

 

What about the sort-of older Zeiss 10-100 T 3? I know that the oldest ones aren't so terrific, but I've read that the "multicoated" ones are considerably better. How do they compare with the 10-100 mk 2?

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Here are some correspondencesI had with Hans Hansson on the Eclair ACL list. Your question regarding the T3 Zeiss is answered by him toward the bottom of the post:

 

Hi Mike

 

The T* is a trade mark for Zeiss lenses with multi coating, anti reflex

coating. What I now there are no difference in quality between Zeiss zoom

10-100 mm T2 and 11-110 mm T2.2. The later covers super-16.

The OpTex conversion of the 10-100 mm T2 lens to super-16 12-120 mm T2.4

have a 1.2x extender added on the rear lens element. As soon as your adding

extra lens element you start loosing optical quality, but I can´t tell you

how much, let say 20% ?? or less in resolution.

 

Hans Hansson, FSF

Sweden

 

Hi Mike

 

The shortest focal length you can use with the 10-100 mm Zeiss T2 zoom lens

on a super-16 format is around 25 mm on infinity and 40 mm on 5 feet.

With shorter focal length you will get dark corners.

 

The Zeiss 10-100 T3.0 will not cover super-16 at all.

 

The Cooke 9-50 mm T2.5 will cover super-16 from around 20 mm and up.

No diff. between inf. and 5 feet.

 

The Angenieux 9.5-57 mm covers super-16 from 25 mm and up.

No diff. between inf. and 5 feet.

 

Most prime lenses from 12 mm and longer focal length will cover super-16 mm.

 

The Zeiss HS 9,5 mm T1.3 will cover super-16, but is not very sharp outside

the normal-16 mm area. This lens is not listed in the Arri´s list over Zeiss

lenses covering super-16

 

 

The Kinoptik´s 9 mm prime lens covers super-16, and is very sharp even in

the corners, It´s a little bit warmer than the Zeiss lenses, more like the

Cooke lenses.

 

Hope this information will help you

 

Hans Hansson, FSF

Sweden

 

Q: I've noticed a lot of these lenses on Ebay recently. Naturally the T2's

cost more. But why?

 

A: Speed! One and 1/4 stop more light.

The extra price you have to pay for the T2.0 Zeiss zoom comp. to the T3.0

zoom comes from the more complicated construction with more glass and higher

T-stop.

 

 

Q: Is the Zeiss 10-100 T2 a superior lens in terms of image quality as

compared to the 10-100 T3 and T3.3?

 

A: No, the optical quality of the T3.0 version with the red * is excellent.

The T3.3 version is not multicoated and therefore giving a lower contrast.

 

If you look at the Abel Cine Tech guide to Super-16 it says:

 

"Unlike the list of lenses below under Zoom Lenses, which are designed by the manufacturer to cover the Super16 area at the outset, te optical conversions utiliaze a set of optics added to the rear of the lens in the form of a small (0.2X-0.3X) range extender. Because this conversion is, in effect, adding additional optics to an existing lens design, keep in mind that the resulting lens may bear a slight degradation in image quality."

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The Mk 2 has a 87mm front as opposed to the 80mm front on the Mk 1. From what I was told by Hans, the image quality of all of the lenses with the T* is identical. You are simply paying more for the speed with the Mk1 and Mk 2. Also, he said the mark 2 has less vignetting. However, I have not tested this.

 

Also, on a slightly different subject, if you go to www.filmcamerakit.com, they say the 10-100 lens remains as sharp optically after you add the range extender making it 11.5-115. That would contradict what Hans says, but I think there is more logic to his statement. By adding range extenders you are forcing the glass to go through "optical hoops." Read the discussion on cinematography.net about adding the Abekas to video lenses. Mitch Gross makes some very good points.

 

That's why it really amazes me that Visual Products sells the Cooke 10.8-60 (a conversion) for $500.00 more than the 10.4-52 (a lens designed for Super 16).

 

 

How does the image quality of the Zeiss 10-100 T* compare with that of the Zeiss 10-100 T2 Mk 2?  Is the difference primarily one of speed as opposed to sharpness?

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