Shift and Tilt-lens: Hartblei 40 mm

[Asher Kelman]

Stefan,

You mention the T* coatings! That is interesting to me.

It's amazing about the differences in coating. I have a new Canon 50mm 1.2 L and amazingly it is very flare resistant, converting the brightest lights as into rich glows of angels. The other lens that surprised me is the Cooke soft portrait lens the f4.5 210 mm PS945. When I opened the impressive metal presentation box, I thought "Great, they have a built in lens shade', only after I tentatively put my finger into the space of the lens shade did I find the lens surface! There are essentially no reflections, that how perfect the lens coating is and this shows what is state of art for hand made lenses.

So when you talk about the T* coating being superior, I'm very much interested since this alone, even without the superior resolution really is helpful. I like being able to shoot not fearing reflections! So how do the T* coatings today with the new lenses differ if at ll from Zeiss lenses made 5 or ten years ago. Has the formula remained constant?

Asher

 

[Stefan Steib]

Zeiss improvements

Asher sorry for the delay, still recovering from new year...........;-)

I frankly don´t know. I think that the coating was pretty good already 10 years ago, but for details I have to ask at Zeiss. I´ll do that as soon as they are back here at work which will be on the 7th.

What I DO KNOW is how much effort we have put into defeating stray light and flare inside the lens to get this down to a minimum. I can also tell you that we are working on additional lens shades to be not in the way at full movements.
There is a recent document of Contax in English I found about the T*coating:
source http://www.contaxcameras.co.uk/digital/tvsdigital/tvsdigitaloverview.asp

Carl Zeiss T* anti-reflection coatings ensure the virtual elimination of unwanted reflections inside the lens. This means that only image-forming light reaches the image plane of the camera. Your photographs will have greater impact due to higher contrast, deeper color saturation, more shadow detail and cleaner, crisper colors.
Each of the seven layers of the T* anti-reflection coating is optimized for a portion of the total bandwidth of white light and together the seven layers cover the entire visible spectrum. The thickness of each coating layer is 1/4 wavelength of the frequency of light that the layer is dedicated to. Light is phase shifted 1/4 wavelength as it passes through the coating the first time. If the photon is reflected, it passes through the anti-reflection coating again and as it passes, it is phase shifted again 1/4 wavelength. Now, the reflected photon is 180 degrees out of phase and it is annihilated.
Carl Zeiss invented anti-reflection coatings and their continued dedication to the elimination of internal reflections is complete. T* optical coating represents the most advanced optical technology available. It is so good you can see the difference. And T* coatings are only available on Carl Zeiss lenses.

More details soon.

Greetings from Munich

Stefan

 

[Asher Kelman]

Thanks Stefan for this marvelous answer. I'm impressed with the ability to take each group of colors and shift them 1/4 wavelength. I wonder whether Cooke uses their own system or something licensed from Zeiss. For that matter, I am intrigued about where Canon gets the coating for hte 50 1.2L which is remarkable good too.

When Canon lenses appear on other digicams, it's easy to see the common technology or when MF backs are specified as using a Kodak or Dalsa back, we know then too. Coatings however, don't seem to be disclosed as I guess it's a black magic that people like to keep very secret.

In fact, when I see Zeiss lenses on Sony cameras, I ask myself, 1."Have they licensed the name, the design or just the coatings?" and then 2. "Who actually makes the "Zeiss" lenses?

I know that there's a lot of potential interest here in using the superior Zeiss optics in getting great wide angle images that are up to the resolving power of the 1DsIII.

Asher

 

[Stefan Steib]

T* Licensing

I don´t know about Sony, but here is a document about Rollei HFT Coatings
source here - http://www.dantestella.com/zeiss/coatings.html
originally from a Zeiss publication of 2001:

How do Zeiss T* and Rollei HFT compare?

Since this has recently grown into a frequently asked question we feel it is appropriate to provide an official and unequivocal answer from Carl Zeiss:

HFT, meaning "High Fidelity Transfer", is a multi-layer anti-reflection coating system co-developed by Zeiss and Rollei. This occurred several decades ago at a time when Zeiss T* coating was new on the market and could only be applied at the Zeiss Oberkochen plant to rather small camera lens production batches. Rollei envisaged very large volume production in their then new Singapore plant and therefore encouraged this joint development.

Today the situation is this: HFT has become a well established trademark for Rollei's proprietary multi-layer anti-reflection coating. The optical performance of this Zeiss/Rollei co-development is so close to the performance of the original Zeiss T* that one can hardly detect any difference in all practical picture taking.

The Planar®, Distagon®, Sonnar® lenses that Rollei produces under license from Carl Zeiss are all HFT coated by Rollei. All the lenses that Carl Zeiss produces for Rollei at the Zeiss Oberkochen plant are actually Zeiss T*. coated. However, the designation on these lenses is "HFT" in the interest of remaining fully consistent throughout the Rollei product range.

Camera Lens News No. 13, Spring 2001

Sony published this http://sonystyle.ca/html/CybershotGlossary/quality_lens.html in 2006
quite informative and instructive with graphics.

I also experienced this with several of my Contax KB lenses (28,35,85,135) that I use on my 5D and all of them show much stronger blue channels , compared to my other brand lenses.

regards

Stefan

 

[Stefan Steib]

Sony - followup

found it here:

http://www.zeiss.com/c12567a8003b58b9/Contents-Frame/c7fb960ed6f52805c125711e004ad17c

"3. Why are ZEISS lenses for Sony cameras produced in Japan?
Sony produces digital cameras of different types in extremely high numbers in several factories in Japan. The lenses for these cameras have to come from lens factories near the Sony camera manufacturing facilities to ensure reliable deliveries and minimize the economic risk of interrupted supplies.

ZEISS lenses for Sony digital cameras are developed by lens designers at the Carl Zeiss plant in Oberkochen, Germany. This includes all required quality assurance measures (test methods, test criteria, test devices, test procedures, lens performance target values, etc.) The lenses are then made in a lens production facility jointly chosen by Sony and Carl Zeiss. Quality assurance specialists from the Carl Zeiss plant in Oberkochen implement the ZEISS quality assurance system in the chosen facility. Many ZEISS optic measuring systems are installed. Carl Zeiss audits the lens production areas on a regular basis.

All these measures ensure that ZEISS lenses in Sony digital cameras meet the expectations demanding users associate with ZEISS lenses."

 

[Asher Kelman]

Hi Stefan,

This is slightly "off topic" but can you tell us whether we can use these modern Zeiss optics on the new Hy6 cameras wqith the Rollei mount? This is important since we are about to be testing the Hy6 and would love to have suitable wide angle lenses!

If there is such a possibility, we'll move the dialogue to its own thread!

Asher

 

[Stefan Steib]

Hartblei 35mm only

Sorry Asher

as we use the additional 30mm of the medium format lenses for our shift and tilt mechanism, these lenses do exclusively work on 35mm SLR cameras. There is the exception of the rule: Sinarcam, Alpha, Sylvestri etc. Cam Bodies which use a 35mm mount for their medium Format backs can use our Hartblei Zeiss lenses too.

Regards
Stefan

 

[Asher Kelman]

Yes, Stefan,

I thought that might be the case, just for now at least. But if the Rollei lens mount takes off, then for sure this would not be too much of a challenge to make non-shift addapter from the original Zeiss lens to the Rollei mount. I mention this because there's going to be a need for wide angle lenses of high quality for the new Sinar and Leaf backs to go along with the Hy6 platform. Seems that there might be a lot of people that would love to have a choice of a first class modern Zeiss Distagon!

Just a fantasy!

Asher

 

[Stefan Steib]

Rollei HY6

Asher

you know that there is an announcement for a 35mm wideangle for the Rollei/Leaf/Sinar ?
I don´t know if this info is available in english, but there is a german brochure
http://www.profifoto.de/images/pf_spezial_67.pdf look at page 9
which tells the lens will be made by Schneider (Schneider AFD 2,8/35 PQS),
unfortunately this is NOT true (I was told by the product manager of Schneider).
I mean maybe they will offer a 35mm, but Schneider denies this to be a lens they build.
Very mysterious.
Actually I wish them luck, I only hope they can keep this HY6 project running.

Greetings from Munich

Stefan

 

[Michael Fontana]

Sorry, I just saw yesterday night the thread going on.

Here are screenshots of a 300%-crop of the blue channel - from the already shown back of the Macplus:

The Canon's 50 mm macro has been reduced in size of 85%, to get approx. the same object size - for better comparison. It's 50 mm vs 40 mm.

Yes, its a bit cleaner on the Hartblei's side; identical raw conversion; the Hartblei is a tiny bit more dense, too. It could be expected, I am using some contaxlenses on the 1 DS-2, too.

I personally find - for my photographic needs - others mileages might vary (tilt-function), the stitching route beeing more interesting:

Stitching 3 x Canon 50 macro results in a 9128 x 4968 pix-file, the flatstitched Hartblei 40 shows 7780 x 2667, all at 300 dpi!

With my stitching set-up, including a panohead, I use 7 different SLR-lenses; - the distagon 28 und 35 and going to test the planar 50 as well - so this is much more versatile to me, than a single flatstitch-lens.

I' ve been using the Schneider PC-28, the Zuiko (OM) 35-shift, and the Zörk-Hassi-combo (50 & 80 mm) for a good while, so I' m familiar with the flatstitches possibilities.

As for the time used - yes, it's a factor in a daily prof. photographer's world - to get the flatstiches vs the setup of the panohead, it was kinda similar. For my needs as architecture photographer, I would need the Acolens-Software, for correction of the Hassi's 40 mm distortion as well; I don't think it will be really that faster than to stitch 3 images together.

For photographers working more in the studio than I do, plus wanting the tiltfunction, the 80 or 120 macro from Hartblei might be a good decision.