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ZEISS. Discover the fascinating world of birds, and win a birding trip to Columbia

Interview with Zeiss Senior Optical Scientist (1 Viewer)

Binastro

Well-known member
New phones every 6 months don't make me feel happy.

New cameras every 6 months don't make me feel happy.

New washing up liquid, New soap, New this and that doesn't make me feel happy.
Something like Lux soap of 50 years ago made me feel happy, and would still make me happy if they still made it, as it was.

The whole world is run on New. It makes me feel sad and it pollutes the world.

B.
 

tenex

reality-based
This cosmetic change is necessary because YOU (i.e. the consumers) will get bored of things eventually even if they are perfect. The market demands something "new"...
The whole world is run on New. It makes me feel sad and it pollutes the world.
I'm with Binastro. I also disagree that this is market-driven, a natural difference of human world-view -- rather something in the nature of late capitalism, its evil discovery that advertising can induce most people to buy just about anything, regardless of whether it's actually better or they need it.

P.S. Regarding soap, you might be interested in two American products: Ivory is still AFAIK a classic 19th-century soap, and Dawn while more recent is an unequaled dish liquid, even used to clean oil-soaked birds.
 

eronald

Well-known member
Hi Edmund,

Allow me to answer your first question on behalf of a hypothetical optical designer who works in a hypothetical prestigious sports optics company:

The updates to an existing alpha-class binocular model are not driven by technical reasons. However, "change" is needed for marketing purposes (i.e. to create hype). Every five years or so a "new model" must be introduced based on a marketing concept called "just noticeable difference" to create hype and an illusion of change in the mind of the consumer. This is good for everybody: the company, the optical designer, and the consumer. It keeps the market alive, the company stays in business and the optical designer remains employed.

This cosmetic change is necessary because YOU (i.e. the consumers) will get bored of things eventually even if they are perfect. The market demands something "new" so our companies have to create a "new product" every few years. When the "new product" is introduced, those who buy into the hype will buy the new product and will feel happy. Those who see the superficiality of the new product will feel a renewed appreciation of the older product they have [now called a "classic''] and feel happy. The optical designer keeps his job and will feel happy. The company executives stay in business and will feel happy.

So, the answer to your question "Why did you wish to update your previous product?" is "to make everyone happy".

;)

-Omid
Omid -

You’re so right!

But still with luck the question might shake free a small nugget or two of information.

Also, to be cynical, if journalists asked this question every time and readers expected an answer that makes sense, companies might stop this business of “same old new”.

I do appreciate questions from my own side of the house ;)


Edmund
 

Troubador

Moderator
Staff member
Supporter
Hi Edmund,

Allow me to answer your first question on behalf of a hypothetical optical designer who works in a hypothetical prestigious sports optics company:

The updates to an existing alpha-class binocular model are not driven by technical reasons. However, "change" is needed for marketing purposes (i.e. to create hype). Every five years or so a "new model" must be introduced based on a marketing concept called "just noticeable difference" to create hype and an illusion of change in the mind of the consumer. This is good for everybody: the company, the optical designer, and the consumer. It keeps the market alive, the company stays in business and the optical designer remains employed.

This cosmetic change is necessary because YOU (i.e. the consumers) will get bored of things eventually even if they are perfect. The market demands something "new" so our companies have to create a "new product" every few years. When the "new product" is introduced, those who buy into the hype will buy the new product and will feel happy. Those who see the superficiality of the new product will feel a renewed appreciation of the older product they have [now called a "classic''] and feel happy. The optical designer keeps his job and will feel happy. The company executives stay in business and will feel happy.

So, the answer to your question "Why did you wish to update your previous product?" is "to make everyone happy".

;)

-Omid


Omid, I love this, and it explains why toothpaste and shampoo and almost everything else gets re-packaged every few years with a big NEW marked on the label.

The only aspect missing from your analysis is that when the new bino first reaches the market, not everyone buys it. So when the 'new' 'refreshed' 'updated' and 'improved' version comes out 5 years later, it isn't just to get existing owners to 'upgrade' to it, it is to try to capture some of the potential buyers who didn't fall for it the first time, in other words, it seeks to increase the model's market share.

Lee
 

temmie

Well-known member
A well-ballanced 8X32 SF weighs only 600gr according to official specifications, a Leica 8X32 Ultravid weighs a hefty 535 grams. What if Leica copies this concept by glueing 65 gram extra weight to the eyepiece side of their 8X32 binoculars?

:)

-Omid
While you are in playful mode, I am sure you realize the Zeiss's length contributes to better correction for chromatic aberration, and it's surplus weight is probably due to using ocular design that enables a much wider FOV, compared to the Leica.
 

Troubador

Moderator
Staff member
Supporter
While you are in playful mode, I am sure you realize the Zeiss's length contributes to better correction for chromatic aberration, and it's surplus weight is probably due to using ocular design that enables a much wider FOV, compared to the Leica.

Not to mention making room for your fingers to make a full open hinge grip possible.

Lee
 

Binastro

Well-known member
But the lenses actually bought by consumers can fall woefully short of the reviewed sample, which is likely cherry picked by the makers for review.

I have had numerous examples of lenses that fall short of expectations, and a few that are well above average.

Regards,
B.
 

Omid

Well-known member
United States
Lee and Edmund: You are both welcome.

Binastro: I have not bought a new phone since 2015. I have a Blackberry. I don't use any apps and I am not on any social media.

If you hate to see a new phone introduced every 6 months, then you should look at what is happening in the "fast fashion industry" championed by brands like Zara and H&M. Fast fashion (not fashion as a whole) is a $36,000,000,000 industry per year. Americans are purchasing five times the amount of clothing than they did in 1980, The average American household produces 70 pounds (32 kg) of textile waste every year. I have dress shirts which I have bought more than 10 years ago and I still use, same with ties and made-to-measure suits. (I am lucky I have not gained much weight) I have a pair of crocodile dress shoes which I have bought in 2013 and I still wear often. About two years ago I paid $120 to replace their soles! ;)

-Omid
 
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pbjosh

missing the neotropics
Switzerland
Apologies for the thread drift, but I agree with Omid that the waste of clothing is staggering, and I suspect that the US is indeed among the worst in the world for waste in general. In some aspects of disposable items and quick replacement culture, the entire developed and developing world appears to be following in the US's footsteps, sadly.
 

SeldomPerched

Well-known member
Apologies for the thread drift, but I agree with Omid that the waste of clothing is staggering, and I suspect that the US is indeed among the worst in the world for waste in general. In some aspects of disposable items and quick replacement culture, the entire developed and developing world appears to be following in the US's footsteps, sadly.

Though a great admirer of the USA I will just say I noticed people eating out never seemed to finish their food in restaurants, but this is an observation based on the early 1970s and I was amazed to see portions were much bigger too. (I wasn't complaining!)

Tom (and back to the thread)
 

pm42

Well-known member
Though a great admirer of the USA I will just say I noticed people eating out never seemed to finish their food in restaurants, but this is an observation based on the early 1970s and I was amazed to see portions were much bigger too. (I wasn't complaining!)

I happened to us too when we were working here end of the 90s. Once in a fancy french restaurant, we asked why the portions were so big and the "Maitre d'Hotel" explained that for most of its clientele, being able to finish was kind of being cheated. And they had doggy bags of course.
One learn not to judge, especially cultural differences but having being raised by people who endured some privations during WWII and were exciting at the end because it meant "chocolate more than once a month", it is hard to fell comfortable with some levels of waste.
 

eronald

Well-known member
Ok, let’s get back to topic. I think that if a tech firm doesnt want to reply to the question “what is new about your new product” then they don’t deserve the free exposure they are getting here. Let them buy an ad. These interviews are less informative and probably about as truthful as soviet era Moscow Radio.

The photo industry which also markets optics from time to time provides a lot of information about their design process after each release of “new”. In fact Fuji even pass around mockups of possible products, and prototypes in public in front of video cameras well before release, and strangely enough they are thriving.

Edmund
 
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Troubador

Moderator
Staff member
Supporter
To avoid misunderstandings and to get back on the topic of the interview with Herr Steinich at the head of this thread, this interview was designed to give an insight into the world of an optical designer, nothing more, nothing less.

Lee
 
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b-lilja

Well-known member
Very much enjoyed the interview. Rare to be able to hear directly from the designer/engineer of a product you deeply admire - thanks!
 

joe101

Well-known member
Continuing my series of interviews with people in the optics world, this time I have been lucky that Thomas Steinich of Zeiss has been willing to donate his time and take part.

Troubador: Herr Steinich please tell us your official job title and how long you have been in this job.

Thomas: Senior Scientist, Optical Design, 14 years.

Troubador: Please tell us about your education, qualifications and where you lived as a child.

Thomas: I was born in Stollberg / Erzgebirge in 1980. We moved to Crailsheim (a small town in-between Stuttgart and Nürnberg) in 1989 some months before the fall of the wall. I finished my school-time in Crailsheim and started university in 2000. My first degree is in Applied Physics from the University of Weingarten and I continued to a Master of Science in Optical System Engineering. During that time, I spent one year at the Fraunhofer Institute for Physical Measurement Techniques in Freiburg and half a year at the Swinburne University of Technology in Melbourne. The first contact with ZEISS was during my Master thesis in 2006 which I finished about wave-front analysis at ZEISS Semiconductor Manufacturing Technology.

Troubador: Where did you work before joining ZEISS?

Thomas: In 2006 I started working as an optical designer for Schneider Kreuznach. The main topics were imaging optics for industrial and photographic applications.

Troubador: Schneider is very well-known and highly respected in the photographic world. When did you join ZEISS, and what has been your career within ZEISS,

Thomas: After 5 years with Schneider Kreuznach I moved to ZEISS Consumer Products in 2011. At ZEISS I had the chance to get involved in very advanced design projects like anamorphic lenses for cinematography, zoom lenses and of course visual instruments like binoculars, spotting scopes and others. The diversity of products at our business unit is something that I like a lot. So as an optical designer you have the opportunity to design many different products. In 2019 I was announced Senior Scientist which is part of our in-house expert career.

Troubador: Where do you live now and are you married?

Thomas: Together with my wife I have been living in Heilbronn for 12 years now. We like living in the city centre, although it is pretty far away from my office in Oberkochen.

Troubador: What are your favourite things to do when you are not at work?

Thomas: Working as an optical designer means sitting a lot in front of a computer. So in my free time I try to do a little sports to compensate for that. Playing badminton is one of my favourites, but also hiking. Travelling is also very important for us. As we both like being outside in the nature there are many spots around the world that we already visited…..and still many, many spots left to visit. Iceland, the island of Réunion and Tasmania were some of our all-time favourites.
And last but not least: Supporting the local ice hockey team “Heilbronner Falken” is also great fun!

Troubador: Do you use binoculars for birding or nature observation? Or not at all?

Thomas: Well, to be honest: I am not a ‘high-power’ user of binoculars, like birders. As you can see from my holiday destinations nature observation is my prime application.

Troubador: How has Coronavirus affected the way you have been working?

Thomas: For me the Coronavirus primarily changed the place of working. I worked completely from home over three months and also supported other business units within ZEISS. Working from home works very well for optical designers. And fortunately, ZEISS had all the IT infrastructure ready for online meetings and remote access to all the relevant data. So the transition was relatively smooth and you can still contact all your colleagues whenever necessary. Now we are more back in the office, but I think working from home will stay part of the working week and will probably increase.

Troubador: What are your normal working days and weeks like (don’t forget regular meetings), and do you work on photo and cinematography, as well as sports optics projects?

Thomas: A standard working week for me is a mixture of meetings, concentrated work at the computer and all kinds of optical questions from different people all over ZEISS Consumer Products. Of course, actually doing optical design is the major part of the workload. But communication is not far behind. For example when you design a new product like a binocular, you have to align your ideas with the mechanical designer, all the colleagues in the production line that are going to build your ideas, the product manager, controllers for budget and manufacturing costs, suppliers like glass manufacturers and many more. And this is true for all kinds of products I am working on from sport optics to cinematographic and photographic lenses. Last but not least: The optical designer is the contact person for any technical optical question and topic that other departments need support with.

Troubador: Please tell us a little about the last 2 projects on which you worked (except SF32 which we will discuss later).

Thomas: Two of my highlight projects are the Harpia spotting scope and the Supreme Prime T1.5/18mm lens. My main target for the Harpia project was to get this amazing imaging performance into a real-life product. Many simulations and theoretical analysis of the assembly process were necessary until we finally came up with this stunning resolution regarding this huge entrance pupil. For our new cinema lenses “Supreme Primes” I designed the ultra-wide-angle 18mm lens with the highest aperture of T=1.5. Looks like everyone wants to have high apertures, directors of photography for cinema and birdwatchers! It was great to have the first working prototype of this lens in your hand after starting with the first rough designs months ago.

Troubador: Do you also work on investigations into existing products and how different aspects of the optics can be improved, including T* and P* coatings?

Thomas: During serial production the optical designer is still responsible for any optical improvements or changes that are necessary. Sometimes assembly and alignment processes can be changed due to new technologies. And this also affects tolerances on individual parts, e.g. lenses.
At ZEISS we have our special experts for coating technologies. So T* and P* reviews and updates are within their responsibility and they give feedback to the optical designer.

Troubador: When you are asked to develop optics for a new sports optics product, what kind of information do you receive to guide you? For example does the brief give targets for light transmission, field of view, eye relief, close focus, length, weight and cost? Are the briefs similar for binoculars and spotting scopes?

Thomas: We have a detailed document with all kinds of information that is necessary to start a new process in optical design. It is very important to thoroughly think about what the important features of a new product are and then the optical designer can think about how to achieve these features. Of course, this document starts from magnification and entrance pupil, defines imaging performance and goes down to size and cost constraints. The criteria for imaging performance, like wave-front deviation, are similar for all visual instruments, whereas size, cost and important features differ a lot. For both binoculars and spotting scopes, ergonomics are very important today. Of course optical quality is vital for both products, with the Harpia scope having been a special challenge to combine the wide field of view at low magnifications with extreme sharpness at maximum magnifications far beyond that of binoculars.

Troubador: Is this concept then tested with software, changing glass types and lens profiles until the targets are met in theory? Can you give an example of how this proceeds?

Thomas:
In general optical design is the process of finding a lens (and in the case of a binoculars also a prism) distribution that is able to a) achieve the given specification that come from the markets needs and b) works as a real-life product and not just on paper. At ZEISS we are in the comfortable position to have all commercial optical design software tools available and even have an in-house software that is specialized on the products we have.
When you start a product design you typically do the bottom-up strategy: you need a deep understanding of the individual parts of your system like objective, prism and eyepiece and then you start with the most simple setup you can think of, so for the objective you can start with a single positive lens. After changing the available variables like radius, glass, thickness you increase complexity step by step, e.g. from a single lens to a doublet – split doublet – even more lenses or aspherical shapes. This process is 100% driven by the designer. The software evaluates and helps you to find the best solution in the trade-off between performance/complexity and cost/mechanical constraints.

Troubador: Then do you verify that the targets are met by producing prototypes and testing them?

Thomas: Yes. Within the software you can verify and analyse all optical criteria perfectly. But real-world prototypes are produced with tolerances and go through a certain alignment and assembly process. Virtual prototyping is already pretty advanced, but hardware prototypes are still necessary to guarantee quality.

Troubador: Do you work according to ISO norms for resolution?

Thomas:
In general, yes.

Troubador: Do you work to ZEISS standards for Modulation Transfer Function, Strehl Ratio, and control of distortions, aberrations (e.g. spherical aberration) and colour reproduction?

Thomas: At ZEISS we have measurement equipment for all kinds of performance criteria and individual aberrations. For example, wave-front analysis gives you a deep insight into aberrations like coma, astigmatism and spherical aberration. The big difference to cinematographic lenses is the image evaluation with the eye. You do not have a fixed plane sensor with a certain spatial resolution but a very individual acquisition device like the human eye. A lot of experience is necessary to take this into account.

Troubador: How do you co-operate with Purchasing and Production personnel to meet cost targets?

Thomas: Please see my earlier answer, regular communication is necessary and therefore both are directly involved in the R&D project team for a new product.

Troubador: Please outline the information you were given to begin developing the SF32 optical system and how this led to the concept for the system. How was this concept developed to meet the target specifications, and how difficult was this?

Thomas: Two of the main driving targets for the new SF32 are the enormous FOV and the Ergo Balance concept meaning you have to shift the centre of gravity closer to the user. And of course, everything without sacrificing any optical performance because the product is in the Victory Line. The objective has to be lightweight albeit having this large field angles coming into the binocular. Large field-angles generate large aberrations that need to be corrected very effectively. This is very challenging. From an optical point of view, certain aberrations have to be corrected in specific parts of the complete system. It is impossible to arbitrarily shift the aberration contributions.

Troubador: SF 8x32 not only has a significantly larger FOV than SF 8x42, its eye relief is an increase from 18mm to 19mm. Was this difficult to achieve? Tell us more about this.

Thomas: Yes, both criteria make life more difficult for the optical designer. For the user of the binocular the huge FOV makes orientation much easier and the longer eye relief also helps to feel comfortable even with glasses during observation. But higher refractive powers are necessary within the optical system and therefore aberration contributions increase. You have to find a smart lens configuration to achieve both.

Troubador: Please describe the distortion profile of SF32 starting from the centre of the FOV.

Thomas: Distortion is one of the topics where the difference between designing a lens for cinematographic applications and visual instruments becomes very obvious. For cinema lenses distortion is an aberration that is corrected to almost zero right to the edge of the FOV. But visual perception is conditioned to expect a certain gradient of distortion over FOV. The SF32 is designed to match this gradient very precisely to have a comfortable viewing experience for the user.

Troubador: Why a doublet focuser? Was this simply to move weight a little further away from the objective end of the binocular?

Thomas: The objective is designed to be very lightweight to shift the centre of gravity closer to the user. Making the focussing lens a doublet is a smart choice to achieve stable colour correction.

Troubador: The ‘cage’ housing the focusing doublet seems large and elaborate. Is the circular element nearest the prisms actually an anti-glare baffle, that moves with the focuser, and has this proved more effective than other anti-glare measures? If not, what is the purpose of ‘cage’ and the circular element?

Thomas: Actually, we put a lot of effort into reducing unwanted stray light for the SF32. As mentioned previously the big ray angles cause more stray light. Advanced optical simulations are necessary to find all unwanted ray paths through the system and stop this light e.g. by putting mechanical stops at the right positions. We optimized the complete system optics and mechanics to reduce parasitic light to the minimum.

Troubador: It appears that the extra lenses have reduced the transmission slightly compared with SF42 and that High Transmission glass has only been used for the prisms. Why wasn’t HT glass used for more elements?

Thomas: High transmission optical glass is most effective in thick lenses or long prism-paths. The high transmission is referred to the internal transmission of the glass block. But total transmission is also influenced by coating technology of the glass-air-interfaces. And glass selection for the individual lenses is not only driven by transmission, but also by colour- and aberration correction. So you have to find a good balance between competing demands.

Troubador: We can see from published images that the optical system is very different from SF42, why?

Thomas: Three essential quantities are very different comparing these two products: the entrance pupil, the FOV and the close focusing distance. All three of them influence the development of the optical design a lot. To find the best solution and shift the centre of gravity close to the eye position a new design form had to be developed to exactly fulfil these demands for SF32. There is no global best design. We always try to find a specific and optimal solution for the goals that are important.

Troubador: Finally, it has been suggested that binoculars are only made to be ‘just good enough’. What is your opinion of this and also the star test used by some enthusiasts to discover the presence and extent of the aberrations present?

Thomas: First, resolution on and off-axis is only one criteria when designing binos. For example weight/size and the desired total transmission (not to mention cost….) limit the number of lenses, and therefore the degrees of freedom to use “aberration correctors” significantly. So you have to balance different and often contradictory needs of the user and find the best solution for the user within the given constraints. I would be very happy to design a bino with no aberrations at all …..but this would end up in a horrible size, weight and cost.
And second, the evolution of the human eye is much slower than the e.g. the evolution of CCD sensors. For cine or photography smaller pixels demand for higher optical resolution. The pixel pitch of the human eye has been quite constant over the last centuries…😉. And additionally, the subjective visual perception is very different for different users looking through the same bino.
As for the star test, for me as an optical designer, the comparison between good and bad aberration correction is only possible with objective measurements equipment like interferometer or MTF that produce numbers.

Troubador: Thank you, Thomas, for what has been a fascinating glimpse into the role of an optics engineer.


Lee

Most interesting Lee, you live an interesting life
 

elkcub

Silicon Valley, California
United States
Hi Lee,

I'd like to add my compliments to the pile.

Being oriented to human factors design, I found several statements by Thomas Steinich to be eye opening:
1. Thomas:*At ZEISS we have measurement equipment for all kinds of performance criteria and individual aberrations. For example, wave-front analysis gives you a deep insight into aberrations like coma, astigmatism and spherical aberration. The big difference to cinematographic lenses is the image evaluation with the eye. You do not have a fixed plane sensor with a certain spatial resolution but a very individual acquisition device like the human eye. A lot of experience is necessary to take this into account.
This is pregnant with meaning. At long last there is concrete evidence that designers (at least at Zeiss) are concerned with ~spherical curvature of the retina.

2. Thomas:*Distortion is one of the topics where the difference between designing a lens for cinematographic applications and visual instruments becomes very obvious. For cinema lenses distortion is an aberration that is corrected to almost zero right to the edge of the FOV. But visual perception is conditioned to expect a certain gradient of distortion over FOV. The SF32 is designed to match this gradient very precisely to have a comfortable viewing experience for the user.
What he means is that unaided viewing includes a change in distortion as a function of field angle, i.e., a visual gradient. But his use of the word also indicates to me that he's a student of Gibson's theory of spatial perception. This is consistent with him being a nature observer (like myself) where realistic spatial perception is an important viewing quality. In a more expanded discussion I suspect he might have commented on the value of matching eye and instrument field curvatures with regard to spatial perception.

In several comments he refers to the extensive use of computerized human eye models to reach final design decisions — clearly revealing Zeiss' orientation to man-machine optimization rather than simply stand-alone instrument optimization. As I suspected there's a lot more going on in the design labs than what appears in sales brochures.

Anyway, he's quite an impressive technical guy and many thanks for doing this interview with him. I learned a lot. Good work! :t:

Ed
 
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Troubador

Moderator
Staff member
Supporter
Thanks Ed and I feel that I should repeat post 15 here to thank Petra at Zeiss for her work in facilitating the interview as well as Herr Steinich for fitting it in while working on demanding projects.

Lee
 

tenex

reality-based
...spherical curvature of the retina... What be means is that unaided viewing includes a change in distortion as a function of field angle, i.e., a visual gradient...
Thanks Ed. That underlined sentence was quite opaque to me, as I remarked previously.
 
ZEISS. Discover the fascinating world of birds, and win a birding trip to Columbia
ZEISS. Discover the fascinating world of birds, and win a birding trip to Colombia
ZEISS. Discover the fascinating world of birds, and win a birding trip to Colombia

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