How drastically protected are old lenses' designs?

[Juan Valdenebro]

What would happen (legally) if suddenly there's a company producing a lens that's very close in design to a previous lens? Which are the limits about design and distance in time?
Say Zeiss' or Voigtlander's crew decide to produce a 35mm f/1.8 that's basically the same as the 1950's Nikkor-W... Would it be illegal? What about a variation, or the same design with one or two stops less speed? I have never read or heard comments on this... Thanks for sharing opinions!
Cheers,
Juan

 

[aizan]

i vaguely remember something about optical formulas not being copyrightable. it's similar to typeface designs. can anyone confirm?

 

[jschrader]

first, I think patents expire after a time (20 years typically (?) or always (?))

second, you can patent only technical solutions that are new. So, you cannot get a patent on the idea to combining several lenses to fight aberration (that has been done before).
But you might patent (and lenses have been patented) putting a negative lense with a high refrative index in a certain position of a certain combination of lenses - if nobody ever did that in practice, or in a publication

and it must be an invention that has a certain "innovative value". This is decided by the authority granting the patent.

So back to the original question, the old Nikon lens design, if it was ever patent protected, then this patent should be expired

 

[JRminox]

Many lens designs are patented and therefore protected for the duration.
Another real world protection is the glass itself. Lenses depend on glasses with specific index of refraction and other properties that determine their exact shape. Glasses with proprietary formulas are often difficult to duplicate thereby offering a practical protection to the manufacturer. Many lenses exploit similar designs concepts such as Planar or Sonnar, Gauss etc. but the devil is in the details.

 

[ferider]

The Nikkor 35/1.8 was US patented in 1959 (HIdeo Azuma, "High aperture wide-angle objective lens", US Patent 2896506, Filed 1956, Granted 1959).

You can read the patent here, for instance: http://www.google.com/patents/US2896506

It's a good example of a lens patent which protects the basic design (lens diagram, rough relative positions, glass indices curvatures and sizes), and where exact numbers are given only as one embodiment of the invention. The patent protects more than this embodiment.

In the US a patent can have a term of 14 to 20 years, depending on the type of patent and when it was filed. So, AzumaSan's patent expired in the late 70s.

Roland.

 

[jschrader]

Another real world protection is the glass itself. Lenses depend on glasses with specific index of refraction and other properties that determine their exact shape. Glasses with proprietary formulas are often difficult to duplicate thereby offering a practical protection to the manufacturer. Many lenses exploit similar designs concepts such as Planar or Sonnar, Gauss etc. but the devil is in the details.

That is correct. But most (all?) lens producers buy glass from the same few glass producers. To copy a lens, it would require an analysis of all lenses' exact position, curvatures, and glass type. That is probably possible, but if it is cheaper than to calculate the same lens from scratch (with a good guess of the lens to be copied) I cannot say.

But for classical lenses, I believe it is known which glass types they used, so one should be able to redo an old Nikon lens.

 

[charjohncarter]

As you know Juan, I know nothing about the technical aspects of lenses, but I think you raise an interesting point. With everything going digital and computer generated lenses, the final output of our products are very indistinguishable from one lenses/one sensor from another. Maybe, producers will make retro lenses not only as a marketing ploy, but also to add some spice (soul) to our photographs.

 

[Roger Hicks]

Dear Juan,

As others have said, it's normal patent law. But ask yourself this: WHY would any major manufacturer want to copy someone else's old lens? It would be an admission that their own newer lenses weren't as good.

Second, there are plenty of old lenses around, some in excellent condition, generally at reasonable prices, though of course there are exceptions such as Thambars or pre-aspheric 35 Summiluxes. The market for copies would be tiny, and they'd probably cost more than even expensive old lenses like the Summilux and Thambar.

Third, new glasses are introduced, and old ones are dropped, so the original glasses may not be available.

Fourth, while the designs may have fallen out of patent, the names are often trademarked: you can make a Sonnar copy, but you can't (without a license from Zeiss) call it a Sonnar.

Fifth, the current 1,5/50 C-Sonnar provides a good example of a redesign of an old lens, with its faults (focus shift, vignetting) as well as its qualities (very high contrast, a "look" of its own).

Sixth, to quote Dr. Nasse of Zeiss, "No matter how much computer modelling you do, you never know how a lens is going to perform until you build it."

Cheers,

R.

 

[sevo]

If any, we might see re-issues in AF mounts or with some other distinctively modern feature outside the optical block. From a makers point of view, selling old designs in old mounts is hard to justify, as that puts them into full competition with the used market.

 

[DominikDUK]

Except for Zoom lenses and a few other fixed focal length most lenses designs were created before or shortly after the first world war. The most used lens design is the Tessar (1903), the Planar another favourite (1897)and the Plasmat (just after WW1). Modern lens designs are mostly tweaks of already existing designs and not alltogether new designs. In all honesty why should they design new lenses that can't beat the old design. The planar is near perfect ad some asph. elements and you have a new lens that is still 99% double gauss but might have better transmission.

 

[Roger Hicks]

Except for Zoom lenses and a few other fixed focal length most lenses designs were created before or shortly after the first world war. The most used lens design is the Tessar (1903), the Planar another favourite (1897)and the Plasmat (just after WW1). Modern lens designs are mostly tweaks of already existing designs and not alltogether new designs. In all honesty why should they design new lenses that can't beat the old design. The planar is near perfect ad some asph. elements and you have a new lens that is still 99% double gauss but might have better transmission.

Not really, no. I mean, of course you can always trace histories back but the Biogon (early 50s) is definitely a landmark. So are extreme speed lenses such as the 1,5/50 Sonnar (early 30s) or f/0.95 Canon. Or for that matter, 50/1 Noctilux. And catadioptric designs: Oude Delft and more (1940s, I think). And most fisheyes. Or Retrofocus (reverse-tele) designs.

Inevitably, many lenses are improvements and refinements, and there are fewer and fewer basic discoveries to be made, but equally, there is always genuine innovation, and a lot of it has happened since the 1920s.

Cheers,

R.

 

[DominikDUK]

Roger I fully agree with you but the the biggest advancement was not in lens construction itself but in the use of new coatings, floating elements, aspherical elements and new glass types.

Also the point I wanted to make was that old lens designs are still relevant and used as basis for more modern lenses until today (except zooms)

btw the Biogon is again a prewar lens this time WW2 (1935). 🙂

 

[zuiko85]

If the OP is talking about manual focus lenses then prices would be very high to reproduce some of the gems from the past. How much would it cost to reproduce a 50mm f1.4 SMCT Takumar? I would be surprised if it could be sold for less than $1600 if made now. Just basic inflation would drive much of that increase, that and the limited market.

 

[sevo]

How much would it cost to reproduce a 50mm f1.4 SMCT Takumar? I would be surprised if it could be sold for less than $1600 if made now. Just basic inflation would drive much of that increase, that and the limited market.

The limited market is the issue - and maybe the use of now banned radioactive glass. In general, production cost has dropped to almost negligible levels, compared to back then - lenses of that design generation were the bundled kit lenses sold with the last generation of non-AF brand name SLRs, often for less than $200 for camera and lens. And they'd be even cheaper now, if sufficient numbers could still be sold...

 

[Roger Hicks]

Roger I fully agree with you but the the biggest advancement was not in lens construction itself but in the use of new coatings, floating elements, aspherical elements and new glass types.

Also the point I wanted to make was that old lens designs are still relevant and used as basis for more modern lenses until today (except zooms)

btw the Biogon is again a prewar lens this time WW2 (1935). 🙂

I fully take your points, and of course I was thinking of the 21mm Biogon in Contax fit and the 38mm for roll-film, which (I think) were somewhat different from the 1935 version (which I had forgotten). Even so, I'd suggest that coating (incuding multicoating after the early 1940s) allowed different designs with more air-glass surfaces; that "floating" elements were used in some soft focus designs long ago, as far as I recall; and that glasses with low dispersion and high refractive index also made new designs possible. I don't recall, for example, early wide-angles with concave front elements, such as are now quite common.

We are not, I think, disagreeing: the 1890s Cooke Triplet is the basis of countless modern asymmetric lenses, for example. But equally, I think you overstated your case slightly in the earlier post.

Cheers,

R.

 

[tunalegs]

Somebody could make some money reproducing the Meyer Primoplan. The used prices for these lenses have gone sky high. Heck the Trioplan is even simpler and the prices are even higher...

If anybody were to reproduce old lenses they'd have to choose something fairly scarce and fairly popular to have any hope of making money. Kind of like Lomography's petzval lens.

 

[Juan Valdenebro]

Thanks for the great information!
If we keep talking about the example, The Nikkor 35 1.8, we´re talking about a lens that's sharp, small and well corrected for barrel distortion, I read... We have very few options for that... And it's not a cheap lens, that's why I thought a new version could find buyers... Another case: Summarons are sharp and low distortion too, but most of them are hazy, and flare prone too, so those would be great brand new too... Another good point, for street shooters, would be the possibility of those lenses in lower speeds, so they would be as small as possible, distortion free and haze & flare free... Personally I'd love that, because I carry a second camera with faster film and a 1.4 lens for low light, so I have no interest in doing everything with the same big lens when 999 out of 1000 shots I do are done at f/8... Yet I think those new lenses would be sold, but well, it only matters what CEO's think about it...
In my case, I would pay good money for a modern, really small 35 with great field flatness, sharpness and distortion control, say a Zeiss Biogon 35 f/5.6, because that would be the best lens for my whole life, and a very light one to carry, and visually insignificant.
Cheers,
Juan

 

[tunalegs]

In my case, I would pay good money for a modern, really small 35 with great field flatness, sharpness and distortion control, say a Zeiss Biogon 35 f/5.6, because that would be the best lens for my whole life, and a very light one to carry, and visually insignificant.
Cheers,
Juan

MS Optical Perar 3.5/35? It's about as small as they get.

 

[Juan Valdenebro]

MS Optical Perar 3.5/35? It's about as small as they get.

I couldn't find good comparisons of the Perar against a Biogon, talking about field flatness and perspective control when I was interested, but yes, it's as small as we have now... If someone has a link to that comparison, great!
Cheers,
Juan

 

[sevo]

Somebody could make some money reproducing the Meyer Primoplan. The used prices for these lenses have gone sky high.

The current price is determined by rarity. Produce a few hundred and the rarity is gone - and with it, the current price. And at that point you are still a magnitude or two below the level where mass production grows cheap, so you cannot adjust the sales price down to match the drop in demand.