History of (photographic) lenses?

[csant]

Hi,

I have been trying to get an overview on the history of (photographic) lenses - evolution of designs, chronology, revolutionary discoveries… in short, I am trying to learn something about history of lens design. There seem to be a few resources both on the 'net and in the libraries - but before I start wasting time on reading through all of them… would anybody be able to reccomend where to start? Or where which ones are particularly worth reading?

I *think* I am particularly interested in the early history of the photographic lens, and in large format… Or maybe that's just because I love "quaint" and antique stuff…

Thanks in advance!

[Bruce Watson]

THE book, is Kingslake's A History of the Photographic Lens. That's probably all you need. Kingslake is a legend in lens design and for many years ran the operation at Kodak that made lenses.

[Peter K]

As mentioned by Bruce Kingslake's book is a "must". All other important books about history of lenses Kingslake has noted in the references of his book.

[Mark Sawyer]

I have Kingslake's "A History of the Photographic Lens" and "Lenses in Photography", and would recommend both. But if you're interested in pictorial lenses, Kingslake gives very little information on them, perhaps a page (if that) in either book.

For soft focus lenses, Dr. Russ Young's excellent dissertation can be found here:

https://research-repository.st-andrews.ac.uk/handle/10023/505

But of course, whether you're using sharp modern optics or vintage soft lenses, what you learn from books won't be in the same ballpark with what you learn from making photographs...

[Merg Ross]

I would suggest that you look for a copy of, "Photography/ Its Principles and Practice" by C.B. Neblette (550 pages). I have the second edition, printed in 1930, and it would be my choice as a modern day text for teaching non-digital large format photography.The chapters on photographic optics and the photographic objective are excellent.

Much of what I know about the photographic process was garnered from reading C.B. Neblette. I believe he did a later book devoted to lenses, although I have not seen it.

[CCHarrison]

here is a preview of Kingslake book....It is one of the better ones for a general overview

http://books.google.com/books?id=OJrJrEJ-r9QC&pg=PP1&dq=kingslake+lens#PPP7,M1

Dan

[Struan Gray]

If you have a library subscription to IOP journals, this article is worth a read:

http://www.iop.org/EJ/abstract/0959-5309/47/3/314

I*m not sure it's worth the single article price though...

[Dan Fromm]

Arthur Cox' book Photographic Optics

A Lens Collector's Vade Mecum, available on CD from the individual who posts here as CCHarrison. Incoherent in places, incomplete, inconsistent, sometimes incorrect, often infuriating, but invaluable. There's nothing like it for help in deciding which lenses to buy or not to buy.

Kingslake's History is a bit idiosyncratic, slights Kingslakes' contemporaries (perhaps he didn't get on with his classmates?), and says little about most post-WWII developments. We all revere Kingslake for the good work he did as a department head at EKCo but I think there are better sources.

About revolutionary discoveries. There haven't been many.

[CCHarrison]

The Lens Vade Mecum is available for instant download here:

http://www.antiquecameras.net/lensvademecum.html

The VM is more of an encyclopedia of lenses than a history of lenses, per se. But as Mr. Fromm stated - it is a must have and covers lenses from Petzvals to the 2002 voigtlander/Cosina lenses...

Dan

[John Kasaian]

I can recommend both Kingslake and Neblette. Both are long out of print so you best bet might be ABE books.

[csant]

Thank you very much everybody for suggestions. Kingslake looks like a very good resources - I guess I was looking for something along that line… Mark, Dr. Russ Young's dissertation is a fabulous reading - thanks for the link!

[russyoung]

Thanks for the kind words about my dissertation...

I found Kingslake to be unreliable when it came to soft focus lenses, which makes me leery of the remainder.

C. B. Neblette - yes, indeed, he is readable, thorough and for soft focus lenses, an excellent source, esp. the first edition.

There is Paul N. Hasluck's THE BOOK OF PHOTOGRAPHY about 1903... and several numbers of THE PHOTO-MINIATURE as well which are worth reading. If you want [I]early[I] lenses, then Monckhoven is your man, A POPULAR TREATISE ON PHOTOGRAPHY, English edition translated by Thornewaite, 1863.

(Dr.) Russ Young

[Mark Sawyer]

I found Kingslake to be unreliable when it came to soft focus lenses, which makes me leery of the remainder.


I felt like he never really addressed them other than a few dismissive remarks, which is frustrating for those of us who really appreciate them. There's reletively little difference between images from a plasmat, a dagor, a tessar, and a dialyte, when compared to the differences between images from a Verito, an Imagon, a Plasticca, and a Pinkham & Smith...

[csant]

(Dr.) Russ ;)
nice to see you on the forum, too - it shouldn't surprise me that much, should it :) It's a pity that so many illustrations are missing from the digital edition. Is there a chance to get hold of a printed copy?

Mark, I totally agree - once it's needlesharp, it can just be yet-a-bit-needle-sharper, but the big differences are in the softer lenses. As was widely discussed in another thread, it gets "scientific" when it comes down to sharpness, but anything else very much comes down to non-quantifiable matters of "taste" and "beauty" (or lack thereof). Personally, I always have found that to be the more interesting field to explore - and I am slowly discovering that part of the lens universe…

And at some point I'll even manage to get hold of a lens to start exploring it! Because, as somebody rightly pointed out, that's the final goal.

/c :)

[Emmanuel BIGLER]

I have Kingslake's " History of the Photographic Lens"

ISBN-10: 0124086403 Academic Press 1989

and (unlike Dan ;) ) I like it very much. At the end of the book there is a section with short biographies of famous lens designers that I haven't seen anywhere else.
I got the fairly recent reprint of Kingslake's "History" as referenced above, it is probably not yet out of print.

I also have another book, of general interest, by Kingslake :
"Optics in Photography" ISBN-10: 0819407631 reprinted by the SPIE in 2002
.. but the "History" is probably more interesting to those using view cameras including vintage equipment.

There is another book, more technical, by Kingslake, on lens design
"Lens Design Fundamentals" ISBN-10: 0124086500 Academic Press 1978
..I bought it as well, but IMHO it only has an interest for historians of optical engineering who wish to understand how "they" did the job in the good old days without any computer !

For those who want to go inside the details of lens design, I can recommend
1/ to visit Eric Beltrando's web page ; even if you do not read French you'll have access to dozens of vintage lens patents and their technical analysis.
http://dioptrique.info
http://dioptrique.info/sommaire/sommaire.htm

2/ to read (in English) a modern lens design book like:
Warren J. Smith : "Modern Lens Design" ISBN-10: 0071438300 McGraw-Hill 2nd Revised edition 2004
This is definitely a textbook for engineers but there are many historical patents listed and analyzed. Even without going into the details of the numerical calculations, the book offers a superb panorama of our favourite Large format photographic lenses and actually puts them in an interesting historical and technical perspective, including the Petval-type lenses !
The book shows the results of computations with the Oslo(TM) professional sofware for which a free version with reduced capabilities is available, Oslo-EDU; hence allowing anybody having access to a personal computer (including : a linux machine for me) to re-design all classicals lenses up to 4 elements like the beloved tessars and apo-ronars ! And the petzvals ! ;)

[russyoung]

Csant-

Thank you. Alas, because of copyright issues, it is not possible to reproduce ALL of the illustrations from the dissertation; they could be used therein because of a specific exemption for such applications. There are two marvelous examples of rather unpleasant bokeh in the text (one by Stieglitz and the other from the mid-1950s) which would end some debates about the question...

While a debate on bokeh rages on another portion of this board, I cannot agree more that the indefinable qualities of lenses are as important as those which can be easily calculated and measured. I'll just venture that IMHO, the smoothness of tonal transitions should be considered one of the prime criteria in choosing a lens. No need for anyone to get their knickers in a gather - that's just my opinion after reading/skimming over 120,000 pages of books & journals for the dissertation research; it had never even entered my mind before reading extensively and doing a little experimentation to satisfy my own curiosity. While the f/64 school method of bringing the entire image area into acceptable focus removes the concept of bokeh (rendering of out of focus areas), the niceties of tonal change are relevant to virtually all lens-formed images (and pinholes as well).

The civil discourse of this thread is much appreciated.

cheers,
Russ

[Arne Croell]

I have Kingslake's " History of the Photographic Lens"

ISBN-10: 0124086403 Academic Press 1989

and (unlike Dan ;) ) I like it very much. At the end of the book there is a section with short biographies of famous lens designers that I haven't seen anywhere else.
I got the fairly recent reprint of Kingslake's "History" as referenced above, it is probably not yet out of print.

I also have another book, of general interest, by Kingslake :
"Optics in Photography" ISBN-10: 0819407631 reprinted by the SPIE in 2002
.. but the "History" is probably more interesting to those using view cameras including vintage equipment.

There is another book, more technical, by Kingslake, on lens design
"Lens Design Fundamentals" ISBN-10: 0124086500 Academic Press 1978
..I bought it as well, but IMHO it only has an interest for historians of optical engineering who wish to understand how "they" did the job in the good old days without any computer !

For those who want to go inside the details of lens design, I can recommend
1/ to visit Eric Beltrando's web page ; even if you do not read French you'll have access to dozens of vintage lens patents and their technical analysis.
http://dioptrique.info
http://dioptrique.info/sommaire/sommaire.htm

2/ to read (in English) a modern lens design book like:
Warren J. Smith : "Modern Lens Design" ISBN-10: 0071438300 McGraw-Hill 2nd Revised edition 2004
This is definitely a textbook for engineers but there are many historical patents listed and analyzed. Even without going into the details of the numerical calculations, the book offers a superb panorama of our favourite Large format photographic lenses and actually puts them in an interesting historical and technical perspective, including the Petval-type lenses !
The book shows the results of computations with the Oslo(TM) professional sofware for which a free version with reduced capabilities is available, Oslo-EDU; hence allowing anybody having access to a personal computer (including : a linux machine for me) to re-design all classicals lenses up to 4 elements like the beloved tessars and apo-ronars ! And the petzvals ! ;)

I also think that Kingslake's book is actually quite good; I don't think any other book (in English) gives an overview from this kind of historic perspective, other books are usually more user oriented. I also like that he has all the patent numbers in there, so its easy to find them for playing around in Oslo edu. My main complaint with his book are some omissions - one example is that he left out A.W. Tronnier, I would have thought that the inventor of the Angulon, Xenon, Apo-Lanthar, Color-Skopar, Ultron, Telomar, Ultragon and many other lenses should have been mentioned.
I second that the Warren J. Smith book and Oslo edu are de rigueur for the serious lens nut, but having an engineering or science background helps. As an example, here is the MTF for the Voigtländer 360mm Telomar that I did with Oslo Edu based on the patent description (the curve sets are for 5, 10, and 20lp/mm. 100% object height is 16.5° or 106.5mm (33°coverage/213mm image circle)):

[Dan Fromm]

Arne, he also left out G. H. Cook.

[Arne Croell]

For those that are able to read German, here are 2 more (older) choices:

1. Hans Harting: Photographische Optik. 4th Ed., Akademische Verlagsgesellschaft Leipzig, 1952.
Yes, that Hans Harting, the inventor of the Heliar and Dynar! This was the last edition, published posthumously (he died in 1951). Due to the publication date, some modern designs are missing, such as the Biogon-type wide angles, but it is a nice mixture of introductory text with some mathematical calculations in the appendix and some history - for obvious reasons mostly based on German designs.

2. Johannes Flügge: Das photographische Objektiv. Springer, Wien 1955; it was reprinted by Lindemanns Verlag, Stuttgart, in 2004.

[GPS]

Csant-

...
While a debate on bokeh rages on another portion of this board, I cannot agree more that the indefinable qualities of lenses are as important as those which can be easily calculated and measured. I'll just venture that IMHO, the smoothness of tonal transitions should be considered one of the prime criteria in choosing a lens. No need for anyone to get their knickers in a gather - that's just my opinion after reading/skimming over 120,000 pages of books & journals for the dissertation research; it had never even entered my mind before reading extensively and doing a little experimentation to satisfy my own curiosity. While the f/64 school method of bringing the entire image area into acceptable focus removes the concept of bokeh (rendering of out of focus areas), the niceties of tonal change are relevant to virtually all lens-formed images (and pinholes as well).

The civil discourse of this thread is much appreciated.

cheers,
Russ

Everyone has a right to his own opinions, no doubt about it.
Reading that "the indefinable" qualities of lenses are as important as those which can be easily calculated and measured", curious questions come to my mind -really? Important to whom? To you? To all generally? To the optical designers? To all of them? To some of them? If that saying aims to claim (as it seems to do) general validity how come that optical design books don't mention this importance on the same level as those "easily" calculable properties (not that the rest of the optical design would be really so "easy" to calculate...;) ) ?
In fact, you yourself seem to deny this same level of importance. "It had never even entered my mind before reading extensively" - (those 120,000 pages?) - why not, when it is so general and as important as the other optical qualities?? Is this importance so well hidden? Why? Did optical design books overlook this important fact while speaking about all the other important calculable qualities? The chapter -Calculating nice bokeh" is mysteriously missing? Why? Is not missing? Where is it?

Were they really so generally important how come the f/64 school didn't care then?
Or is it just important to some, to you but not to the older (we're not speaking 35mm modern Nikons here...:) ) lens designers?
"The smoothness of the tonal transitions should be considered one of the prime criteria in choosing a lens" - you say. Nothing against your own criteria, of course, you have the right to choose them as they please you. But do you have the impression that such "smoothness" is one of the prime criteria for the majority of photographers in the history of photography? Or, even more importantly, for the optical designers of lenses?

Nobody denies the fact that bokeh is a side effect of all optical designs but I have never found a mention of an (older) LF lens design that would be primarily undertaken for bokeh qualities (knowing that bokeh in your mind too is more than just the residual spherical aberrations of the OOF parts of picture). The same cannot be said about MTF qualities of LF lenses. Therefore I wonder...
Appreciating the civil discourse of this thread too :)

[Mark Sawyer]

Nobody denies the fact that bokeh is a side effect of all optical designs but I have never found a mention of an (older) LF lens design that would be primarily undertaken for bokeh qualities (knowing that bokeh in your mind too is more than just the residual spherical aberrations of the OOF parts of picture). The same cannot be said about MTF qualities of LF lenses. Therefore I wonder...


And all the books on genetic engineering say nothing about the shape of a young woman's leg seen as she turns to walk away. But I suspect even the genetic engineers notice it once in a while...

[Lynn Jones]

I think the latest version of Dr. Kinslake's History of Photography is still in print through academic press. I stil have Lenses in Photography which dates from the early 1950's but by now it is pretty delicate.

I wrote a magazine article (it think it was two piece) for View Camera Magazine. It only had one error in it which I corrected (a typo on Kodak WF Ektars). It was pretty good. I also have single page on the chronology of the common lenses I call Time Table of Optics.

email me, I'll send it to you

lynn@austincc.edu

Lynn

[Paul Fitzgerald]

"Reading that "the indefinable" qualities of lenses are as important as those which can be easily calculated and measured", curious questions come to my mind -really? Important to whom? To you? To all generally? To the optical designers? To all of them? To some of them? If that saying aims to claim (as it seems to do) general validity how come that optical design books don't mention this importance on the same level as those "easily" calculable properties (not that the rest of the optical design would be really so "easy" to calculate... ) ?"

Ever hear the phrase 'trade secrets', that would be all the really interesting bits that do not make it into the patent applications or publicly viewed publications.

"Were they really so generally important how come the f/64 school didn't care then?
Or is it just important to some, to you but not to the older (we're not speaking 35mm modern Nikons here... ) lens designers?
"The smoothness of the tonal transitions should be considered one of the prime criteria in choosing a lens" - you say. Nothing against your own criteria, of course, you have the right to choose them as they please you. But do you have the impression that such "smoothness" is one of the prime criteria for the majority of photographers in the history of photography? Or, even more importantly, for the optical designers of lenses?"

Please view attached photo and explain it any other way. It is an 1880's B&L f/5 Portrait Petzval re-badged H.A. Hyatt and has 17 blades, it's big brother, f/4, has 19 blades, it's cousin Unar has 19 blades, it's second cousin Tessar 1C has 21 blades and it's neighbor Vitax has 25 blades. PLEASE EXPLAIN.

Shall I? The OOF highlights take on the shape of the iris, with an even number of blades the points lay opposite points, the flats opposite flats and have a jagged look to them. With an odd number of blade the points lay opposite the flats, the flats opposite of points minimizing the effect and producing a much smoother OOF airy disc (the definition of Bokeh). Without going into boring detail it is very easy to machine an even number of pivots and slots, going with 17, 19, 21, 23, 25 is a real bother and increases production time and expense approx. 10x over even numbers.

Why would a for profit corp. increase it's expense 10 fold when the ONLY improvement would be finer look OOF if they did not care about the OOF?

[csant]

GPS, I think you can compare the discussions on "inidentifiable" qualities to a discussion on music, or fine art, in a broader picture. A first observation should be made - a caveat - that aesthetical discussions, i.e. discussions on these very qualities, are usually a rather recent phenomenon, they chime in during a later phase of the course of things, and are maybe a bit of a sign of decadence… Additionally, there is a clear distinction to be made between the technicians, and the artists - those that primarily make the instruments (and write about the making of them), and those that primarily use the instruments for artistic expression.

In the world of music, you have to basically wait until the end of the 17th century to start finding even the first hints, in the literature of the time, to non-technical, non-measurable aesthetic aspects. And those comments basically never come from instrument makers, and rarely even from composers. It's mostly the aristocrats (with too much time at their hand ;) ) that start musing about the "feelings" some music provokes in them.

Just to make one random example, J.S. Bach never mentioned anything on the beauty of a certain modulation, on the quality of a certain chord. From an acoustic point of view, it's just a matter of mathematical relationships. Nothing much to get excited about, really. Yet his music has certain qualities that not only make it easily recognizable as his, but also that make it… hm, and here one starts struggling for words… that make it more - convincing. More beautyful, if you allow me to say so… And forgive the vagueness… :)

Now photography is a rather young art. From the little I so far have learned about it, lens designers have been struggling to get their images progressively sharper over the complete image circle. Artists - erm, photographers, on the other hand, just had some tools they could use to express their "views". And these views were influenced initially by the "sister art", painting. Which, by then, had discovered (!) the qualities of non-natural representation of the world. Abstraction (in which ever form - even just in the form of "blurry" impressionism) was a conquest.

And during the high phase of this conquest into abstraction, photography comes into the game. Initially trying to follow the path the fine arts had broken - photographers initially had only the fine arts as a medium to which to relate their own art. Moving away from that abstraction, into a more "realistic", or "objective" way of representing the world, was the next conquest.

Sorry for the long digression - it was just an attempt to bring the discussion on those "inidentifiable" qualities back into some broader picture… But we are digressing.

[GPS]

GPS, I think you can compare the discussions on "inidentifiable" qualities to a discussion on music, or fine art, in a broader picture. A first observation should be made - a caveat - that aesthetical discussions, i.e. discussions on these very qualities, are usually a rather recent phenomenon, they chime in during a later phase of the course of things, and are maybe a bit of a sign of decadence…
...

Csant, in this I absolutely agree with you. :)
In fact, the more I think of it, the more I see that saying " the indefinable" qualities of lenses are as important as those which can be easily calculated and measured, or, even more, that "The smoothness of the tonal transitions should be considered one of the prime criteria in choosing a lens" is an exaggeration ad absurdum. After all, were it so important in the optical design you would first need some terminology and some standardized qualitative specification for these qualities. Now, I have never seen a description of let's say Super Angulon 65mm (or Nikon 300mm or Fuji 250mm etc. etc.) lens' smoothness of the tonal transition so that I could use this quality as "one of the prime criteria in choosing" it... It's simply absurd. If these qualities are important to you (nothing bad with that) you would first need to take some pics with it in order to be able to choose. Generally, you don't do that with lenses.
Nothing more to add...

[GPS]

...
Why would a for profit corp. increase it's expense 10 fold when the ONLY improvement would be finer look OOF if they did not care about the OOF?

What's your opinion, Paul? In another thread I tried to suggest someone's else (Ray?) explication but I have no access to the source right now and nobody else took it up. While at the topic - what's your explication of the fact that these multi aperture blades somehow vanished in later lenses? Strange because the bokeh songs did not vanish in the same way, quite the contrary.

[GPS]

"...
Why would a for profit corp. increase it's expense 10 fold when the ONLY improvement would be finer look OOF if they did not care about the OOF?

Did anybody say that nobody cared about the OOF? I must have missed that part...

[csant]

GPS, your argumentation sounds valid from a lens designer's perspective. The way I read Russ' dissertation is that he tries to bring both the technical and the artistic perspectives into the picture. His wordings here in the forum - and probably mine, too - is more of a comment from a photographer's point of view - and if you really want so (speaking for myself only, here), a 21st century's photographer. But I guess I'll first of all go back to those books about the history of the photographic lens to learn some more... :)

[GPS]

GPS, your argumentation sounds valid from a lens designer's perspective. ...
But I guess I'll first of all go back to those books about the history of the photographic lens to learn some more... :)

Absolutely right again, csant! :) Good luck in the exciting reading!

[GPS]

And all the books on genetic engineering say nothing about the shape of a young woman's leg seen as she turns to walk away. But I suspect even the genetic engineers notice it once in a while...

Surely they do...:) But none of them went so far as to genetically engineer the nicety of the legs he saw... :)

[GPS]

And all the books on genetic engineering say nothing about the shape of a young woman's leg seen as she turns to walk away. But I suspect even the genetic engineers notice it once in a while...

Although, we have to admit and to face it - on some other parts silicon is quite in a heavy use...with no so much fine engineering either... :) The beholder's eye is as unpredictable here as it is in the bokeh appreciation, I'm afraid.

[rdenney]

This bokeh argument seems to me closely related to the central argument of the nature of photographic art between Group f/64 and the pictorialists. Group f/64 wanted everything sharply rendered (at least as it is remembered today), primarily because sharp rendering was uniquely photographic vis a vis other visual arts.

The underlying principle seems to favor being true to purely photographic effects.

With the benefit of hindsight, it seems to me that selective focus (to say nothing of Petzval lenses--and the less I say there the less ignorance I will expose) is indeed a purely photographic effect. I've never seen a painting where the eyes were uniquely sharp but the tip of the nose slightly fuzzy, etc. Yes, in many paintings the eyes or face are the sharpest items in the image, but that is accomplished in a way that would be quite difficult to produce photographically, it seems to me.

But I think the argument is the same as the argument between Impressionism and Realism. Each have their own artistic intentions, and for them those respective techniques are a means to express those intentions.

Now, having decided, as the members of Group f/64 might not have done often, to throw the background significantly out of focus, one might be interested to see which lenses out there do so pleasingly. It seems to me easy enough to quantify the effect--the illumination across the disk of an out-of-focus detail--but not to characterize any particular effect as pleasing or not. That would be the subjective part.

I do not understand why it is so necessary for some folks to debate whether it was an intention of the lens designer. I'm quite sure the fellow who found a better way to sort bristles for paint brushes, or a more stable mix of titanium dioxide to make white paint, could not visualize how his work would be used by, say, Picasso.

And I also do not see why it is so important for some people to devalue the effect if they themselves don't care about it or think its important. Obviously others do.

As I've perused the archives, as I suspect most new members do, I see these arguments replayed, and it takes on a sort of Election versus Free Will sort of quality. Heaven is well-populated by believers of both those doctrines, but the nature of the argument sometimes makes one believe that the nature of salvation itself is at stake.

Most of the time, I want sharp images. Sometimes, I want to use selective focus. I never want the out-of-focus bits of an image to compete for attention with the subject.

Rick "who buys a lens, makes pictures with it, and continues to use the ones that make pleasing pictures" Denney

[GPS]

...
I do not understand why it is so necessary for some folks to debate whether it was an intention of the lens designer.
...

Obviously, others do...:)

To think that selective focus is purely a photographic effect would not be true in the history of painting. In fact, the background being completely out of focus was and is often used in the art of botanical painting. Sometimes to such a degree that photographers (sic!) try to imitate it in their works. Painters could see the effect when using their camera lucida and trying to imitate it, then the other way around when photographers saw the inspirational illustrations. No background at all is used too - both in photography and the illustrative art.

[Paul Fitzgerald]

"What's your opinion, Paul? In another thread I tried to suggest someone's else (Ray?) explication but I have no access to the source right now and nobody else took it up."

My opinion is that B&L were hunting for perfection, specifically designing for the OOF rendition and throwing down the gauntlet. Either that or they were INSANE. With 16 blades and a gang drill with 4 bits, it's 4 passes for the pivots and 8 passes for the slots. With 17 blades you cannot use a gang drill so it's 17 passes for the pivots and 17 passes for the slots only after you precision made 17 stop index plates(*) for the machines BUT it does make a perfectly round aperture very few would try to copy.

Today I don't think most people realize what an earth-shaking event the internal iris aperture was for lens makers AND what a quantum-leap it was for photography and photographers. You could now get under the dark cloth and see the DOF and OOF change before your eyes by 1/3 stops and set it to exactly what you wished. With Waterhouse stops you had to get out from under the dark cloth and go blind. Photographer were NOT going to go back the Waterhouse stops and the lens makers needed to get up to speed with building them.

" While at the topic - what's your explication of the fact that these multi aperture blades somehow vanished in later lenses? Strange because the bokeh songs did not vanish in the same way, quite the contrary."

Economics and monopoly. Only Copal is producing shutter, all the other players have left the field. The bother is that it would take Copal next to nothing to install 10 blades into a #0 or #1 size and 15 blades into a #3 size. Now if they did a limited production run of 'Artist' shutters their only problem would be trying to sell 5 blade shutters.

(*)7, 11, 13, 17, 19, 21*,23, ect are prime numbers and cannot be laid-out with compass/straight edge or set-up with a 360 degree wheel. These can only be indexed the bureau of standards way or with a 'Rose Engine', either way is an expensive pain.

[GPS]

Paul, I'm not so convinced by your economical reasons given for the disappearance of the high number of aperture blades in LF lenses. After all, their use vanished still in the time when there was no monopoly on shutter types. And the lens designers went even to much greater expenses to make lenses according to their taste (for ex. aspherical elements manufacture is more demanding than a high number blades iris...)
What is more, even the bokeh aficionados are not entirely convinced that the niceness of the bokeh is a question of the number of iris blades...
"The shape and number of a lens' diaphragm blades has little to do with bokeh. They define the shape of the blur circle, but they don't define how the light is distributed within that circle. These circles are no longer circles, but shapes with as many sides as there are blades. For instance, with five blades as most Hasselblad and Mamiya lenses one gets five-sided pentagons as the shapes of out-of-focus highlights instead of circles. This isn't too great. With six blades, most common in discount lenses for 35mm SLRs, one gets hexagons. With seven blades (most Nikkor SLR lenses) things really start to improve, since the seven-sided heptagons start looking like circles instead of recognizable shapes. Nine blades (common on Nikkor telephotos) are great, and lately they are being designed with curved blades to give a close approximation of a circle.
Odd numbers of blades will give diffraction and reflection stars around very bright points of light that have double the number of points as the number of blades. For instance, a seven-blade diaphragm will give a lovely 14-pointed star. Even numbers of blades will give stars with the same number of points as you have blades. An eight-bladed diaphragm will give a boring eight pointed star.
Again, how well one approximates a circle is only a small part of the equation. The important part is how the light is distributed. Obviously at full aperture where most people worry about this the diaphragm plays no part.
The reason some manufacturers attempt to draw a correlation between bokeh and numbers of diaphragm blades is because it's easy to see how many blades there are at the sales counter, but almost impossible to see bokeh."
(Ken Rockwell)

When it comes to Ray, with his usual academic rigeur he is very careful, stating: it is claimed that increasing the number of blades in the diaphragm to seven or even nine or more rather than the more usual five will give a "smoother" transition zone from in-focus to out of focus region. (Ray, Applied photographic optics, ) letting it on the reader to believe it or not...
For me personally, in my photography, the bokeh is as important as the color of my undies but then, personal millage varies, we all know...


"

[lungovw]

One comment about visual arts and photography: when Daguerre and Talbot came up with a way of “light printing” using lenses and chemistry, the new resource had to cope with our way of seeing that was largely shaped by painting. More eloquent than the sharp or blurred areas, for me, is the topic of perspective. It was, still is, purely a convention to represent vertical lines vertical when the horizon line is not in the middle of the image. That was created in renascence. Pretty soon camera makers provided a way to manage perspective that way also in photography. Of course they did it on purpose. Otherwise the images would not look nice to eyes trained to see the world the way Brunelleschi and others taught us to see it. No reason at all for doing that other than following the current conventions in image making.
If the way El Greco used to elongate his figures would be highly in fashion at Daguerre’s time, we would probably have the anamorphic lenses, used much later in CinemaScope, invented to sit in front of a Petzval. There are meanings for the pictorialists or f64 ways of producing images, for the frame, color palette, perspective, size, distortion… and all elements that constitute the object photography. It all belongs to our repertoire of visual representation no matter what the medium is. Photography is not isolated from that. Then I believe very much that the market demands what pleases the public and makers work to deliver it, including the number of blades in an iris. Best regards, Wagner

[rdenney]

...Otherwise the images would not look nice to eyes trained to see the world the way Brunelleschi and others taught us to see it....

I think it's more likely that both artists and photographers were responding to the same need to represent nature as people see it, while still challenging their perception of it. People know that trees are vertical, and when they are casually represented otherwise, it commands the viewer's attention. If the height of the trees is the subject, then that's fine. Since we flatten the three-dimensional world to a sheet of paper, we have to pay attention to projection issues that won't look natural to the viewer.

But people are also accustomed to looking up at objects taller than themselves. They just don't notice the perspective convergence for routine objects. But it is uniquely visible on photographs.

So, I don't think photographers were copying painters, and in the case of f/64 they were explicitly not copying painters. I think they were responding to the same need that painters also responded to by distorting perspective convergence when necessary to make the round world look natural when made flat (which may require eliminating the convergence or exaggerating it according to the artist's visualization).

And I think the same is probably true regarding such techniques as selective focus. Selective focus achieved by lack of depth of field is a tool, just as subduing the background in painting is a tool, to bring emphasis to the subject. That can be true without the photographers having copied the painters explicitly. And it can be true that lens bokeh has artistic value (for some) whether or not the designers intended it to.

Rick "agreeing that it's not (solely, or even importantly) about the number of blades, despite that Ken Rockwell agrees" Denney

[lungovw]

Denney,
It is interesting what you said because your statements: “artists and photographers were responding to the same need to represent nature as people see it” and “People know that trees are vertical, and when they are casually represented otherwise, it commands the viewer's attention”, they touch the two very different ways to approach visual representation: one is based on what you see ant the other on what you know. Visual impression very often crashes with what we know about the subject.
I agree with you that photographers were not copying painters. Both were effectively using viewers’ background in interpreting images according to current conventions. That is why they converged to similar renderings via so different ways of image making. There is a very interesting book that explores the psychological aspects of visual perception. It is Art and Illusion by Ernest Gombrich. The key point he convinced me completely is that seeing is by far more about brain than eyes’ activity. Photography is not exempt from that.

rgds

Wagner

[Emmanuel BIGLER]

(*)7, 11, 13, 17, 19, 21*,23, ect are prime numbers and cannot be laid-out with compass/straight edge

two comments on this :
- many copals have 7 blades, hence the argument about compass and straoght edge did not prevent enginers at Copal to do it ;)
- going totaly off-topic, regarding the other numbers, the story is slightly more complicated
see e.g. here http://en.wikipedia.org/wiki/Constructible_polygon
but for the satisfaction of our readers the heptadecagon (17 edges) is constructible with a compass and straight edge !!
See here in action the crazy drawing !
http://en.wikipedia.org/wiki/Heptadecagon

[GPS]

(*)7, 11, 13, 17, 19, 21*,23, ect are prime numbers and cannot be laid-out with compass/straight edge

two comments on this :
...
but for the satisfaction of our readers the heptadecagon (17 edges) is constructible with a compass and straight edge !!
See here in action the crazy drawing !
http://en.wikipedia.org/wiki/Heptadecagon

Emmanuel, you definitely take the bokeh theory to new heights!;):)

[Darryl Baird]

re: "...nature as people see it"

I think you've missed the main idea expressed from our friend Wagner in Brazil -- that people are trained to see the world in a certain way. This was just as true at the time of photography's invention, at least with regards to landscape. Early photographers knew there was a model for rendering landscapes and it was their task to satisfy that look. All artists knew the rules, yet there were still debates within the inner circles and as photographers began to provide more and more evidence that a camera is more than a mere recording machine.

Lenses evolved according to the needs of the photographers. Talbot had his lenses made by Charles Chevalier in Paris, known for the quality of both his camera obscura cameras and his optics. Early on in their relationship (1842) he states, "...all my combined glass objectives can be used for portraits and landscapes" Four years later he writes Talbot, "...The objectives for quarter plates are priced at 80F, we often add a landscape lens priced at 25F." Within that span of time the needs of the photographer were being considered and within another few years we begin to see early symmetrical lenses (to remove barrel distortion) and the earliest wide-angle lenses (Sutton) emerge, with continue development until the mid-1860s.
(*above from Talbot's letters (http://foxtalbot.dmu.ac.uk/project/project.html) and Kingslake)

The point is that photography and painting weren't so much in competition, but both were constrained by the aesthetic conventions of their own times. Painters 'rendered' the landscape and photographers 'recorded' it, yet each had the same rules going forward.

A good read on the times 1) Edwards, Steve : The Making of Englsih Photography: Allegories, 2) Taylor, Roger, Impressed By Light: British Photographs from Paper Negatives, 1840-1860, and 3) Daniel, Malcolm : “On Nature’s Invitation Do I Come”: Roger Fenton’s Landscapes”,All the Mighty World: The Photographs of Roger Fenton, 1852-1860

...also, my Kingslake edition was printed in 2004

I think it's more likely that both artists and photographers were responding to the same need to represent nature as people see it, while still challenging their perception of it. People know that trees are vertical, and when they are casually represented otherwise, it commands the viewer's attention. If the height of the trees is the subject, then that's fine. Since we flatten the three-dimensional world to a sheet of paper, we have to pay attention to projection issues that won't look natural to the viewer.

But people are also accustomed to looking up at objects taller than themselves. They just don't notice the perspective convergence for routine objects. But it is uniquely visible on photographs.

So, I don't think photographers were copying painters, and in the case of f/64 they were explicitly not copying painters. I think they were responding to the same need that painters also responded to by distorting perspective convergence when necessary to make the round world look natural when made flat (which may require eliminating the convergence or exaggerating it according to the artist's visualization).

And I think the same is probably true regarding such techniques as selective focus. Selective focus achieved by lack of depth of field is a tool, just as subduing the background in painting is a tool, to bring emphasis to the subject. That can be true without the photographers having copied the painters explicitly. And it can be true that lens bokeh has artistic value (for some) whether or not the designers intended it to.

Rick "agreeing that it's not (solely, or even importantly) about the number of blades, despite that Ken Rockwell agrees" Denney