Hand-finished Pinkham & Smith lenses?

[Mark Sawyer]

I've been reading a bit lately about how the P & S soft-focus lenses achieved their look through hand-finishing the lenses with aspherical surfaces, and that the "induced imperfections" (or whatever you may want to call them) are visible when the lenses are disassembled. Just out of curiousity, a question to those of you lucky enough to own one of those rare gems: can you see evidence of those hand-finished surfaces on the lenses?

And for the curious among you, a couple of the references I've run across lately...

From the Cooke Optics website:

"The original Pinkham & Smith lenses achieve their distinctive soft focus in a manner different from other lenses. Using the traditional glass available at the time, craftsmen hand-corrected multiple surfaces of the lenses to achieve their unique soft focus look. The introduction of aspherical surfaces gave Pinkham & Smith lenses a higher-order spherical aberration that results (when the lens was used fully open) in an image with both very high resolution and a self-luminescent quality. Cooke has reproduced the unique performance of these hand aspherized lenses using modern design techniques that duplicate this unique soft yet high-resolution performance exactly."

And from Barbara Lowery on the Greenspun lf archive, obviously talking about the PS 495 and its predecessors, at the bottom of this thread:

http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=009Djv

"What gives the Pinkham & Smith lenses their distinctive look is the reliance on hand correcting multiple surfaces of the glass, which is very different from what other lens manufacturers did. The reason P&S could get away with hand rubbing each and every piece of glass, was probably because they never made their lenses in quantities great enough to make it unfeasible to do so. It created (what our Academy Award winning chief optical designer at Cooke says is) a higher order of spherical abberation that gives the highlights that unique Pinkham & Smith luminescent quality."

and

"I originally thought that by the time the Visual Quality IV was made, it would have become an assembly line affair - I was proven wrong. The Visual Quality IV lenses Cooke took apart in England to examine revealed hand figured surfaces."

[Petzval Paul]

Hey Mark,

I have the last model, the Synthetic Series VI and the glass on the lens looks like any other. Not sure if they were still hand-polishing at that point, but their run was pretty short. Mine is serial #2777 and that was the last model they made. I suppossed if you have some electron microscope like on "Foresnsic Files" you might see something, but not with the naked eye.

The image on the ground glass, however, tells a different story... I haven't used other SF lenses but we have all seen enough Verito, Velostigmat, Heliar, etc. images to have an idea what their signiture looks are. Maybe my opinion isn't terribly objective or educated, but what I see looking through my synthetic is just optical perfection (if you are looking for SF, obviously). Sure, there are many nice lenses and some really wonderful ones, but I really, really am impressed with mine. It definately requires a learning curve to get at its potential (in my case compounded by shooting wetplate negatives), but what a potential it is!

- Paul

[Hugo Zhang]

Mark,

My Visual Quality lens has a different look than other portrait lenses of that age I have: Heliar, Dallmeyer, Hermagis Eidoscope and etc. It looks different even from the Bi-Quality lens I have. From what I read, the Visual Quality is hand finished, while the later Bi-Quality is not.

Jim Galli is an expert on this.

Hugo

[Mark Sawyer]

Thanks, guys! I have an enthusiasm for the old pictorial lenses, and while I'm lucky enough to have a few, I've never even seen a Pinkham & Smith in the flesh. I've never heard of another lens that used "hand-corrected multiple surfaces" on the glass, and wondered if they were visibly detectable. Barbara Lowry's quote made it sound as though they were. All I could think of is they may have slightly flattened some of the curve in the surface, changing the focal length ever-so-slightly along part of the face... hmmm...

Hugo ~ yes, I'm hoping Jim chimes in. I remember him once postulating his P & S might have been made by Wollensak...

Paul ~ I get everything you say! Each model of soft/diffused focus lens seems to have its own personality, which subsides subtley as you shut it down. And yes, it takes a while to learn to use them. I'm still my own worst enemy, loving the wide-open look too much to close them down to the more subtle range.

I wonder if the P & S lenses varied individually, being hand-corrected (or mis-corrected), and by some accounts, made-to-order for particular buyers...

[Jim Galli]

Sorry friends, no expert here.

Yikes, another thread to make the prices even nuttier. Was it $3200 for that Series I the other night? I'm glad that a couple of these have found their way to me.

I wouldn't be so quick to say either they are unique in a class by themselves or even that I can tell the difference readily between a couple of other favorites of mine. Alas, I don't hold out much hope of attaining the Series III I long for.

I do love the look they give. I can't remember EVER making a picture with the Pinkham that was a dud. I haven't heard that the Bi-Quality was in any way a lesser lens than it's earlier brethren. I hate to get those kinds of guesswork going on the internet when we really have nothing documented to say either way.

[Petzval Paul]

There really are no experts. Russ has done more research than probably anyone else so maybe he'll chime in, too.

For what I have understood, the Bi-quality is a superb lens, although not hand-polished, but it probably is different than a VQ. I have read that there were very subtle differnces between individual lenses, simply based on the fact that they were not being mass-produced. Indeed, that's what is so appealing about them to me. Not too sure, but I imagine that most 19th century lenses were being made by hand.

P&S lenses were definately made only by P&S, but I don't think it's impossible that the barrels were made by Wollensak. Obviously I have no information to suggest either way, so it's just speculation.

- Paul

[rknewcomb]

A long time ago in a former life, I use to grind lenses for Bausch & Lomb. It is not that difficult to make an aspherical surface. Now, knowing what aspherical surface to make and where to put it is another matter - that's probably the magic.
Robert Newcomb

[russyoung]

Mark-

(William) Pinkham & (Henry) Smith was founded about 1896 based on a claim on their letterhead. They made all sorts of optical goods and also sold scientific goods made by others (such as barometers).

F. Holland Day and his cousin Alvin Langdon Coburn were in London during 1900 to hang the benchmark exhibit "The New School of American Photography" (400 prints) and they visited with Frederick Evans while in England. Although today Evans is remembered for his sharp images of cathedrals, at the time he was also well known for his soft-focus portraits made with the Dallmeyer-Bergheim lens. Both Day and Coburn were impressed with Evans' soft focus images and they each bought a Bergheim and brought it back to Boston in August, 1901.

The Bergheim was designed for studio portraiture and at that time, no one had ever used one outside of the studio - until Day took his to Algeria (he desribes this in a 1921 letter) and produced some spectacular outdoor images of both architecture and people. In a letter addresses to Evans, dated 1908, Day explained that his friend, librarian and art-photographer Francis Watt Lee, took Day's Bergheim to Henry Smith, who "took the thing all apart & said he could do it one better in speed, but in one or two other respects he could not compete." (The Bergheim was f/9 wide-open)

Smith began making his new version; Coburn "has had half a dozen or so" and Day had five. You can visit the George Eastman House technology collection and see the original, unmarked prototype lens made for Coburn as well as several variants made especially for him (one is so marked). As to the issue of how many were made and how they were made, Day said "There are some two hundred of the things now in use here, there & everywhere & I don't have the remotest belief that any two of 'em are exactly alike- At least I have never seen the work of two which coincided even when made of the same object at the same time & this experiment has been tried by some three or four of us at Little Good Harbor, Maine."

A 1921 letter by Day to an unknown recipient (the draft copy written by an secretary is at his home in Norwood), he notes that "A story at that time (1901) gained some credence to the effect that Mr. Smith was buying up all the old single lenses of certain makes, which were to be had, and mounting them either with or without some slight changes or modifications, and that they became soft focus lenses."

I have reason to believe (and this is supported by a contemporary assessment by Heinrich Kuhn) that once Smith realized that the demand was such that it could not be filled by such stop-gap measures, he essentially copied the Taylor, Taylor and Hobson lens, RAPID VIEW AND PORTRAIT, also known as the RVP. Both Clarence White and Alfred Stieglitz used the RVP at various points in their careers. In 1913 Cooke rebranded this lens the ACHROMATIC PORTRAIT LENS. The design was not new to either TTH or Cooke but was a very slight variant of the 1839 LANDSCAPE LENS by Chevalier; the glass was of different refractive index and the aperture was opened from f/15 to f/5.6. Chevalier had deliberately closed the aperture to f/15 to control aberrations and opening it to f/5.6 allowed those very same aberrations to create a soft-focus image.

My apologies for rambling. Did I answer your question, Mark? There's much more information if I have missed the target and you can re-direct me.

Russ

[Jan Pedersen]

Keep rambling Russ, it's interesting stuff.

jan

[Jim Galli]

Couple of questions for Russ. Difference between the Bi-Quality and the Visual Quality if any? I own both. And if someone is lucky enough to own a Series III is there math calc's to adjust the visual focus to or is it all seat of the pants guessowrk that gets dialed in by experience. I have the Puyo Anachromatique and there is a bit of math (and a helpful scale on the lens) that helps you find the right place to fix the lens different from best visual focus.

Thanks for the help.

[Petzval Paul]

Dang! I completely missed that SA on Ebay! I would have bought it. *#@^%&!

Russ,

Very interesting, indeed. So initially P&S just bought up some old landscape lenses and re-mounted them? THAT's downright incredible!

Once I took my 8 and 1/2" Darlot (my shortest Petzval) and set it up in "landscape mode" without any stops to see if it would mimic a soft focus lens. It did - to a degree. Replacing it with my Synthetic, there was quite a difference. Everything took on a glow and the highlights were positively brilliant. I could see how such a lens could be used, simply polishing in the abberations that make it all interesting.

Besides those quoted in P&S catalogs, do you know of any "names" who used the Synthetic?

- Paul

[John Z.]

I would be curious to see a few examples of photos taken with the P&S lenses, if anyone has any to post on the internet.

[Mark Sawyer]

Thank you, Russ! Wonderful information, and it does answer some of my curiousities about whether the lenses varied from specimen to specimen. Sounds like they did, and Smith, Day, and others were well aware of it. I'd still love to know exactly what they were doing to which surface by hand. It may be a secret lost to time, but it seems the folks at Cooke came close with the PS945. Then again, how do you replicate something that was unique from lens to lens? If I had a better idea, I'd be tempted to hand-aspherize a surface or two on an old B&L Tessar...

I don't know that I'd like a P & S lens more than my old Veritos, Imagon, etc., as those can produce such lovely images too. But it would be fun to try...

Again, thanks for the information. We really need a "wikipedia of lf lenses" where such technical and historical information could be accumulated. So much knowledge and lore is hiding away, waiting to be lost...

[Ernest Purdum]

Amateur astronomers hand-finish their mirrors to get rid of spherical aberration. I suppose their technique might work in reverse.

Awhile back, www.surplusshed.com had CD's with lens/mirror grinding info on them. They were "closeouts" though, so may be gone by now.

If someone wants to try something of this sort with existing lenses, I nominate the various surplus copy machine lenses as good candidates. They are super cheap and reasonably fast at f4.5. C&H Sales in Pasadena, California, may still have some. You can tell the difference between them and camera lenses because their diaphragms don't close down very far. I have no idea how hard it would be to disassemble them, though.

[Toyon]

F.C. Beach also had his "multifocal" lenses hand polished to an aspherical surface, but for another purpose - he desired to increase their depth-of-field. Kingslake writes about this in his, "Lenses in Photography," book.

[Ernest Purdum]

"Increased depth of field" is just about synonymous with soft focus.

[Toyon]

"In the soft-focus lens the depth of field is greatly increased by the abberration, which is not the case when a diffusion disk is used. Professional photographers often prefer the soft-focus lens for this reason, and because the degree of diffusion can be controlled by adjusting the iris diaphragm." Rudolf Kingslake, Lenses in Photography.

"Another way to increase the depth of field is by the deliberate introduction of axial aberration. In this way each object in the scene is imaged sharply by one zone of the lens or by light of one wavelength, while all the other zones and wavelengths produce superposed images, which are to some degree out of focus and therefore less likely to be exposed on the film. Rudolf Kingslake, A History of the Photographic Lens.

What Beach found is that one can significantly increase depth of field without introducing noticeable softness - at least at low levels of enlargement.

[Hugo Zhang]

Here is something I found a while ago...

http://www.usask.ca/lists/alt-photo-process/2005/jan05/0490.htm