#9 Crown Anastigmat 300mm f4.5

20/12/2024

Christmas time is a season of miracles, and occasionally, wonders can happen even in photography. While a burning camera didn’t appear to me, something equally remarkable occurred – the resurrection of a lens and its return from the brass Limbo.

It's almost become a mantra how I start my articles with phrases like, "The only lens in the universe," "A ridiculously rare contraption," or "Rarer than hen's teeth." What can I say? I revel in the extraordinary, basking in the illusion of my own uniqueness. Enough self-defense, though - let's dive into today's lens. A piece so outrageously rare, that a careless lover of New Year's firecrackers could count them on the fingers of one hand. Presenting the completely unknown soft-focus Crown Anastigmat Series I 300mm f/4.5.

  • Once upon a time there was a company called Crown Optical Co. Rochester N.Y. (not to be confused with Crown Optical Co. Ltd. from Japan!), based in Rochester, which was once the Mecca of American optics. It housed giants like Bausch & Lomb and Kodak, as well as a myriad of smaller manufacturers.

  • Crown fell into the category of small, short-lived companies. A.H. Hatmaker founded it in 1906 with his secretary A.E. May, only to have it absorbed by the U.S. government in 1917 and incorporate into the Naval Gun Factory. Here it devoted itself entirely to the war effort, but this lasted only two years, and in the summer of 1919 Crown ceased to exist.

Out of the entire thirteen years of the factory's existence, a large part was devoted to the production of army binoculars and periscopes. Eleven, actually, because for the last two years NGF no longer produced binoculars or telescopes. Almost nothing is known about the company, the portfolio and especially the Series I line, and information is sketchy. No existing records of serial numbers, for example, are known to me, so it is very difficult to estimate the number of units produced. Given the size of the company, the short production time and the even shorter lens production, I would guess the total number of lenses produced at a few thousand. The entire Series I? Maybe a few hundred. Series I 300mm f4.5? A couple dozen at best, maybe not even that.


Soft-focus lenses have never been the core focus of any manufacturer and were typically a niche product, which was also very difficult to produce in the version with variable optical system shift (Universal Heliar, TTH Cooke, etc.). Just like in-house calibers or tourbillon in watchmaking or the Austrian Sacher, these are highly sophisticated solutions requiring extraordinary know-how.

  • The lens allows adjustment of the soft-focus effect via a separate ring, ranging from levels 1 to 4. Adjustments move part of the optical system, subtly changing the focal length and degree of diffraction, thus controlling image softness. This represents the pinnacle of optical engineering, achieved by only a few manufacturers, earning it a reputation as "nobility" among lenses. You can read about other methods of regulation and SF in general in my previous article.
  • Additionally, the lens features an anastigmat design, first developed by Dr. Paul Rudolph in 1890, known for correcting spherical aberration, astigmatism and coma. Crown's success with such advanced optical technology is doubly impressive, considering its experimental nature during that era.

Demonstration of the optical system's shift when changing the soft-focus degree.

And what about the promised return from the dead? Here's the story: the lens arrived to me from faraway lands in a frightfully dilapidated state. The SF mechanism and aperture were fortunately relatively intact, but the most crucial part, the heart of the lens - the glass itself - was hopelessly separated. I did take some photos with it, and the results looked far better than one might expect from its outward appearance. Even so, it pained me to let something so rare suffer such a sad fate, so I began pondering what could be done.

  • In this context, separation refers to the breakdown of the adhesive layer that bonds the optical elements together. Manufacturing flaws, improper storage, or who knows what else can trigger separation. It manifests in various ways, but the common symptoms are a loss of contrast, sharpness, and an increased susceptibility to stray light. The cure is singular: remove the old "glue" and re-cement the lens.
  • In the past, lenses were cemented using what's called Canada balsam. This mixture of resin from the balsam fir (Pinus balsamea) and xylene in a 1:1 ratio creates a substance with a refractive index almost identical to quartz glass. Once cured with heat, this concoction becomes clear and bonds the optical elements together without negatively impacting image quality.
  • Separation typically starts at the edges and often stays there without spreading further. It's usually yellow to orange, giving a "cracked" appearance, and in extreme cases, it can cover most of the surface. With more modern lenses that feature coatings, separation often shows up as multi-colored rainbow effects that, while visually intriguing, are still undesirable. A special case involves "flowers" - this occurs when dust particles get trapped between the lenses during the original cementing process. Over time, separation starts to spread outward from these particles, resembling delicate petals. Due to the absence of air (and thus no oxidation of the balsam), this type is colorless and somewhat aesthetically pleasing - but still a pain in the ass.

The theory of re-cementing was familiar to me, but it's much easier said than done. Just getting your hands on Canada balsam isn't exactly a walk in the park (and playing around with xylene at home is even less so). On the internet you'll find plenty of guaranteed guides on removing old adhesive by gently baking the lens in an oven (where you'll also bake the new adhesive in place) or slowly heating it in a pot of water. What these guides often leave out, however, is that you're running a high risk of thermal shock and irreparable cracking of the fragile, old glass.

  • The whole concept of "cooking" lenses reminded me of the time I, blissfully unaware, stumbled across a surprisingly detailed online recipe for making homemade napalm. At least that one mentioned that boiling a pot of gasoline on your stovetop might be somewhat precarious - and might just blow up your house. And before you ask, no, I don't remember where I found that recipe. Probably somewhere in old family cookbook.

And how do you ensure that the elements are reassembled exactly as they were before? Well, you just mark them with a pencil, of course! Except… not at all. Once again, no one tells you that the lenses need to be calibrated in both axes, X and Y. For that, you need an optical calibration bench, which - unlike a napalm-cooking pot - isn't exactly standard household equipment. If you skip this step, you risk misaligning the optical system and affecting the lens's performance. Maybe the shift will be so minor that no one notices. Or maybe not. For a standard, inexpensive Tessar or Rectilinear lens worth a few money, experimenting and inhaling xylene fumes might be justifiable. But in this case, it was too much responsibility for me.

  • I know my limits, and since I wasn't blessed with advanced knowledge of optics, I entrusted the entire project to a professional. The details are probably a closely guarded family secret, but the lenses are separated using acetylene mixtures, and instead of the long-outdated Canada balsam, they're re-cemented using special polymer adhesives or UV-cured glues. These modern materials offer superior optical properties and are far less prone to degradation over time. However, the process is reversible only with significant difficulty - or not at all.

The Crown lens consists of four cemented elements, and OF COURSE, EVERY SINGLE ONE OF THEM HAD TO BE REPAIRED. Sorry for yelling, but the odds of something like that are almost negative. Naturally, this kind of fun isn't cheap. I hemmed and hawed for a long time but ultimately gave in - just as Dante fetched Virgil from Limbo for one more journey, I decided to pull the Crown from the clutches of obscurity and grant it new adventures. You can see its resurrection compared in the photos below.

And now the most important question: how does it shoot? The SF (soft focus) settings range from 1 to 4, with level 1 being the sharpest option, free of any soft or overexposed areas. Level 4 is the maximum softness, and it's quite fascinating that even with a significant aperture stop-down, the SF effect remains easily visible - usually, such effects disappear irretrievably around f/8. Overall, the effect is subtler compared to true pictorialist lenses, so don't expect anything as extreme as a wide-open Kodak Portrait. I'd liken it more to the Bausch & Lomb Portrait Unar (yes, there will be an article on that too!). That said, this comparison isn't negative in the slightest - its rendering is particularly well-suited for portraits where you want to add just the right touch of love and softness.

All in all, this makes it a highly versatile lens thanks to the modularity of its output. Additionally, given its parameters and capabilities, it's unusually compact and lightweight (just compare it to the Universal Heliar 300mm f4.5, ha!). Unfortunately, the photos below aren't as illustrative as I'd like them to be. First, they were all taken with the SF set to 1 because the ones with stronger settings didn't turn out as I'd hoped, and I wasn't about to embarrass myself. Second, these were taken before the repair. That means reduced contrast (though that's tricky - SF lenses are inherently less contrasty, so it's hard to pinpoint what's a feature versus a defect), increased sensitivity to side light and backlight, and no direct before-and-after comparison. A proper comparison will follow later, and I'll update it here. I hope you, dear reader, will understand and forgive my impatience - the urge to write this article outweighed my ability to wait.

As the year draws to a close, I hope you're planning to dedicate the next one to shooting even more photos on the largest formats possible. I'll leave you with a phrase that applies equally to the Crown, myself, and you: "Lazarus! Rise and shoot!"