The Kobalux Wide 28mm F/3.5 LTM lens is an uncommon and uncommonly tiny Japanese lens that harkens back to old-world quality. When a fine example of the lens came through the shop on consignment last month, I knew I had to shoot it before listing it for sale. And I’m glad I did. It’s an interesting lens with an intriguing history, the sort of lens that Casual Photophile was made to explore. And for photographers searching for a tiny, collectible LTM lens with solid performance at a reasonable price, it’s an attractive option.
What is Kobalux?
The history of the Kobalux lens isn’t exactly murky. But neither is it crystal clear. Let’s start with the known facts; Kobalux is one of a number of brand names for two different lenses made by a Japanese micro-manufacturer known as Y.K. Optical, based out of Yokohama. These two lenses, a 28mm and 21mm for Leica Thread Mount (and M mount through the use of an adapter) were sold in the United States under the trademark Kobalux, and in Japan under the brand name Avenon. For many years the lenses were imported by Adorama and offered for sale in their shop. That’s what I know. The rest of what’s said about Kobalux online can’t be verified (yet – I’m working on it), and so it falls into the class of information that’s really just echoed speculation.
The internet says that Y.K. Optical was founded by a person named Mr. Abe, who is said to have been the lead lens designer at Japanese optical company Sankyō Kōki K.K., which manufactured Komura brand lenses and went out of business in 1980. So, the story goes, Mr. Abe left Sankyō Kōki K.K. when that company became insolvent in 1980. He then designed and produced the two Kobalux lenses. I’m sure that there’s someone out there who knows this history perfectly well, someone who negotiated the import deal and had tea with this Mr. Abe (Dante Stella, are you there?). If that’s you, let me know. But from where I sit, I can’t find enough information to satisfy my curiosity.
Working backward through history, we can see that Mr. Abe’s Y.K. Optical ceased operations in February, 2002. This is known from the archived Kobalux website – no longer live. On this archived site, Y.K. Optical calls their Kobalux production period a “successful seven-year run[…]” indicating that the brand was manufacturing Kobalux lenses only since 1995. But Kobalux lenses are supposed to have appeared prior to this, apparently as far back as 1982. This date does align with Abe’s reported departure from Sankyō Kōki K.K. But who was making Kobalux lenses between the years 1982 and 1995, if not Abe’s company Y.K. Optical? Some sources say that the original lenses were made by a company called “Avenon Optical.” Was this also Abe’s company?
Another wrinkle in the narrative – remember those brand names? Kobalux in North America; Avenon in Japan. Well, a search of the United States Patent and Trademark Office database returns exactly zero registered marks for Kobalux or Avenon, live or dead! So we’re unable to really trace who was making these lenses, where, and who owned the company. Reaching out to the last known email address of Kobalux returns an undeliverable mail response – the Kobalux domain is long dead.
Did the mysterious Mr. Abe really design the Kobalux lens, but sell the design to be produced by another company (perhaps the mentioned “Avenon Optical”) from 1981 to 1995? Or was it another mystery company? Was Abe the owner of both companies, and did he simply change the name of his company to Y.K. Optical in 1995, leaving the first company name lost to history? Is it possible that Abe had nothing to do with the design of this lens, and did he and his Y.K. Optical company simply purchase the existing manufacturer of Kobalux lenses in the mid-’90s? Does Abe-san even exist? Who is Mr. Abe?
I can’t answer these questions. And to be fair, answering them isn’t exactly critical. But it’s satisfying to know stuff, and not knowing stuff is frustrating. It’s also sort of my job to know this particular kind of stuff.
My usual reference materials have failed to mention Kobalux in a significant way prior to 1996, or a Kobalux-connected Mr. Abe in any way. I’m not saying that the information repeated on the internet isn’t true, but the paucity of verified fact from a reputable editor-backed photo magazine of the period is leaving this journalism minor squirming. Someone’s got to fly to Yokohama and start knocking on doors. Or dig up the guy or gal who struck the import deal at Adorama. Until that happens, the history of Kobalux isn’t gelled.
One thing about Kobalux that I know for certain is that the lens exists. I’m holding it right now. It’s definitely real. Let’s cling to that.
What is the Kobalux Wide 28mm F/3.5?
The Kobalux Wide 28mm F/3.5 is a Leica Thread Mount wide angle lens, made in the classic Japanese style – all metal, simple, compact. In fact, according to Kobalux’s archived site, the 28mm F/3.5 was the smallest 28mm LTM lens ever made as of 1996. If this isn’t true, it’s close. The Kobalux is indeed tiny.
The Kobalux Wide 28mm F/3.5 LTM used an optical formula made of six elements in four groups. The later version, made from 1995 on, is multi-coated, and has eight aperture blades. Earlier lenses, like the one I’m shooting, are single-coated and with just six aperture blades. Image quality from the two different examples is largely the same, with the later model offering slightly improved flare resistance. The lenses are rangefinder coupled, focusing from infinity to 1 meter, with a focusing tab (round in earlier lenses, crescent-shaped in later units) that rotates approximately 85º from one extreme to the other. There’s an infrared focusing mark, and a distance scale corresponding to depth-of-field scale for scale or zone focusing.
The lens is well-made and impressive, like many classic Japanese rangefinder lenses. An all-metal body is adorned with finely engraved numerals and precision knurling of the aperture ring, which is thin and clicks mechanically into its single-stop detents with a light touch. Later lenses had half-stop detents. The focusing action is smooth and precise, and very fast owing to the short throw. In many ways it feels reminiscent of the fine M Rokkor lenses made by the much larger Minolta company, a compliment to Kobalux’s manufacturing.
Simply put, the Kobalux Wide 28mm is a classic, beautiful rangefinder lens made in an era of plastic. A throwback to quality. It doesn’t feel as solid or robust as a Leica lens, but then again, Leica never made a 28mm this small or this inexpensive.
Image Quality and Sample Shots
Image quality from the Kobalux Wide 28mm F/3.5 is pretty impressive, with some caveats. Center sharpness is great at all apertures, even wide open. Corner sharpness at F/3.5 suffers, as we’d expect. But compared to old Leica LTM 28mm lenses, the Kobalux performs well in this regard. Even compared to later-developed 28mm LTM lenses, like the Voigtlander 28mm F/3.5 Color Skopar from 2002, the Kobalux is a comparable performer (and the Kobalux is smaller, too). As we stop down the aperture, the corners sharpen up as we’d expect. By F/8 we’re seeing uniform sharpness across the frame. Standard stuff, but impressive from what was by all measures a small manufacturer.
Vignetting is pretty heavy, and what’s surprising is that this vignetting doesn’t improve as drastically as it does with other wide angle lenses I’ve used. Even at F/5.6 we’re still seeing significant vignetting. At F/8 there’s still vignetting! It’s pretty wild. Vignetting can be helped away in digital post-processing, or used to accentuate a subject, so I don’t see this being the most egregious offense that a lens can make. But it’s worth noting.
Flares, even in my single-coated early version, are well-handled. Shooting directly into the sun will create flares. But there are few lenses made which can claim otherwise. Photographers who are bothered by flares should use a screw in lens hood, or avoid pointing the glass at the overbearing and enormous sphere of hot plasma that greedily accounts for 99.86% of the total mass of our solar system. I guess I shouldn’t complain. The Sun was here 4.6 billion years before the Kobalux.
Bokeh doesn’t really impress, but there are few 28mm lenses with impressive bokeh. Highlight bokeh looks okay, and it’s possible to get nice subject isolation when shooting at the lens’ minimum focus distance. But really, the 28mm lens is made for contextual photography. Landscapes, street photography, portraits in which the background is as important as the subject – this is where the 28mm lens works, and this is no different with the Kobalux. Set it at F/8 and, as the old adage goes, be there. Shot in this way, the Kobalux Wide 28mm F/3.5 leaves little to be desired.
[More digital sample shots will be added to this post in the next 24 hours, dear reader. Check back tomorrow if that’s helpful for you. For now – Deadlines!]
An uncommon, finely made Japanese LTM lens at a relatively low cost? The Kobalux Wide is all of that. In its own time it was a strong value proposition, and today, when digital mirrorless cameras can easily adapt any lens made in the last eighty years, its value remains. While there are cheaper options available from other Japanese brands, Canon for example, these lack the Kobalux’s rarity. For anyone seeking a bit of photographic history, a bit of an oddball with character, and a decent deal on a high performer for their LTM mount film or digital mirrorless camera, it’s smart to consider the Kobalux Wide 28mm F/3.5.
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