The Leica Lens Cap Legacy, Part 1
From essential accessory to Leica logo bearer, to world’s most losable lens protector
By Jason Schneider
Oskar Barnack got it right the first time when he affixed the c.1914 Ur-Leica’s flat metal lens cap directly to the front flange of its collapsible lens by means of a slotted-head machine screw. A brutally inelegant solution perhaps, but unlike 99% of lens caps before or since it’s virtually impossible to misplace. And to deploy it you simply swing the permanently attached (but easily removable) cap in place over the front of the lens.
The Ur-Leica’s pivoting lens cap was no mere window dressing—it was an essential component of the camera because its cloth focal-plane shutter was not self-capping. In other words, if you didn’t cover the lens while winding the film to the next frame, simultaneously cocking the shutter, the open slit between the shutter curtains would pass over the film again, causing it to be light-struck and ruining at least one and possibly 2 frames.
The exquisite prototype Null-Serie (0-Series) Leica of c.1923, and the remarkably faithful O-Series Replica of 2000 have similar non-self-capping focal plane shutters and both employ the inconvenient but workable solution of having leather lens caps tethered to a little sheet metal bracket on the front of the body with a stout braided cord. To prevent the dreaded “unintended re-exposure effect” you always have to remember cap the lens while you wind to the next exposure, to which I can attest from personal experience, is a damn nuisance.
Enter the aufstecker
Leica’s first un-tethered push-on lens cap was designed to protect the collapsible 50mm f/3.5 lens fitted to the Leica I or model A, the first production Leica sold to the general public and the first to incorporate a self-capping focal plane shutter. The earliest (and rarest) examples of the non-interchangeable lenses fitted to the model A were engraved Leitz Anastigmat, which was briefly changed to Leitz Elmax in honor of Leitz’s chief optical designer Max Berek, then labeled Leitz Elmar when that classic 4-element, 3-group design was finalized. All these lenses took the original black A-36 lens cap in shiny lacquered brass and engraved with the iconic Leica logo. The A prefix in the A-36 designation stands for “aufstecker,” the lovely German word for “push-on”, and the 36 refers to 36mm, the outer diameter of the front lens surround, which was also the inner diameter of the cap mounting flange.
The ubiquitous A-36 Leica lens cap probably fits more Leica lenses than any other. It can be used on 35mm f/3.5, 50mm f/3.5, 90mm f/4, and most 135mm f/4.5 Elmars, plus 28mm f/6.3, 50mm f/2.5, and 135mm f/4.5 Hektors. Pre-war and post-war A-36 caps also fit the 35mm f/3.5 and 28mm f/5.6 Summaron, and there may be others. It’s a fascinating factoid that no Leica camera made prior to Leica II or D of 1932 (the black finished model that pioneered the ingenious built-in coupled rangefinder) bore the legendary Leica script logo with the long L, though all were dutifully engraved E. Leitz Wetzlar to denote their origin. These no-Leica Leicas include the Leica I (focal plane shutter A and Compur shutter B), the Leica I (model C) with a standardized 39mm screw mount of c. 1931, and the rangefinder-less Leica Standard (aka model E) of 1932.
To satiate the philatelic fantasies of the Leica lens cap fanatics out there I’ve included pictures of no less than 8 different delicious varieties of the Leica A-36 cap courtesy of Leica historian extraordinaire, James Lager who dug out and furnished the images. Some of the design variations, especially those in the Bakelite caps, are quite subtle, but all of them are elegant in their own distinctive way. You might think that the ultra-rare pre-1930 logo-less Leica cap with the rough textured black enamel finish is too plain and pedestrian to be beautiful, but I beg to differ. To me, its understated perfection of form harks back to the unadorned industrial minimalism of the Ur-Leica itself. But absent any identifying markings you’d need a qualified expert to certify its Wetzlarian provenance.
What possessed me to delve into the arcane realm of Leica lens caps, you ask. It all began when a generous friend gifted me with a cap-less screw mount 50mm f/3.5 coated Elmar circa 1952 and I began searching for a genuine Leica lens cap of the right vintage. The good news: I soon found a mint example in satin chrome for a paltry 18 bucks at an online retailer. But in the course of my quest, I ran into a number of oddball Leica lens caps offered at fancy prices, and that’s what piqued my curiosity.
The first one was an auction posting that offered a “Very rare original Leica lens cap for a pre-war 90mm f/2.2 Leitz Thambar soft-focus portrait lens, mint condition.” The opening bid required: $600! Now that’s a rare and pricey lens, especially if it’s in pristine shape, comes with the diffusion spot disc, the original reversible Leitz lens hood, the original lens cap that mounts over the reversed hood, and its original red cylindrical case. Still, that seemed like a lot of money for a lens cap, and I was right. When I checked back a week later the cap had been sold for a bit over half that amount—still an impressive figure.
Another unusual Leica lens cap I ran across was a handsome satin chrome rear cap for an early M-mount Leica lens with an inset center engraved Ernst Leitz GmbH, Wetzlar Germany in 2 different type sizes. According to James Lager, this is indeed a rare cap that occasionally shows up in Europe, but is seldom seen in the U.S. It’s an elegant piece that would look great on the back end of my 1950s vintage 90mm f/2 Summicron-M, but at least the plastic rear cap I’m using now is original, and adorned with the timeless Leica logo.
