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By Ked · May 2026

Collapsible 50mm Leica Lenses: M-Mount and LTM

May 2026

For me, the collapsible lenses are one of the things I really love in the Leica catalog. The mechanical ingenuity (it is not that complicated really) and the deliberate intention to make cameras as compact a possible, while retaining first class optics draws me to these lenses.

One of Leica's earliest and most enduring optical design ideas is the collapsible barrel: a 50mm lens whose middle section disappears back into the camera body when not shooting, producing a package barely larger than a body cap for transport. Pull out on the lens to extend it, give it a twist and you're ready to shoot.

The collapsible design appeared on the original Leica I in 1925 and has been part of the Leica catalog more or less continuously since. It ran through the original Elmar, the Summar and Summitar fast 50s of the 1930s and 1940s, the seminal Summicron Collapsible of 1953, and a final modern revival in the form of the Elmar-M 50mm f/2.8 (1994–2007). Each generation produced something distinct, and several of the vintage collapsibles are still usable shooting tools today.

This post walks every collapsible 50mm Leica lens worth knowing about, in both LTM (screw-mount) and M-mount, and what each one costs and shoots like in 2026.

Why Collapsible Matters

The practical case for a collapsible lens is simple: a Leica M body plus a collapsed 50mm lens is the smallest serious-camera package ever made. A Leica IIIf with a collapsed Elmar 50mm f/3.5 is as small as you might imagine for a fully featured (manually controlled) camera. An M3 with a collapsed Summicron 50mm is compact, though at about 700 grams the M3 body alone is not a lightweight camera. Compared to even the smallest mirrorless body with the smallest fixed-lens setup, the collapsed Leica setup is in a different size category.

This matters for travel and daily carry, and for anyone who has felt the friction of bringing a "real camera" out when the phone in their pocket was simply easier. A collapsed Leica isn't easy in the same way a phone is, since you still have to extend the lens, frame, focus, and meter, but it removes the size objection that keeps many serious cameras at home. And you get to control the image!

The trade-off is that a collapsible lens isn't ready to shoot the instant you raise the camera if you have it retracted. You have to extend it first. It is possible to "take photos" with the lens retracted and on a rangefinder looking through the viewfinder nothing tells you that the lens is not extended. The collapsible lenses require a certain prescence of mind to use. For me it is a matter of simple habit. If the camera (my iiig) is not in a bag or pack, the lens is extended and the lens cap is off. The camera is ready if I am.

Elmar 50mm f/3.5: The Original (1925–1959)

The collapsible mechanism itself goes back to 1923: Max Berek's five-element Anastigmat, fitted to the earliest fixed-lens Leica I cameras, could already retract into the body. Renamed Elmax once its patents cleared, then redesigned to four elements and renamed Elmar in 1926, it became the standard lens for the rest of Leica I production and, once the screw mount made lenses interchangeable, for the wider Leica system. Four elements in three groups, a Cooke triplet derivative with one element split for color correction, simple by modern standards, but Berek's optical engineering produced a lens with sharpness and contrast that defined what 35mm photography could deliver. Leitz built more than 360,000 of them in LTM alone between 1925 and 1959.

The lens went through more finish, mount, and optical changes across its run than most collectors realize. Laid out by date:

Collectors group everything before the 1951 lanthanum-glass redesign as Type I and everything after as Type II. Type I itself spans three finish/scale combinations worth knowing if you're trying to date a specific lens: nickel with the Continental aperture scale (to 1936), then chrome with the Continental scale (1936–1946), then chrome with the International scale but still a black depth-of-field marking (1947–1951). Type II is chrome, International scale, red depth-of-field marking, and lasts through the M-mount version until 1961. The M-mount lens is the same Type II optics in a different mount, not a separate design.

In a mildly interesting aside: why two different aperture progressions? Before international standardization, aperture numbering wasn't yet a single global convention. German and other European optical houses, Leitz included, rounded the underlying f-number progression to their own in-house Continental values, while a separate convention, the one used worldwide today, was converging elsewhere. Both systems represent full-stop light-halving increments; they just round the underlying math differently, which is why Continental numbers sit roughly a third of a stop apart from their International equivalents at each mark (Continental 4.5 is close to International 4, Continental 6.3 close to International 5.6, and so on), not because either measures something functionally different. International eventually won for a practical reason: once exposure meters, film-speed guides, and multi-brand camera systems all needed one number to mean the same aperture everywhere, an in-house rounding convention became a liability rather than a house style. Leitz's own switch in late 1946 or early 1947 fits into that broader postwar convergence toward the single worldwide standard still used on modern lenses.

Optically the Elmar 50mm f/3.5 is slow by modern standards (f/3.5 is two stops slower than a Summicron) but produces a specific kind of image: slightly soft wide open, sharp by f/5.6, with a low-contrast vintage rendering that some photographers actively seek out. Color rendering on coated post-war examples is warm; pre-war uncoated examples are even warmer and lower in contrast.

Shopping for one? The target spec is simple: Type II (red-scale), chrome, serial number above roughly 905,000. That combination guarantees the coated, lanthanum-glass optical formula and the International aperture scale in one lens, the best-corrected version of this lens Leitz made.

As of September 2026 we track 178 active Elmar 50mm f/3.5 LTM listings typically asking around $454, a sluggish market where half of departing listings take 43 days or more to go, and 28 active M-mount Elmar 50mm listings typically asking around $581, a steadier market at 25 days. LTM Elmars are among the most affordable Leica lenses on the entire used market.

Summar 50mm f/2 (1933–1939): Leica's First Fast Fifty

The Summar, introduced in 1933, was Leitz's first 50mm lens faster than f/2, a Max Berek six-element design. It started out as a rigid-mount lens, but Leitz moved to a collapsible mount within about a year and would even convert older rigid lenses on request, which is why rigid Summars (well under 2,000 made) barely turn up on the used market today. Early lenses were nickel; chrome took over as the standard finish by the mid-1930s.

The Summar was never factory-coated, and its oversized front element uses soft glass that scratches easily, so most surviving examples show cleaning marks. That combination gave it a reputation as one of Leitz's least-loved 50s in its day, and it's also exactly what produces the soft, glowing, low-contrast wide-open look collectors seek out now. Leitz assigned roughly 128,000 Summar serial numbers before the Summitar replaced it in 1939.

Summitar 50mm f/2 (1939–1955): The Hardened Successor

The Summitar fixed both of the Summar's weak points. A seven-element formula with a split front group improved corner performance right as color transparency film was making corner vignetting much more noticeable than it had been on black-and-white. And starting in late 1945, the Summitar became one of the first Leitz lenses to get a factory anti-reflective coating, the durability and contrast upgrade the Summar never got.

Wartime Summitars carry the military engravings to prove it: army, air force, navy (W.Haven), and Italian air force stamps all show up on surviving examples from the early 1940s. Production continued through the war, the aperture scale switched over to modern international numbering by 1946, and a six-blade hexagonal iris arrived in 1951, the source of the hexagonal bokeh collectors look for. Leitz assigned roughly 172,000 Summitar serial numbers before the Summicron took over as the flagship 50 in 1953.

Optically both lenses are character lenses. Wide open at f/2 the Summar is famously soft and glowing. Produced with uncoated glass that scratches easily, most surviving examples have visible cleaning marks that contribute to the dreamy rendering. The Summitar is sharper, higher contrast, and has a hexagonal aperture (and therefore distinctive hexagonal out-of-focus highlights). Both lenses sharpen up dramatically by f/4 and produce clean files at f/5.6 and beyond.

As of September 2026 we track 92 active Summar 50mm listings typically asking around $473, and 112 active Summitar 50mm listings typically asking around $460. The two now price within about $13 of each other: the Summitar is technically the better lens, but the Summar's "first fast Leica 50" collector appeal keeps it competitive.

Hektor 50mm f/2.5 (1930–1946): The Rare Fast Option

Max Berek named the Hektor after his own dog. It reached the Leitz catalogue in July 1930 as the only lens faster than the standard Elmar 50mm f/3.5 available for the fixed-lens Leica I Model A, which made a Model A fitted with one something of a deluxe camera at the time. Leitz built that pairing in small, largely special-order batches: only about 1,330 Model A bodies ever left the factory with a Hektor attached, across body serial numbers 38622 to 71230 in 1930 and 1931. Leitz began offering the Hektor in an interchangeable mount for the Leica I Model C later that same year, though that early mount wasn't yet standardized across bodies.

Optically the Hektor breaks from the Elmar family: six elements in three groups instead of the Elmar's four elements in three groups, which is what buys the extra reach to f/2.5 against the Elmar's f/3.5, roughly a full stop. Mechanically, though, it borrows the Elmar's own draw-tube design, so a collapsed Hektor is nearly as small as a collapsed Elmar despite the faster glass.

Like the Elmar, the Hektor got rangefinder coupling once the Leica II arrived in 1932 (the coupled version is coded HEKTORKUP), and its infinity lock moved from 11 o'clock to 7 o'clock in the same late-1932/early-1933 window as the Elmar's identical change. Nickel was the only finish through 1932; chrome took over from 1933 on. The last examples, chrome-plated but visibly lower in finish quality, were likely assembled during the war from leftover parts stock rather than kept as an active catalog item, standard practice at Leitz once wartime shortages set in.

None of that leftover-parts tail production got coated glass, and the timeline explains why. Leitz's first lens coating didn't happen until October 1941, and even then it went only into lenses issued to accredited war correspondents, not into general stock; routine factory coating across the catalog didn't start until November 1945 and wasn't applied to every current lens until March 1946. By then the Hektor wasn't a current design Leitz was retooling for anything, it was already being wound down on whatever elements were left in the parts bins. Being uncoated matters for how the lens actually shoots: every air-to-glass surface reflects a few percent of the light hitting it, and with no coating to suppress that, backlit and high-contrast scenes throw more internal reflections back at the film, showing up as flare, ghosting, and a hazier, lower-contrast image, especially wide open. The Hektor's reputation for flaring hard into the sun and rendering soft and low-contrast at f/2.5 is a direct consequence of shipping a decade before Leitz coated anything.

Both Leitz's own serial ledger and this site's lens catalog put total Hektor production at roughly 10,600 units between 1930 and 1936, a small fraction of the roughly 360,000 Elmar 50mm f/3.5 lenses Leitz built in the same stretch. That scarcity, more than any optical edge, is what drives Hektor pricing today. As of September 2026 we track 17 active Hektor 50mm listings typically asking around $1,151, and it's a dead used market: half of the ones that leave take 85 days or more to go.

Summicron 50mm f/2 Collapsible (1953–1960): The Lens That Made the Name

The Summicron grew directly out of a 1950 prototype known internally as the Summitar*, built in the Summitar's own barrel but with a new type of glass Leitz had only just finished developing in its own lab: thorium-free lanthanum glass, chosen for its unusually high refractive index without the radioactivity of the wartime-era thorium formulas other makers were still using. Leitz built only 88 of those prototypes, serials 812242 through 812329, handed them out to staff and photographers for field testing in 1952, and destroyed most of them afterward during teardown, which is why so few survive. Leitz engineers Gustav Kleinberg and Otto Zimmermann filed the patent on the resulting design in July 1950, and "Summicron" became a registered Leica trademark in January 1952, a year before the finished lens reached the catalog.

The production Summicron Collapsible carried four of its seven elements in that same lanthanum glass, a level of rare-earth content unusual for the time, built around a non-rotating collapsible helical with a click-stop iris from f/2 to f/16 and an E39 filter thread. It shipped in June 1953, confirmed by its first appearance in Leitz catalogue No. 1382 under codeword SOOIC. It outperformed nearly everything else in its class wide open at f/2, and photographers adopted it fast, cementing "Summicron" as Leitz's name for its best 50mm optics for the next seven decades.

The LTM Collapsible Summicron (order code SOOIC) ran from 1953 to 1960. The M-mount version (SOOIC-M) ran a shorter stretch, 1954 to 1957; it couldn't have started any earlier, since the M-mount itself didn't exist until the Leica M3 launched in 1954. Combined, Leitz built more than 60,000 Collapsible Summicrons across both mounts before retiring the design.

The reason for retiring it was mechanical, not optical: a telescoping barrel introduces more moving parts and more play than a fixed one, and Leitz wanted a mount that held its precision better over years of use. The direct successor was the Rigid Summicron-M, and a parallel low-volume rigid LTM version (order code SOSTA) also existed from 1960 to 1963, in numbers small enough, roughly 1,160 units, that it's now one of the scarcer Leica 50s on the used market.

Optically the Collapsible Summicron set the template later Summicrons are still judged against: sharp wide open, a warm and slightly low-contrast rendering, and smooth out-of-focus transitions that contemporary shooters still describe as the "classic Summicron look."

As of September 2026 we track 55 active Summicron 50mm Collapsible LTM listings (identified by "collapsible" in the title, since most sellers don't cite an order code) typically asking around $729, a steady market where half of departing listings are gone within 22 days, and 40 active Summicron-M 50mm Collapsible listings typically asking around $734, a slower market at 34 days. Either mount remains one of the best-value paths into Leica optics: image quality that holds up against modern lenses, in a package that collapses into a pocket, for less than most current Summicron-Ms.

Elmar 50mm f/2.8 (1957–1972): The Middle Option

Leitz designer Werner Schlapp is credited with the Elmar 50mm f/2.8's design as early as November 1954, but the lens didn't actually reach the LTM catalog until March 1957, a multi-year gap between drawing board and shipping product. It was built as a direct redesign of the aging f/3.5 Elmar, and it borrowed the new lanthanum glass that had just made its debut in the Summicron a few years earlier.

That shared glass didn't turn the f/2.8 Elmar into a second Summicron. Four elements in three groups, a simpler formula than the Summicron's seven, and by most contemporary accounts the actual gain over the f/3.5 Elmar was modest: reasonable wide open, nothing exciting, and meaningfully better once stopped down, which is typical of lenses from this era. Where it does stand out is mechanically: a chrome-plated brass barrel, a 15-blade iris, an unusually high blade count that renders out-of-focus points and highlights as smooth circles rather than polygons, and an E39 filter thread, the same one the contemporary Summicron used, so the two lenses share filters and hoods.

The LTM version (codeword ELMOO) ran from 1957 to 1966. Leitz introduced the bayonet M-mount version at Photokina in 1958 as the standard kit lens for the new Leica M2, pitched at the time as "a very economical combination," and kept the feet/international-scale variant in the catalog through 1972. Combined LTM and M-mount production stayed under 74,000 units. Leitz also prototyped a rigid-mount successor, an experimental "50mm f/2.8 Elmarit," but it never reached production. Unlike the Summicron, which did get its rigid replacement, the f/2.8 Elmar just stayed collapsible until Leitz dropped it from the catalog, with no successor until the 1994 revival.

As of September 2026 we track 27 active LTM Elmar f/2.8 listings typically asking around $490, in a dead market where half of departing listings take 96 days or more to go. The M-mount version is harder to isolate in the data (Leitz reused the same lens_family and mount for the 1994 redesign below), but the roughly 10 active listings we can identify by catalog number (11612 or 11112) in the title price similarly, around $429.

Elmar-M 50mm f/2.8 (1994–2007): The Modern Revival

Leitz let the collapsible 50mm concept sit dormant for over three decades before reviving it in 1994, and the return wasn't a standalone launch: the new Elmar-M 50mm f/2.8 debuted as the pairing lens for the limited-edition Leica M6 "J" set (1,640 units), built to mark the M system's 40th anniversary. It became a regular standalone catalog item in 1996 and stayed in production until 2007.

Leitz kept the element count identical to the 1957 original, four elements in three groups, but redesigned the lens completely around it: modern glass types, the aperture stop relocated between the second and third elements, and a non-rotating focusing mount in place of the old rotating helical. Minimum focus improved to 0.7 meters from the vintage lens's 1 meter. The result, by multiple contemporary accounts, meaningfully outperforms the 1957 lens despite sharing its basic element count, proof that a simple 65-year-old formula still had more in it.

Leitz sold it in two finishes with different materials, not just different colors: black anodized aluminum at 170 grams, and chrome-plated brass at 245 grams, a 75-gram difference worth knowing if balance on the body matters to you. It takes an E39 filter thread, with a separate lockable clip-on hood as the standard accessory. The lens also turned up in several M6 special editions, including the "Schmidt Platin," the platinum "Cartier-Bresson," and the "150 Jahre Optik."

Total production ran to roughly 17,000 units before the line ended in 2007 with a special final edition, modest volume for a lens that stayed in the catalog 13 years. By the mid-2000s it had settled in well under the contemporary Summicron-M 50mm's price (around €800 versus €1,300 in Germany in 2005), the same relative gap the current used market still shows. As of September 2026 we track 25 active Elmar-M 50mm listings (identified by catalog number 11823 or 11831 in the title) typically asking around $1,137, in a sluggish market where half of departing listings take 48 days or more to go.

For travel photographers, walk-around shooters, and anyone who has wanted a modern Summicron-quality lens on their M body in the smallest possible package, the Elmar-M 50mm f/2.8 is the right answer. The one-stop disadvantage versus the Summicron-M 50mm is the only meaningful cost; the collapsed size advantage is dramatic.

The collapsible 50mm category is one of the most under-utilized parts of the Leica catalog. Most contemporary M shooters mount a collapsible and leave the lens extended permanently, missing the size advantage that defined the system's first thirty years. If you've ever decided to leave your M body at home because it was too bulky for a particular outing, a collapsible 50mm is exactly the lens that would have made the difference.

Fair Price Comparison: Collapsible Leica 50mm Lenses

Median and fair range (25th–75th percentile) from active asking prices tracked on UsedLensTracker, as of September 2026. Special editions, bundles, and broken/parts listings excluded. Hektor and vintage Elmar f/2.8 samples are small; ranges reflect thin, collector-driven markets.

Browse current 50mm listings on UsedLensTracker across all families and mounts to find the collapsible that suits your shooting and budget.