Jason Schneider
the Camera Collector
Evolution of the Lens Mount: The Golden Age is Now!
Lens mounts used to be exclusive, but mirrorless changed everything
By Jason Schneider
During the glorious era of film camera supremacy, a reign of more than a century that came to a whimpering halt with the dawn of the digital dominance in the early 2000s, lenses (with few exceptions) were not interchangeable among different brands of cameras. Photographers chose a system (or maybe 2 or 3) and stuck with them because doing otherwise would be inconvenient and financially untenable. Options for rangefinder Leica, Contax, Nikon, and Canon lenses were especially limited because they couldn’t be adapted to 35mm SLRs except for shooting ultra closeups, and 35mm SLR lenses were virtually useless on 35mm rangefinder cameras since they didn’t offer any convenient rangefinder coupling method. Back in those days Modern Photography, the US top magazine dedicated to serious photo gear geeks, ran a yearly article on the few relatively few camera lens adapters then available.
Today, largely thanks to mirrorless cameras with short flange focal distances of 20mm or less, and the ability to focus any lens, in Live View via the LCD or EVF, virtually any lens you can physically mount on the camera will focus to infinity and be perfectly useable. Indeed, there are now literally hundreds of camera company and third-party adapters that will let you mount virtually any lens on any mirrorless camera, some with full AF, AE, and multimode functionality via built-in contacts; others with more limited aperture-priority autoexposure and manual focus capability. While DSLRs don’t provide as much inherent inter-system compatibility because their longer flange focal distances, there are now scores of adapters that will let you mount many DSLR and SLR lenses on other DSLRs, SLRs, and mirrorless cameras. Convenience and functionality may vary but in most cases the transition is seamless. Compared to the old days of siloed and incompatible lens systems, it sure feels like we’re the golden age, and the limitless possibilities of mounting ancient vintage lenses on cutting edge digital cameras or cherished optical classics from one system on cameras made by its leading competitors, seem like a dream come true.
Lens Mounts For Mirrorless Cameras: There are literally hundreds off them that allow you mount and shoot almost any lens, including vintage classics!
The first real break in the wall of SLR lens mount incompatibility came from independent lens makers such as Tamron, Sigma, and Vivitar. They all had a vested interest in supplying lenses to as wide an audience as possible, and up to that point they’d been turning out different versions of their lenses in each of the major mounts. This was not only expensive and inconvenient, but also tended to build up unsold inventories of lenses in mounts that didn’t sell as well as expected. Then, in the mid ‘70s Tamron came out with the aptly named Adaptall system, which allowed standardized lens bodies to be adapted to work a variety of camera mounts by fitting suitable Adaptall adapters. Unlike its earlier Adapt-A-Matic mount system Tamron Adaptall mounts enabled auto diaphragm operation and full aperture metering and provided substantial benefits to photographers and retailers alike. Adaptall Custom adapters were available for virtually all SLR mounts in the ‘70s and ‘80s, including Canon FD, Minolta MD, Konica AR, Contax/Yashica, Olympus OM, Nikon AI, M42. Pentax K, Fujica FT, Topcon RE, Mamiya SX, Rollei, Leica R, and Practica. In 1979, they marketed the slightly modified Adaptall-2 system that transmits the lenses’ maximum aperture to the camera, improving functionality with Canon FD-, Minolta MD-, and Konica AR-series cameras. Other workable interchangeable mount systems were the Sigma Y/S, basically a T-mount system with a Pentax screw mount-type aperture stop-down pin added, and the Vivitar T-4, which required setting the lens aperture ring to one index mark for Pentax, Nikon, Canon, Miranda, Petri FT and Exakta mount lenses, or another index mark for Minolta, Topcon , and Leicaflex lenses, and (with the latter group) setting a meter coupling pin on the mount adapter before mounting it on the lens. Both these stems worked well but neither was as comprehensive or as successful as Tamron’s Adaptall.
The flange focal distance (FFD): The key to maximum flexibility
The real breakthrough in almost unlimited lens interchangeability began with the widespread popularity of DSLRs in the early 2000s and really exploded with the dominance of mirrorless cameras, which are now in the technological forefront. The reason mirrorless cameras opened the floodgates is that, by eliminating the bulky mirror box and flipping reflex mirror, they’re able to provide a much shorter lens flange-to-image-sensor distances, aka the flange focal distance (FFD), which vastly increases the number of non-native lenses that can be mounted and used with full functionality.
A camera with a short FFD can use lenses meant for virtually any camera with a longer FFD by using a simple adapter that adds the extra distance so the lens can focus correctly. For example, an L-mount mirrorless camera has an FFD of 20.0mm and a Nikon F-mount lens has an FFD of 46.5mm. so, by adding an adapter with a width of 26.5mm the Nikon lens can be used on an L-mount mirrorless camera.
Unfortunately, it doesn’t work the other way around. There’s no such thing as an adapter that removes 26.5mm and would allow you to use, for example, L-mount lenses directly on a Nikon F-mount camera without any operational or technical restrictions. In short, the general rule is that a mount with a shorter FFD can use lenses with a longer FFD so long the proper adapter is used, except in rare cases where the rear of the lens protrudes far enough back inside the camera to interfere with a DSLR’s mirror.
There are 2 ways you can mount lenses designed for a shorter FFD on a camera with a longer FFD. 1. Use an adapter that acts like an extension tube, which allows the lens to focus to close distances, but not to infinity. 2. Use an adapter that includes a corrective lens or lenses that lets you focus to infinity. Adapters of the latter type usually act like tele-converters so the resulting image is magnified (cropped) and the extra glass tends to reduce image quality.
Here are some typical flange focal distances for mirrorless and DSLR cameras that will give you a good idea of the differences:
Mirrorless mount Flange focal distance
Nikon Z 16.0mm – current king of adaptability
Canon EF-M 18.0mm
Canon RF 20.0mm
Sony E 18.0mm
Micro Four Thirds 19.25mm
DSLR mount Flange focal distance
Canon EF 44.0mm
Minolta/Sony A 44.5mm
Pentax K 45.46mm
Nikon F 46.5mm
Olympus OM 46.0mm
Despite the restrictions due to longer FFDs, there are scores of SLR and DSLR lens adapters currently available, ranging from simple physical mount adapters to those with contacts and connections that provide full AF, image stabilization, and other built-in camera system functions. And there are literally hundreds of current lens adapters that let you use most current and legacy lenses, as well as many vintage classic lenses, on your mirrorless marvels. These also run the gamut from simple mechanical devices that simply let you mount the lens, to full-function adapters with contact arrays that provide AF, AE, IS and other capabilities. It’s not possible to mention them all here but here’s a short list of leading camera companies and independent companies that make lens adapters, and a representative sample of their offerings.
Major camera companies that make lens adapters under their own name include Nikon, Canon, Sony, Sigma, Hasselblad, and Leica. The top names among independent companies marketing lens adapters include FotodioX, Rayqual, Kipon, Vello, Metabones, Vitrox, Commlite, K&FConcept, and Fringer.
Here are 8 current lens adapters in both categories:
Canon Control Ring Mount Adapter EF-EOS R: Maintains AF and Image Stabilization, Configurable Control Ring, Dust- and Water-Resistant, $199.00.
Vello Canon EF/EF-S to Sony E-Mount Camera Auto Lens Adapter: Works with Full-Frame & APS-C Formats, Enables AF and AE, Supports USM and STM Focusing Motors. $99.00.
Nikon FTZ II Mount Adapter: Nikon F Lens to Nikon Z-mount cameras: Streamlined design with no tripod mount, Maintains AF/AE with E, G, D-type lenses, $249.95.
Vitrox EF-M2 II Canon EF to Micro Four Thirds Camera Mount Adapter: Built-in Focal Reducer, 0.7x Magnification, one stop increase in lens aperture, $149.00.
Sigma NC-21 Mount Converter/Lens Adapter Sigma/ Canon EF-Mount lenses to L-Mount camera: Integrated LED display compatibility, maintains AF and AE, supports In-Camera Correction Features, $199.95.
FotodioX Pro Lens Mount Adapter M42 lens to Canon EF-Mount Camera: Maintains infinity focus, Leaf Spring Mount Design, Brass with Stainless Steel Finish, $14.95.
Metabones Nikon F Lens to Sony E-mount Camera T Adapter II (black): Brass construction with chrome plating, flocked interior to limit flare, infinity focus, $99.00.
Fringer EF-FX Pro II Lens Mount Adapter for EF- or EF-S Mount Lens to Fujifilm X-Mount Camera: Built-in Electronic Aperture Adjustment, Phase-Detection AF Supported, brass bayonets, $349.00.
Evolution of the lens mount: A Brief Retrospective
Ancient times
In the late 19[SUP]th[/SUP] and early 20[SUP]th[/SUP] centuries, before there was any such thing as a 35mm still camera, most pros and serious photographers used large format view cameras, so you to use practically any lens you wanted so long as you could mount it in a compatible lensboard, and it covered the format. Lenses were essential, but they were typically marketed as separate view camera accessories. Other types of cameras of that era, ranging from simple box cameras to high-end folders and reflex cameras, typically had fixed (noninterchangeable) lenses.
The first interchangeable lens 35? Maybe.
Without getting into the weeds of “What was the first interchangeable lens 35mm camera?” let’s just say that back in 1931 Leitz introduced a threaded lens mount measuring 39mm x 26tpi (threads per inch) with a flange focal distance of 28.8mm on the Leica I (Model C) in anticipation of its first interchangeable lens rangefinder camera, the Leica II (or D) of 1932. This combination of a metric diameter with an English Imperial (Whitworth) pitch of about 0.977mm was said to be designed (by Oskar Barnack) to forestall, at least temporarily, competition from aftermarket lenses being used on the forthcoming Leica screw-mount rangefinder cameras. Although the design was patented, other optical companies (such as Meyer) were tacitly granted permission to use it, and others swiftly pirated it and introduced lenses with the new 39mm thread, now known as LTM (Leica Threaded Mount) or M39. It was undoubtedly the first widely adopted lens mount for interchangeable lens 35mm photography.
Eventually there were scads of Leica copies beginning with the Russian Fed of 1934, a faithful but mediocre copy of the Leica II (Model D), and a host of Japanese Leica clones of the ‘50s, thanks to German patents being voided after WWII and Japanese companies encouraged to copy them by none other than General MacArthur and company. A stellarexample: the glorious bottom-loading screw mount Canons of the ‘50s, which were a lot more than mere copies. All these companies, as well as Nikon, Konishiroku (Konica) Tanaka Optical, Sun, Schneider,Meyer, and even Zeiss (and many others), offered rangefinder coupled lenses in Leica screw mount.
The first bayonet mount 35? Possibly.
In 1932, Zeiss Ikon brought forth the Contax I with a bayonet mount that had a focusing helical built into the camera body. The mount was used in the Contax II, III, IIa, and IIIa until the Contax rangefinder line was sadly phased out in 1961, and it was adopted in slightly modified form by Nikon for their superb series of S-series rangefinder cameras up to and including the S3, S4, and the landmark Nikon SP of 1957.
The Leica (LTM) screw mount and the Contax/Nikon bayonet mount were incompatible and there was no adapter that let you mount LTM lenses on a Contax or vice versa. In short, you paid your money and made your choice. A glimmer of future possibilities was the brilliant Leica M bayonet mount introduced on the Leica M3 of 1954. A masterfullyengineered,4-lobed bayonet, it was designed to allow almost all LTM screw-mount lenses to be used on M-mount Leicas by using a simple screw mount to M-bayonet adapter that screwed onto the existing male LTM mount on the back of the lens—a stunning and effective example of non-obsolescence and a key element in the Leica M’s success.There were other rangefinder 35s with unique non-compatible lens mounts, including the Steinheil Casca, Robot (screw type), and the Robot Royal (bayonet), but all were produced in limited quantities.
Non-compatible SLR mounts
The lack of inter-system lens interchangeability extendedwell into the 35mm SLR era. The Exakta bayonet mount introduced in 1936 (and later adopted in modified but compatible form by Topcon) was totally incompatible with the M42 mount, a 42mmm diameter screw mount that was first seen on the Praktika and PraktiflexSLRs of the late ‘30s and was later adopted by Pentax, Ricoh, Olympus, et al. And there were a host of other one-off lens mounts including the Praktina (bayonet) and Rectaflex (bayonet). The Nikon F bayonet mount that debuted in 1959 was not compatible with any of thosepreviously mentioned, nor with the Canonflex, Canon FL, or Canon FD mounts. Olympus soon switched to the OM mount and Pentax later adoptedthe K-mount, adding to the confusion. Everyone jealously guarded their proprietary mounts in the belief that they would ensure a captive audience for their lenses—convenience for the consumer be damned.
From the perspective of the 1960s we appeared to be doomed to a cacophonous profusion of competing incompatible lens mounts. While the 1970s offered a glimmer of hope in the form of interchangeable lens mount systems, the main reason everything changed after about 2002 was the advent of digital photography and its frenetic development cycle based on the electronics paradigm. That led to (among other things) the perfection of the EVF, high-performance image sensors, and astonishing image processing software, all of which ushered in the rise of the mirrorless camera. That is what made today’s Golden Age of Lens Interchangeability possible.
Lens mounts used to be exclusive, but mirrorless changed everything
By Jason Schneider
During the glorious era of film camera supremacy, a reign of more than a century that came to a whimpering halt with the dawn of the digital dominance in the early 2000s, lenses (with few exceptions) were not interchangeable among different brands of cameras. Photographers chose a system (or maybe 2 or 3) and stuck with them because doing otherwise would be inconvenient and financially untenable. Options for rangefinder Leica, Contax, Nikon, and Canon lenses were especially limited because they couldn’t be adapted to 35mm SLRs except for shooting ultra closeups, and 35mm SLR lenses were virtually useless on 35mm rangefinder cameras since they didn’t offer any convenient rangefinder coupling method. Back in those days Modern Photography, the US top magazine dedicated to serious photo gear geeks, ran a yearly article on the few relatively few camera lens adapters then available.
Today, largely thanks to mirrorless cameras with short flange focal distances of 20mm or less, and the ability to focus any lens, in Live View via the LCD or EVF, virtually any lens you can physically mount on the camera will focus to infinity and be perfectly useable. Indeed, there are now literally hundreds of camera company and third-party adapters that will let you mount virtually any lens on any mirrorless camera, some with full AF, AE, and multimode functionality via built-in contacts; others with more limited aperture-priority autoexposure and manual focus capability. While DSLRs don’t provide as much inherent inter-system compatibility because their longer flange focal distances, there are now scores of adapters that will let you mount many DSLR and SLR lenses on other DSLRs, SLRs, and mirrorless cameras. Convenience and functionality may vary but in most cases the transition is seamless. Compared to the old days of siloed and incompatible lens systems, it sure feels like we’re the golden age, and the limitless possibilities of mounting ancient vintage lenses on cutting edge digital cameras or cherished optical classics from one system on cameras made by its leading competitors, seem like a dream come true.
Lens Mounts For Mirrorless Cameras: There are literally hundreds off them that allow you mount and shoot almost any lens, including vintage classics!
The first real break in the wall of SLR lens mount incompatibility came from independent lens makers such as Tamron, Sigma, and Vivitar. They all had a vested interest in supplying lenses to as wide an audience as possible, and up to that point they’d been turning out different versions of their lenses in each of the major mounts. This was not only expensive and inconvenient, but also tended to build up unsold inventories of lenses in mounts that didn’t sell as well as expected. Then, in the mid ‘70s Tamron came out with the aptly named Adaptall system, which allowed standardized lens bodies to be adapted to work a variety of camera mounts by fitting suitable Adaptall adapters. Unlike its earlier Adapt-A-Matic mount system Tamron Adaptall mounts enabled auto diaphragm operation and full aperture metering and provided substantial benefits to photographers and retailers alike. Adaptall Custom adapters were available for virtually all SLR mounts in the ‘70s and ‘80s, including Canon FD, Minolta MD, Konica AR, Contax/Yashica, Olympus OM, Nikon AI, M42. Pentax K, Fujica FT, Topcon RE, Mamiya SX, Rollei, Leica R, and Practica. In 1979, they marketed the slightly modified Adaptall-2 system that transmits the lenses’ maximum aperture to the camera, improving functionality with Canon FD-, Minolta MD-, and Konica AR-series cameras. Other workable interchangeable mount systems were the Sigma Y/S, basically a T-mount system with a Pentax screw mount-type aperture stop-down pin added, and the Vivitar T-4, which required setting the lens aperture ring to one index mark for Pentax, Nikon, Canon, Miranda, Petri FT and Exakta mount lenses, or another index mark for Minolta, Topcon , and Leicaflex lenses, and (with the latter group) setting a meter coupling pin on the mount adapter before mounting it on the lens. Both these stems worked well but neither was as comprehensive or as successful as Tamron’s Adaptall.
The flange focal distance (FFD): The key to maximum flexibility
The real breakthrough in almost unlimited lens interchangeability began with the widespread popularity of DSLRs in the early 2000s and really exploded with the dominance of mirrorless cameras, which are now in the technological forefront. The reason mirrorless cameras opened the floodgates is that, by eliminating the bulky mirror box and flipping reflex mirror, they’re able to provide a much shorter lens flange-to-image-sensor distances, aka the flange focal distance (FFD), which vastly increases the number of non-native lenses that can be mounted and used with full functionality.
A camera with a short FFD can use lenses meant for virtually any camera with a longer FFD by using a simple adapter that adds the extra distance so the lens can focus correctly. For example, an L-mount mirrorless camera has an FFD of 20.0mm and a Nikon F-mount lens has an FFD of 46.5mm. so, by adding an adapter with a width of 26.5mm the Nikon lens can be used on an L-mount mirrorless camera.
Unfortunately, it doesn’t work the other way around. There’s no such thing as an adapter that removes 26.5mm and would allow you to use, for example, L-mount lenses directly on a Nikon F-mount camera without any operational or technical restrictions. In short, the general rule is that a mount with a shorter FFD can use lenses with a longer FFD so long the proper adapter is used, except in rare cases where the rear of the lens protrudes far enough back inside the camera to interfere with a DSLR’s mirror.
There are 2 ways you can mount lenses designed for a shorter FFD on a camera with a longer FFD. 1. Use an adapter that acts like an extension tube, which allows the lens to focus to close distances, but not to infinity. 2. Use an adapter that includes a corrective lens or lenses that lets you focus to infinity. Adapters of the latter type usually act like tele-converters so the resulting image is magnified (cropped) and the extra glass tends to reduce image quality.
Here are some typical flange focal distances for mirrorless and DSLR cameras that will give you a good idea of the differences:
Mirrorless mount Flange focal distance
Nikon Z 16.0mm – current king of adaptability
Canon EF-M 18.0mm
Canon RF 20.0mm
Sony E 18.0mm
Micro Four Thirds 19.25mm
DSLR mount Flange focal distance
Canon EF 44.0mm
Minolta/Sony A 44.5mm
Pentax K 45.46mm
Nikon F 46.5mm
Olympus OM 46.0mm
Despite the restrictions due to longer FFDs, there are scores of SLR and DSLR lens adapters currently available, ranging from simple physical mount adapters to those with contacts and connections that provide full AF, image stabilization, and other built-in camera system functions. And there are literally hundreds of current lens adapters that let you use most current and legacy lenses, as well as many vintage classic lenses, on your mirrorless marvels. These also run the gamut from simple mechanical devices that simply let you mount the lens, to full-function adapters with contact arrays that provide AF, AE, IS and other capabilities. It’s not possible to mention them all here but here’s a short list of leading camera companies and independent companies that make lens adapters, and a representative sample of their offerings.
Major camera companies that make lens adapters under their own name include Nikon, Canon, Sony, Sigma, Hasselblad, and Leica. The top names among independent companies marketing lens adapters include FotodioX, Rayqual, Kipon, Vello, Metabones, Vitrox, Commlite, K&FConcept, and Fringer.
Here are 8 current lens adapters in both categories:
Canon Control Ring Mount Adapter EF-EOS R: Maintains AF and Image Stabilization, Configurable Control Ring, Dust- and Water-Resistant, $199.00.
Vello Canon EF/EF-S to Sony E-Mount Camera Auto Lens Adapter: Works with Full-Frame & APS-C Formats, Enables AF and AE, Supports USM and STM Focusing Motors. $99.00.
Nikon FTZ II Mount Adapter: Nikon F Lens to Nikon Z-mount cameras: Streamlined design with no tripod mount, Maintains AF/AE with E, G, D-type lenses, $249.95.
Vitrox EF-M2 II Canon EF to Micro Four Thirds Camera Mount Adapter: Built-in Focal Reducer, 0.7x Magnification, one stop increase in lens aperture, $149.00.
Sigma NC-21 Mount Converter/Lens Adapter Sigma/ Canon EF-Mount lenses to L-Mount camera: Integrated LED display compatibility, maintains AF and AE, supports In-Camera Correction Features, $199.95.
FotodioX Pro Lens Mount Adapter M42 lens to Canon EF-Mount Camera: Maintains infinity focus, Leaf Spring Mount Design, Brass with Stainless Steel Finish, $14.95.
Metabones Nikon F Lens to Sony E-mount Camera T Adapter II (black): Brass construction with chrome plating, flocked interior to limit flare, infinity focus, $99.00.
Fringer EF-FX Pro II Lens Mount Adapter for EF- or EF-S Mount Lens to Fujifilm X-Mount Camera: Built-in Electronic Aperture Adjustment, Phase-Detection AF Supported, brass bayonets, $349.00.
Evolution of the lens mount: A Brief Retrospective
Ancient times
In the late 19[SUP]th[/SUP] and early 20[SUP]th[/SUP] centuries, before there was any such thing as a 35mm still camera, most pros and serious photographers used large format view cameras, so you to use practically any lens you wanted so long as you could mount it in a compatible lensboard, and it covered the format. Lenses were essential, but they were typically marketed as separate view camera accessories. Other types of cameras of that era, ranging from simple box cameras to high-end folders and reflex cameras, typically had fixed (noninterchangeable) lenses.
The first interchangeable lens 35? Maybe.
Without getting into the weeds of “What was the first interchangeable lens 35mm camera?” let’s just say that back in 1931 Leitz introduced a threaded lens mount measuring 39mm x 26tpi (threads per inch) with a flange focal distance of 28.8mm on the Leica I (Model C) in anticipation of its first interchangeable lens rangefinder camera, the Leica II (or D) of 1932. This combination of a metric diameter with an English Imperial (Whitworth) pitch of about 0.977mm was said to be designed (by Oskar Barnack) to forestall, at least temporarily, competition from aftermarket lenses being used on the forthcoming Leica screw-mount rangefinder cameras. Although the design was patented, other optical companies (such as Meyer) were tacitly granted permission to use it, and others swiftly pirated it and introduced lenses with the new 39mm thread, now known as LTM (Leica Threaded Mount) or M39. It was undoubtedly the first widely adopted lens mount for interchangeable lens 35mm photography.
Eventually there were scads of Leica copies beginning with the Russian Fed of 1934, a faithful but mediocre copy of the Leica II (Model D), and a host of Japanese Leica clones of the ‘50s, thanks to German patents being voided after WWII and Japanese companies encouraged to copy them by none other than General MacArthur and company. A stellarexample: the glorious bottom-loading screw mount Canons of the ‘50s, which were a lot more than mere copies. All these companies, as well as Nikon, Konishiroku (Konica) Tanaka Optical, Sun, Schneider,Meyer, and even Zeiss (and many others), offered rangefinder coupled lenses in Leica screw mount.
The first bayonet mount 35? Possibly.
In 1932, Zeiss Ikon brought forth the Contax I with a bayonet mount that had a focusing helical built into the camera body. The mount was used in the Contax II, III, IIa, and IIIa until the Contax rangefinder line was sadly phased out in 1961, and it was adopted in slightly modified form by Nikon for their superb series of S-series rangefinder cameras up to and including the S3, S4, and the landmark Nikon SP of 1957.
The Leica (LTM) screw mount and the Contax/Nikon bayonet mount were incompatible and there was no adapter that let you mount LTM lenses on a Contax or vice versa. In short, you paid your money and made your choice. A glimmer of future possibilities was the brilliant Leica M bayonet mount introduced on the Leica M3 of 1954. A masterfullyengineered,4-lobed bayonet, it was designed to allow almost all LTM screw-mount lenses to be used on M-mount Leicas by using a simple screw mount to M-bayonet adapter that screwed onto the existing male LTM mount on the back of the lens—a stunning and effective example of non-obsolescence and a key element in the Leica M’s success.There were other rangefinder 35s with unique non-compatible lens mounts, including the Steinheil Casca, Robot (screw type), and the Robot Royal (bayonet), but all were produced in limited quantities.
Non-compatible SLR mounts
The lack of inter-system lens interchangeability extendedwell into the 35mm SLR era. The Exakta bayonet mount introduced in 1936 (and later adopted in modified but compatible form by Topcon) was totally incompatible with the M42 mount, a 42mmm diameter screw mount that was first seen on the Praktika and PraktiflexSLRs of the late ‘30s and was later adopted by Pentax, Ricoh, Olympus, et al. And there were a host of other one-off lens mounts including the Praktina (bayonet) and Rectaflex (bayonet). The Nikon F bayonet mount that debuted in 1959 was not compatible with any of thosepreviously mentioned, nor with the Canonflex, Canon FL, or Canon FD mounts. Olympus soon switched to the OM mount and Pentax later adoptedthe K-mount, adding to the confusion. Everyone jealously guarded their proprietary mounts in the belief that they would ensure a captive audience for their lenses—convenience for the consumer be damned.
From the perspective of the 1960s we appeared to be doomed to a cacophonous profusion of competing incompatible lens mounts. While the 1970s offered a glimmer of hope in the form of interchangeable lens mount systems, the main reason everything changed after about 2002 was the advent of digital photography and its frenetic development cycle based on the electronics paradigm. That led to (among other things) the perfection of the EVF, high-performance image sensors, and astonishing image processing software, all of which ushered in the rise of the mirrorless camera. That is what made today’s Golden Age of Lens Interchangeability possible.
Bill Clark
Mentor
Back in the late 1960’s I worked during the summer in the camera department at Target. It was their second store located in St. Louis Park Minnesota. They carried Vivitar lenses that you could buy various adaptors to work on most film slr cameras back then. I still have a 28 and a 35 with the adaptor to fit my Nikkormat camera. The adaptor even has the coupling so as it works with the light meter on my camera.
ranger9
Well-known
There wasn't? Head Bartender says there were such from Orion and Cooke & Perkins in the '50s: https://www.cameraquest.com/adapter.htm
ZivcoPhoto
Well-known
I bought a Vivitar 200mm F3.5 preset lens from 47 Street Photo in 1968 for my Nikon F. I still have the T-mount and the screw on Ponder & Best lens cap and a few of the glass elements. I think the focus helical failed on the lens after some years.
Out to Lunch
Menteur
In addition to the above, the EVFs on the newer mirrorless cameras have improved tremendously. On the Leica SL2-S, you can easily focus manual lenses without focus peaking. Cheers, OtL
Hibbs
R.I.P. Charlie
I've fallen deeply into the rabbit hole that is adapting lenses to Fuji X. One lens that I [recently] took a flyer on was an Argus Sekor 58mm f1.7. I grabbed this lens as I thought I could change the [short-lived] Argus mount to M42. This lens was made for Argus but also made for a Mamiya SLR [as Mamiya-Sekor 58mm f1.7]
When I received the lens. I inspected the mount to see what the conversion might entail. The bayonet look very similar to the Konica AR mount. Just on a chance I tried mounting the lens onto a K&F adapter [AR - FX] and wouldn't you know it, it fit. There ws no wobble but just a small amount of play at rotation.
So, I mounted it onto the Fuji X and everything appeared fine. Focus to infinity and close focusing.
Originally the idea was to get it to M42 to use on film, but for now I think I'll just leave it be.
When I received the lens. I inspected the mount to see what the conversion might entail. The bayonet look very similar to the Konica AR mount. Just on a chance I tried mounting the lens onto a K&F adapter [AR - FX] and wouldn't you know it, it fit. There ws no wobble but just a small amount of play at rotation.
So, I mounted it onto the Fuji X and everything appeared fine. Focus to infinity and close focusing.
Originally the idea was to get it to M42 to use on film, but for now I think I'll just leave it be.
John Shriver
Well-known
The patented aspect of Leica's LTM mount was the rangefinder coupling. Which is why the Contax rangefinders use the Byzantine method of rangefinder coupling via rotation of the mount for the 50mm lens. Leica apparently didn't enforce it against lens makers, but certainly nobody made a compatible camera until after WW-II when German patents were invalidated internationally as a war reparation. That's when Canon started making rangefinder-coupled LTM cameras.
Benjamin Marks
Mentor
One interesting addition. There are now also helical mounts that turn the adapter into something of a mini-extension tube. So if you always chafed at the minimum focus distance, say, of your 50 M-Summicron or 90 M-Elmarit, and you are using them, say, on a Nikon Z camera, you can now ooch the rear element away from the sensor (in exchange for a slightly longer exposure time).
56 DIN
Newbie
the start for this adapter ralley came with Sony Nex cameras. Samsung came with similiare NX cameras, but didn´t stay in business. After purchasing one of the first Sonys, my stock of any manual lens, projector lens, etc., raised dramatically. I got some nice pictures, a lot of technical experience, but it was not photographing, it was feature testing. Nevertheless I am happy (?) today to have the opportunity to use any lens on my cameras. Using Nikon Z, urged me to buy a new set of adaptors and forced me to buy the Nikon LTM series - I wish, this golden age would never have started (see happy 
).
).
Canon made rangefinder cameras before World War II. Nikon made RF coupled lenses for them. There was collaboration between Japan and Germany before the war. German optical engineers moved to Japan before the war broke out, and assisted in growing the industry. After the war- the emphasis was on producing high-price merchandise that was labor-intensive and required small amounts of raw material. The Contax mount has some advantages over the coupling of the Leica mount: the fixed rotation of the lens provides the coupling. The lens latches into position.
Darthfeeble
But you can call me Steve
The golden age so far has me with a Canon LTM lens mounted to a Voigtlander M adapter connected to an M to Hasselblad X adapter mounted on a 907X. All that and it works perfectly. Amazing.
wlewisiii
Just another hotel clerk
I'm expecting to take full advantage of this by buying a used Nikon Z5 and adapters for all the types of lenses I own for SLRs & RFs for less than the cost of a new Z5
Nikon F/AI->Z
Leica M->Z
M42->Z
CanonFD->Z
The only one that will throw an expensive monkey wrench in there is the Amedo adapter for my Nikon S lenses but that's still well worth it.
By high summer I could have my 1937 collapsible Zeiss 50/2 Sonnar adjusted to Nikon standard on an Amedo adapter on a M-Z adapter on a Z 5 and expect utterly perfect monochrome images.
Nikon F/AI->Z
Leica M->Z
M42->Z
CanonFD->Z
The only one that will throw an expensive monkey wrench in there is the Amedo adapter for my Nikon S lenses but that's still well worth it.
By high summer I could have my 1937 collapsible Zeiss 50/2 Sonnar adjusted to Nikon standard on an Amedo adapter on a M-Z adapter on a Z 5 and expect utterly perfect monochrome images.
Darthfeeble
But you can call me Steve
I did lie a bit, the m lenses do vignette a bit, but it's correctable.
GMOG
Established
Funny - I often add a bit of vignette to images in the digital darkroom because it contributes to separating the subject from the background. 😄
Ko.Fe.
Lenses 35/21 Gears 46/20
If you have multiple bayonets mirrorless cameras get one M mount adapter for each bayonet. Then you could buy any manual focus lens with M mount adapter which will allows to mount at all cameras you have.
pgk
Well-known
FWIW I have an 1865 stereo lens which has a screw thread only marginally different to LTM (same diameter slightly greater number to threads per inch) and it will screw into to an LTM adapter by about 1.5 turns which is ample to fit it to a bellows and use it. Results are surprisingly good:
Darthfeeble
But you can call me Steve
I even lied about the fixable, the vignette is very black and can only be faded or if someone is good in PS I guess it can be fixed with AI. I covered it with the vignette tool and it looked a little too much to me.
cboy
Well-known
interchangability has its caveats as the tolerances to the flange back distance can vary between third party adapters. The fit / finish and machining of an adapter has a lot to do with whether or itll be an enjoyable experience. Sorry to say from my experience most MIC adapter havent lived up to expectation. Id suggest to get quality adapters. i recommend is rayqual, novofex & metabones when it comes to 'dumb' adapters
Peak adaptation: autofocus your lens built in the 1930s!
Or how about autofocus your adapted rangefinder lens to 0.3m instead of its native 1m close focus limit ?
Truly the Golden Age.
Or how about autofocus your adapted rangefinder lens to 0.3m instead of its native 1m close focus limit ?
Truly the Golden Age.