Third-party lenses for Leica may be good and affordable. But they can’t communicate with your camera. This is a disadvantage in more ways than one. But the problem can be solved. Here, I show some solutions for owners or prospective buyers of Zeiss, Voigtländer, Thypoch, 7Artisans, TTArtisans, Laowa and other third-party lenses.
As Macfilos readers, who have followed the M Files series so far, know: This series is mainly about third-party lenses for Leica. Many of them offer excellent value for money, thus making rangefinder photography more accessible. This is an idea that our series strongly supports.
However, there are some restrictions with these non-Leica lenses when it comes to image processing (both in-camera and on the computer) and the integrity of your image database. This article gives advice on how to overcome them. Some workarounds are also helpful for film photographers who have scans of their negatives (or slides).
Leica lens, Leica camera – a good connection
To start with the one big question. Do original Leica M lenses make the best fit with a digital Leica M camera? Arguably yes. Leica designed newer lenses with the high-resolving sensors in mind, Peter Karbe of Leica confirms. And thanks to Leica’s exclusive 6-bit coding, the camera knows which lens is attached, and can apply correction profiles. Purists may be a bit doubtful. But I can tell from long experience that the tweaks are moderate in most cases, but generally effective. Images taken with third-party lenses for Leica M will not receive this kind of treatment. Because, as mentioned, only Leica’s own M-Mount lenses have 6-bit coding. All lenses without this feature will be “unknown” in the first instance.
How you can tell your camera which lens is attached?
Both Leica M and SL cameras have a function to select manually the profile for an attached lens. This is mainly meant for older Leica M-Mount lenses which have no 6-bit coding. But it is, of course, also possible to assign such a profile to a third-party lens – as long as the profile ensures an improvement of image quality.
For example, people recommend using the profile of the Summicron 50 (version III, Leica article number 11817) for the Konica M-Hexanon 50/2. For Leica SL (version 2 and 3) users, this function is even more important. That’s because in-body image stabilization (IBIS) only works when the camera knows the focal length of the attached lens. No problem with modern, electronically coupled, AF lenses. Not so easy with older ones, and tricky with one of the many third-party lenses for Leica.
What is the 6-bit code, and how does it work?
Leica’s 6-bit code is probably best described as a very basic barcode. It consists of six fields at defined places on the lens bayonet mount. These fields can be either white or black. This way, 2x2x2x2x2 or 2^6 combinations are possible. As a table by Akara labs shows, recent and historical Leica lenses only use around only two thirds of the 64 available codes. So, there are still plenty of codes available for other lenses.
An opto-electronic reader in digital Leica M-Mount cameras can read this sequence and translate the information to the assigned lens. This is necessary as there is no electronic link between lens and camera in the M system (who would have thought of that, back in 1954?). For example, the 6-bit code “black-white-white-white-white-black” stands for the Summicron 50, versions IV and V. The camera will use this information for the mentioned correction algorithms and for adding the lens info into the EXIF files of the image.
Which lenses have 6-bit coding, and can it be added later?
All newer Leica M lenses come with 6-bit coding. To make it durable, Leica has six small pouches milled into the lens mount. They then fill these small recesses with either black or white paint. This ensures that rotation of the lens in the bayonet will not rub off the code. Leica’s customer care department can code older lenses. I had a MATE (Tri-Elmar 28-35-50) coded in March 2022. It cost me €261.80, VAT included, with a cleaning service for the lens. I found this pricing very fair.
Third-party lenses for Leica can be equipped with the code by a few workshops. I know that Skyllanney in Scotland offers this service, and having experienced their level of quality, I am sure they do a wonderful job. Unfortunately, they are no longer serving international customers due to customs bureaucracy. Another address that is frequently mentioned are Will van Manen and Cathy Kuiper in the Netherlands. I have no experience with them.
Why is the 6-bit coding helpful also on third-party lenses for Leica?
Third-party lenses for Leica are obviously coming without 6-bit coding. And Leica M cameras have no embedded software-based correction profiles for lenses from other makers. This is understandable, why should Leica help the competition and give away a unique selling proposition for their own lenses? And, I think, only excellent knowledge of a lens, ideally through in-house development, results in a perfect correction profile.
However, Leica’s profiles can be a good approximation to get the best out of third-party lenses for Leica. Some of them are similar or have similar characteristics to Leica lenses. Zeiss even issued a chart that actually shows which profile is recommendable for which ZM lens. In many instances, the notorious “Italian flag” problem, also called colour drift, can be greatly reduced. And there is another reason for attaching the 6-bit code to Voigtländer, Zeiss, and other lenses. It will help you to keep track of your image details. More on this later.
What if I use third-party lenses for Leica on cameras of other brands?
If you only shoot film, or if you are using third-party lenses for Leica on another digital camera than a Leica M or SL model, there is no benefit in a 6-bit code. Only the original Leica M-Mount to L-Mount adapter is able to read the lens information and to transfer it to an SL camera. Even with other L-Mount cameras such as the Panasonic S5, it will not work. The Novoflex and other adapters for M-Mount to Nikon Z, Sony E or Canon RF will not support the data transfer anyway.
As I explained, 6-bit coding is something only a Leica camera can handle. If you are sure that you will never use M-mount lenses on a Leica M or Leica SL body, 6-bit coding makes no sense for you. If you are using a film or non-Leica camera, you can skip the following paragraphs and continue with my suggestions for getting the EXIF files right.
How does DIY coding of third-party lenses for Leica M work in practice?
There have been several methods suggested for do-it-yourself coding of lenses. I can warmly recommend the new lens encoder by Akara Labs that was featured in Jason’s Newsround a few weeks ago. It comes from England, and I received it within days of my order. The price of €21.95 seemed quite acceptable. In the end, it was €37.63 with shipping, import duties and DHL’s handling fee for a small envelope.
The content is great. The encoding template seems to be 3D printed to excellent standards. It has a notch that clicks into a standardized notch on the lens flange. Then you look up which code you want to use and fill the holes where the coding is supposed to show black. White coding is not necessary, the silver of the flange will be read as white by the camera. Akara Labs, however, also sells a kit with a black and a white pen.
I bought the pen separately and went for the recommended Uni Super Ink Marker PNA-125. This seems to be a very durable paint that will survive quite a few lens change actions. And if abrasion has taken away too much colour, you can carefully swipe the flange with a good cleaner and re-apply the colour. The pen is a 0.9mm tip, which seems pretty big for the small holes in the encoder, but it does work.
Instead of describing the procedure, I recommend Akara Lab’s video, which explains it all in a few minutes. After seeing it, you can start right away, it is all very easy.
Which code do I use for which lens?
Akara Lab’s instructions contain a suggestion on which code is sensible for many third-party lenses for Leica M-Mount. And it recommends: “If your lens is not listed, find the closest equivalent in focal length and widest aperture”. For example, the rather new Voigtländer 75/1.5 is not yet in the list. I tried the code 100011 (for the discontinued Summilux 75, black-white-white-white-black-black, always clockwise) with good success.
If you want to try different options before painting your lens, remember that you can manually select M lenses on your Leica. In case of the Voigtländer 75/1.5, you could also try 100100 (Apo-Summicron 75) or even 101101 (Summarit 75/2.5) or 010011 (Summarit 75/2.4). A perfect setup would include an evenly lit white surface (in order to control vignetting compensation) and a geometric pattern, ideally uniformly chequered, to control distortion.
What has 6-bit code to do with EXIF data?
If all went well, your Leica M or SL camera will record that an image with the Voigtländer 75/1.5 was “made with a Leica Summilux 75/1.4”. While the result of in-camera image correction might be convincing, the EXIF data, in which the name of the used lens is embedded, is false. Remember, if your third-party lens for Leica M is not coded at all, the field will remain entirely empty, which is not much better for sure. But if you are not keen on perfectly correct EXIF data, all is done for you at this stage.
In case you want or need the correct lens name in your EXIF data, there is another step to be made. Probably you own both the Leica Summicron 35 ASPH and the Voigtländer Ultron 35/2. Both use the same 6-bit code. This results that images that were made with either of the lenses appear in the same selection if you filter by lens in the metadata (for example, in Lightroom). If you have not written it down somewhere or your memory is not outstanding, you might no longer remember which of the two lenses was actually used after a few months or years.
How can I create or change EXIF data?
Now, the LensTagger plugin for Lightroom or another software for manipulating EXIF files comes into play. I described it extensively in this article, so I will just mention the steps: Select all images made with a particular lens, save the metadata, open LensTagger and create or use a lens profile for the actual lens, run it, reload the modified metadata and away you go. In this workflow, the “similar Leica lens” is just a placeholder.
And if you are not perfectly happy with the in-camera lens correction, you can disable it in Lightroom and apply one of the lens profiles provided by Adobe. Many third-party lenses for Leica M are in the library, among them most Zeiss ZM and Voigtländer VM lenses, but unfortunately none of the Konica, Minolta or other older M-Mount lenses that were featured in our M Files series. So far, profiles for the newer M-Mount lenses from China are also lacking, but maybe Adobe will add them at a later stage.
How important is to have an intact photo library?
At the end of the process I have described, you have a perfectly intact photo library with the best possible lens corrections. It seems to be a lot of work to reach this goal, and you might ask if your time is not better invested in going out and actually taking photos. I can’t answer this question for you. Using so many different lenses, also when reviewing them for you, I couldn’t maintain the overview without these steps (which cause less work than you think, once you are used to it).
Sure, “unknown lens” in my Lightroom catalogue is no problem for me in my leisurely shooting. If I have to take the responsibility for a published review, I need to keep track of things, though. And I love to store the information on the lens used for my scanned film photos as well. Instead of a scanner model name, I have my correct Ultron or Biogon or M-Hexanon or whatever else designation now in my photo library, just thanks to LensTagger.
Conclusion: Third-party lenses for Leica M on steroids
I have tried to explain a) what 6-bit coding for M-Mount lenses is; b) how it works; c) what it is good for; d) why it can be a good idea to give 6-bit coding to third-party lenses for Leica M and e) how you can use this code as placeholder for your actual lens and how you insert its name into your EXIF data. It’s rather technical, I know, but it is an important part of the answer to the old question of whether or not you should go for non-Leica lenses.
In our M Files project, we want to show options for a less exclusive kind of rangefinder photography. Many third-party lenses for Leica M are very affordable, and one of their biggest drawbacks is that they can’t communicate with a digital Leica camera. Now you have seen how you can overcome this with limited effort. The Akara Labs encoder and LensTagger together are a real improvement. They give you, so to speak, third-party lenses for Leica M on steroids.
What do you think?
Is 6-bit coding crucial for your workflow? Have you ever tried to play with all the lens profile options? Or are you a brand purist anyway and will never try third-party lenses for Leica? Or have you another solution for the described problem or an interesting technology for adding 6-bit coding to M-Mount lenses? Leave your thoughts and experiences in the comments section!
The M Files: Get in-depth knowledge of M-Mount lenses, cameras, and compatible accessories
The M Files is an ongoing project on Macfilos that focuses on photographic equipment with or for Leica M-Mount, made by companies apart from Leica or which are otherwise not part of Leica’s M system. It follows a more or less encyclopaedic approach without being scientific. The focus is always on the real-life use and usability of cameras, lenses and other items. Products covered by The M Files include cameras, lenses, viewfinders, light meters and more. Brands on the growing list include Contax, Konica, Minolta, Rollei, Voigtländer and Zeiss. Click here for the M Files Navigator, which gives you easy access to all articles and reviews by product type and brand.
Die M-Files: M-Mount-Objektive, -Kameras und passendes Zubehör jenseits von Leica M
Die M-Files sind ein Langzeit-Projekt, das sich auf Foto-Ausrüstungsteile mit oder für Leica M-Bajonett konzentriert, die von anderen Firmen als Leica hergestellt wurden oder die nicht zum M-System von Leica gehören. Es verfolgt einen mehr oder weniger enzyklopädischen Ansatz, ohne wissenschaftlich zu sein. Der Schwerpunkt liegt immer auf der praktischen Nutzung von Kameras, Objektiven und anderen Produkten. Zu den in den M-Files besprochenen Produkten gehören Kameras, Objektive, Sucher, Belichtungsmesser und mehr. Einige der Marken auf der wachsenden Liste sind Contax, Konica, Minolta, Rollei, Voigtländer und Zeiss. In deutscher Sprache erscheinen die Inhalte auf www.messsucherwelt.com.
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Thanks to everyone…
… for commenting and adding to the article. I can‘t answer to all details. Stephen, to most obvious correction is vignetting control (easy to achieve directly in Lightroom as well) and reduction of colour drift at the left and red margins of an image with wide-angle lenses, especially under 28mm. This one is less easy to get rid of in post-processing. Third is, as David B. is helpfully pointing out, flatting the field. With optically good lenses, is is a minor issue however.
The other question is if changing the mount ring helps. There are third-party solutions, many of which are astonishingly inexpensive. I never tried any of them so I can‘t comment on it. What I can say however is that every manufacturer has their own design of how the bayonet ring is fixed to the lens (number, placement and character of the screws). Leica has a standard for this of course, als Voightländer, but historical Minolta, Konica or Kobalux lenses are all special in their own ways.
I hope some of the questions are answered. Being back in civilisation, I am happy to reply to upcoming comments, but it might take a day or two.
JP
I for one am very excited about this little adapter. I almost never remember to change lens profiles in camera. Based on Macfilos report of this little guy a short time ago, I ordered one. It should be here in a few days and I am stoked to give it a try!
I don’t care too much about exif data or lightroom, just the out of camera image qualty. I do wonder just how much an improvement I would see if I had Leica add the codes to my M lenses for use on my SL2s I do little image correction in post.
What does “the tweaks are moderate but generally effective” mean?
Could you be more specific? I own Leica M lenses without coding in 35,50, 90 and 135 focal lengths. What advantages could I expect to see in terms of correction of actual image Quality? Does Leica specify this anywhere for each lens or do we just have to assume the coding software is doing something but we don’t know what until we try it?
Well, as J-P hasn’t replied yet, I think – in my experience, anyway – “the tweaks are moderate but generally effective” means that the vignetting of some lenses is reduced, and curvature is sometimes adjusted to render straight lines straighter.
The handy thing, for me, is that the EXIF data shows which lens was used, as in “was it the 50mm APO, or the 50mm retractable f2.8, or something completely different? ..old collapsible Summicron, old collapsible Hexamethadichloropumpiform, or old screw-fit Amotal Anastigmat?” ..daughter of Mr & Mrs Stigmat: she’s their daughter Ana.
J-P is on holiday, last heard of somewhere in the high Alps, and expecting no cellular connection. No doubt he will respond when he can.
David and Mike, thanks for the replies. I might finally get around to getting my lenses coded this year. It might be worthwhile anyway to make them compatible with any future and presently unknown future innovations in the Leica system.Also I need to visit the Leica store anyway since I’ve got my eyes on a pair of Trinovids or Ultravids for travel.
Hope J-P is having a good time. No cellular connection-holidays are the best kind.
.
This article looks so familiar, as if it’s been posted a few years ago – must be déjà vu, all over again.
I asked Leica to ‘code’ a few lenses for me a while ago ..I can’t remember quite what they were: a great 90mm f2.8, I think, and a few wide-angles. When I queried the price (..I’d previously asked Malcolm Taylor to do it, but that was also going to be expensive, and with a six-month wait..) they explained that the bayonet is taken off the lens, and a new bayonet – with pre-cut slots for the coding – is added.
That stops swarf (steel dust) getting into the lens mechanism, which would likely happen if the lens was clamped to a bench and then drilled to take the ‘code’ paint panels. Seemed reasonable, so I had it done. (And a bit faster than Malcolm would have done it.)
I’ve tried coding other lenses myself (..I have a chart of the relevant codes for all the different Leica lenses..) but the paint, or felt-tip pen, smears and wears off after a while. Stephen Gandy’s ‘Cameraquest’ site recommends – i.e; he sells – Rayqual ‘Type III’ screw-fit-to-bayonet adapters – for old Leica lenses – which DO have a recessed segment into which you can paint your own coding without it rubbing off. But that’s to adapt screw-mount lenses to M-mount and to ‘tell’ the camera – via coding – which lens you’re using. But – gasp! – they’re $79 each!
Meanwhile on eBay similar ones cost £8.99 and upwards ..and with notches for coding from £9.40 – which magically becomes £11.28, but maybe that includes postage from China.
I bought some cheapo ones some years back; work perfectly, and the coding never wears off, because it’s RECESSED, for about £5 each! ..And despite Stephen Gandy’s warnings about cheap adaptors, they’ve always worked perfectly!
But replacing the stainless steel mount (..you can’t drill into it; I’ve tried ..or maybe it’s just that I can’t drill into one!..) of native M-mount lenses is another matter altogether. You need pre-chiselled cutouts to take the coding paint, and you need the screw holes in the new, ‘code-able’ mount(s) to match perfectly the positions of the screw holes in your original uncoded lens mounts ..and those positions, and number of mounting screws, do differ widely between different lenses!
(Ah, looking at a random lens I’ve just picked up, I see that my Elmarit-M 21mm f2.8 lens of 1997 (that’s before coding was introduced) to 2011 (after coding was introduced with the M8) (white-black-black-white-white-white) IS coded ..but I can’t remember if it came like that, or if it was one of the lenses which I sent to Leica to have it done. [Date details from Frank Dabba Smith’s & David Slater’s little red ‘Leica Pocket Book’, version 9].)
Mounts with recessed space for 6-bit coding Leica lenses are available on eBay from $39, plus postage, from the USA, and replaceable mounts for coding a whole range of other (Cosina/Voigtländer, Zeiss, etc) lenses are also available if you look for ‘6-bit flange adapter ring’, or similar, starting at about $15.50 plus $4.50 postage from China. But be sure to count the numbers, and positions, of screws on your present – uncoded – lens mount before ordering ..otherwise the new replacement flange/mount will never fit!
It’s important, too, to buy the adapter for the specific focal length, otherwise the wrong frame lines may appear in your M viewfinder! ..if you’re going to use such adapted lens(es) with an M.
Coding makes all the difference for reducing vignetting, and applying some in-camera lens corrections. I’m all for adaptors, and for lens coding, despite detractors saying “nah; adaptors don’t fit properly, they’ve a sloppy fit, you can never focus properly..” etc. Makes using old, and un-coded, lenses a breeze!
Thanks for posting about your experience. It does seem expensive if you have many M lenses in your collection. I don’t much like the DIY marker pen options and would want Leica to do it. The fact that they take the bayonet off the lens and replace it with a new one seems to make sense.
One of the best things about the SL2 when it came out was that you could use a third-party M lens and by mimicking it to be an M lens with the built-in lens profiles you could also enable stabilisation.
I then also found this feature to be present in the GFX 100S similarly with, third-party lenses including M lenses with an adapter.