Site Sponsors
Results 1 to 4 of 4

Thread: Leica m-mount '6-bit'-encoded lenses?

  1. #1
    New Member
    Join Date
    May 2015
    Posts
    16
    Post Thanks / Like

    Leica m-mount '6-bit'-encoded lenses?


    I'm a bit confused by these.. Apparently this encoding system sends some lens info to the camera, but...
    1. What info? Lens type? Focal length? F-stop?
    2. To only Leica bodies? Or does this quite-expensive Leica-brand adapter...
    https://www.bhphotovideo.com/c/produ...r_leica_t.html
    ...transmit this data to 'all' L-mount bodies and, more specifically, to the Lumix S1R?

    After reading lots about the Tri-Elmar 16-18-21 ('WATE' or 'WA-TE') including Lens Rentals' tests on a Sony a7RII...
    https://www.lensrentals.com/blog/201...series-bodies/
    ...I'm seriously considering the WATE as my only UWA lens*.

    Asked another way, does buying the Leica adapter instead of another dumb-adapter do anything good but add to Leica's riches?
    .

    * Have already tested and rejected two Canon 16-35s (F4 and F2.8-II) and the TS-E-24, a Leica 16-35/2.8-4 L-mount, and a Zeiss 18mm/2.8 Milvus (EF).. My current UWA keeper is the new Sigma 14-24 L-mount Art.
    .

  2. #2
    Super Duper
    Senior Member
    Godfrey's Avatar
    Join Date
    Jan 2009
    Location
    Near San Jose, California
    Posts
    8,747
    Post Thanks / Like

    Re: Leica m-mount '6-bit'-encoded lenses?

    Quote Originally Posted by jeffreybehr View Post
    I'm a bit confused by these.. Apparently this encoding system sends some lens info to the camera, but...
    1. What info? Lens type? Focal length? F-stop?
    2. To only Leica bodies? Or does this quite-expensive Leica-brand adapter...
    https://www.bhphotovideo.com/c/produ...r_leica_t.html
    ...transmit this data to 'all' L-mount bodies and, more specifically, to the Lumix S1R?

    After reading lots about the Tri-Elmar 16-18-21 ('WATE' or 'WA-TE') including Lens Rentals' tests on a Sony a7RII...
    https://www.lensrentals.com/blog/201...series-bodies/
    ...I'm seriously considering the WATE as my only UWA lens*.

    Asked another way, does buying the Leica adapter instead of another dumb-adapter do anything good but add to Leica's riches?
    .

    * Have already tested and rejected two Canon 16-35s (F4 and F2.8-II) and the TS-E-24, a Leica 16-35/2.8-4 L-mount, and a Zeiss 18mm/2.8 Milvus (EF).. My current UWA keeper is the new Sigma 14-24 L-mount Art.
    The Leica six-bit codes for M lenses tell the camera body (Leica M series digital bodies, the SL, and the CL/T/TL/TL2 series) what lens is in use, adding info to the EXIF specifying the lens, its focal length, and its maximum aperture. The in-camera imaging system then knows what lens profile to apply to the image captured with that code to optimize the lens rendering for whichever Leica body is being used with the lens.

    The actual f/stop being used for a specific exposure can only be estimated since M lenses have no connection to the camera body that will readout the physical aperture ring setting and make it available to the body.

    I have no idea whether the M Adapter T/L transmits the data to a non-Leica L-mount body, or whether said bodies have any Leica lens profiles embedded in them. Others may know those details, but I don't own any non-Leica L-mount bodies. (Frankly, I haven't even seen one yet.)

    The Tri-Elmar-M 16-18-21mm f/4 ASPH (aka WATE) is without a doubt one of the finest performing ultra wide zoom lenses around. I had one for some time and it's a terrific performer on both the M and SL cameras. That said, once I moved to the CL body with its smaller APS-C sensor, it wasn't wide enough for me and it fell out of use in my kit, so I sold it. (To replace it on the CL, I use the Voigtländer HyperWide 10mm f/5.6 ASPH, and it is a terrific performer too.)

    There are various reasons to use the Leica M Adapter T/L (they changed the name from M Adapter T to M Adapter L once the SL was released) instead of a third party adapter. First and foremost is that it is one of the best made adapters out there, with much more precise mount registration than most of the third party ones (so the focusing distance scale stays accurate). Second is that it is the only adapter that allows some convenience features (like the focus assist magnification control on the CL body to be done with the dial). And third is that it's the only adapter that allows the lens code to be properly, automatically transmitted to the body to populate the EXIF data correctly and automatically invoke the lens profiles (on Leica bodies for sure, others see above).

    Since I use M and R lenses on my CL exclusively, the M Adapter L is essentially always on the lens mounting flange (I use the R Adapter M stacked on it to mount my R lenses). When I had the SL body, it was similarly on the lens mounting flange any time I was using M or R lenses, which was most of the time.

    G
    Godfrey - GDGPhoto Flickr Stream
    Likes 1 Member(s) liked this post

  3. #3
    New Member
    Join Date
    May 2015
    Posts
    16
    Post Thanks / Like

    Re: Leica m-mount '6-bit'-encoded lenses?

    Godfrey, TYVM for your comprehensive reply.

    I've ordered the Leica adapter to be delivered tomorrow, Wednesday, and tomorrow I plan to travel two hours south to Tucson to retrieve a WATE I bought today. We'll see how this goes.

    I'll post pics soon; then all of us will know what an S1R and WATE look like together.
    Likes 1 Member(s) liked this post

  4. #4
    Senior Member
    Join Date
    Dec 2007
    Location
    Jerusalem, Israel
    Posts
    1,541
    Post Thanks / Like

    Re: Leica m-mount '6-bit'-encoded lenses?

    Godfrey describes two good reasons to use the Leica M to L adapter and the WATE (16-18-21) lens is very telecentric, so that it should work without problems on the Panasonic image chips with their somewhat thicker cover glass.* Greater precision is a good reason to go with the Leica adapter. But the second reason cited, the profile corrections provided by Leica on its L-mount cameras, don't seem to be supported yet by Panasonic, beyond putting the correct information into the EXIF, and passing the correct focal length to the image stabilizer. That information occupies large tables in Leica's camera firmware, at least when it was last user-readable, and it may not have been included in the contractual agreements that underly the L-Mount Consortium.

    The WATE should be ideal for seeing the Sonoran desert, and with 48 MPx, there will be a lot to see.

    *Jono Slack loves the WATE and showed some pictures taken with it in his review of the S1.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •