Leica uses paint marks to enforce 6 bit encoding to identify a lens, Leica, to a camera, Leica. Aftermarket LTM > M adapters can be bought with the ability to be painted for the same effect. Select the closest Leica lens to what you have and code it as such. That way the camera has a record of what it has been told you are shooting. We know this.
Pixii eschews 6 bit encoding. Patent protected by Leica? Or just not that valuable? I am assuming it only affects JPEG files. Any help here?
While on the adapting flange and bayonet mount I see Pixii identifies lenses by focal length through a software selection. Leica uses identifiers on the bayonet mount. Patent protected by Leica?
The 6-bit coding affects both raw and JPEG captures by nominating a Leica supplied lens profile. The profile's effects/corrections are 'baked into' Leica raw files as well as applied to the in-camera JPEG rendered files.
Leica's notion of lens profiles and corrections differs from other manufacturers. Because Leica has been producing lenses for many years, their notion isn't to do absolute rendering corrections to solve residual rectilinear aberrations and various other issues; what they do with the lens profiles is a serious attempt to preserve the original design intent and rendering of Leica lenses for their original application. So Leica R lens profiles attempt to make Leica R lenses look like they always did on film in a Leica R camera, etc.
Whether you want this, or not ... well, it's what the profiles are there for. I've seen nothing that indicates they degrade any lens performance at all, and I've seen plenty (in use on Leica M digital cameras) that indicate they enhance and preserve lens performance.
The effects of lens profiles are MUCH more marked on FF format sensors, since many of the aberrations of older lenses designed for film used on a digital sensor only affect the periphery of the imaging area. Most of that area is missing in an APS-C sensor with the result that the differences between profiled and non-profiled captures are hard to tell apart. Modern lenses (designed since the middle '00s) were designed and corrected for both film AND digital sensors so the lens profiles for them have a different purpose.
The M's mechanical frame line selection mechanism is genius and excellent, and probably adds 50-60% to the cost of the M rangefinder/viewfinder mechanisms due to the precision that it has to operate with to be consistent and successful. My opinion is that Pixii SAS, like most other manufacturers that have adopted the Leica M-mount to gain access to the excellent existing lens base (like Cosina-Voigtländer, for instance) uses manual mechanical or manual software switched frame line selection to save a bunch on cost of manufacture and lower the inspection/quality assurance costs.
(note: I cannot recall for sure whether the modern Zeiss Ikon (manufactured by Cosina) or the Konica RF cameras that used M-mount lenses supported the mechanical auto frame line selection mechanisms..)
Patents give a limited term of exclusivity to an invention, and the M's auto frame line mechanism was first released with the M3 in 1954. I don't know for sure what the patent time limits are, but they're surely not more than 50 years at the maximum. The time of 17 years sticks in my head for some reason, but I am not certain.
🙂
G
— addenda: on the subject of patent time duration
From
STOPfakes.gov:
"A U.S. utility patent, explained above, is generally granted for 20 years from the date the patent application is filed; however, periodic fees are required to maintain the enforceability of the patent. U.S. design patents resulting from applications filed on or after May 13, 2015 have a 15 year term from the date of grant; however, patents issued from design applications filed before May 13, 2015 have a 14 year term from the date of grant.."
So a patent filed on the mechanical auto frame line selection mechanism in 1954 would have run out by about 1969 at the latest.
