johnvanr wrote:
Just realized that much of this discussion focuses on Voigtlander lenses. Canon’s RF mount isn’t closed to manual focus lenses, like the VL ones. I’ve never seen the reason that VL limits its choices for the RF mount, while offering a wide range of lenses for the E and Z mounts.
Voigtländer does actually support RF, just not with the same depth as E or Z.
From what’s been documented, RF isn’t technically closed to manual lenses, since purely mechanical designs still work fine. The difference seems to be more about ecosystem strategy and market size than compatibility.
Sony E and Nikon Z have ended up being more attractive platforms for Cosina to expand their Voigtländer lineup, likely because the manual-focus audience is larger there and third-party support is more predictable long-term.
In my case, I don’t really have the time or patience to wait for that depth to develop on RF, so I’m working with what’s already well-supported today.
pgrillone wrote:
Voigtländer does actually support RF, just not with the same depth as E or Z.
From what’s been documented, RF isn’t technically closed to manual lenses, since purely mechanical designs still work fine. The difference seems to be more about ecosystem strategy and market size than compatibility.
Sony E and Nikon Z have ended up being more attractive platforms for Cosina to expand their Voigtländer lineup, likely because the manual-focus audience is larger there and third-party support is more predictable long-term.
In my case, I don’t really have the time or patience to wait for that depth to develop on RF, so I’m working with what’s already well-supported today....Show more →
Yes, but I still don’t get it. Canon and Nikon have better MF functions for lenses with the right connections than Sony, and Canon is undoubtedly bigger than Nikon in the mirrorless world, so why is that mount not as attractive for Cosina?
johnvanr wrote:
Yes, but I still don’t get it. Canon and Nikon have better MF functions for lenses with the right connections than Sony, and Canon is undoubtedly bigger than Nikon in the mirrorless world, so why is that mount not as attractive for Cosina?
I think Cosina is struggling with color shading with some Canon non-BSI sensors (including R6 series and lower end models) and they have warnings about color shading with certain Canon camera models for some of their lenses on the product pages. That seems to limit what lenses they will choose to do for RF mount. So far there are no WA lenses where this problem could be bigger, and also no APO-Lanthars. Also, their RF lenses don't seem to sell as well as E and Z in Japan at least.
I think with Z-mount Cosina benefits from lack of native Nikon lenses that would be a nice match for ZF from look and feel perspective.
Cosina does have a licensing agreement with Canon for RF-mount. It's not that RF would be open for manual focus lenses with electronic contacts.
johnvanr wrote:
Yes, but I still don’t get it. Canon and Nikon have better MF functions for lenses with the right connections than Sony, and Canon is undoubtedly bigger than Nikon in the mirrorless world, so why is that mount not as attractive for Cosina?
My guess would be licensing. Cosina gets full-compatibility with five-axis IBIS with all the mirrorless lenses they produce (though, in some cases, like with Fuji, that's camera-dependent). If Canon doesn't want to license them or Cosina doesn't see a profit with the lenses in RF or they have some other agreement stopping them, we'll likely never know.
freaklikeme wrote:
My guess would be licensing. Cosina gets full-compatibility with five-axis IBIS with all the mirrorless lenses they produce (though, in some cases, like with Fuji, that's camera-dependent). If Canon doesn't want to license them or Cosina doesn't see a profit with the lenses in RF or they have some other agreement stopping them, we'll likely never know.
Cosina have the distance encoder only on their E-mount and X-mount lenses, and 5-axis IBIS can be available only when there's distance information available. They don't have 5-axis IBIS available with their RF and Z-mount lenses. (They advertise 3-axis for those systems.)
Cosina did advertise that they had acquired a mount licensing agreement with Canon before they brought out their first RF-mount lens (50/1), and Canon also referred to that agreement when they later talked about RF mount not being entirely closed. I'm not sure if the licensing agreement requires lens-by-lens approval though.
I saw on some internet site that some Japanese person had asked Cosina about why Septon 40/2 wasn't announced for RF mount at CP+ and the answer was referring to sensor compatibility issues (which I think likely means that the lens would have had too noticeable color shading issues on R6 series etc). On the other hand, Cosina announced 35/1.4 for RF mount, so possibly that lens' optical design is somehow more forgiving.
Cosina have this warning on the product pages of their 40/1.2 and 50/1, but no such warning on product pages of 75/1.5 and 75/1.8:
*1 Due to the optical characteristics of the lens, magenta cast may occur in the peripheral areas of the image when using the EOS R, RP, and R6 depending on the shooting conditions.
Since R6 series are the biggest selling Canon RF models at least in Japan market, I think this is a major constraint with their RF lenses...
Juha Kannisto wrote:
Cosina have the distance encoder only on their E-mount and X-mount lenses, and 5-axis IBIS can be available only when there's distance information available. They don't have 5-axis IBIS available with their RF and Z-mount lenses. (They advertise 3-axis for those systems.)
Cosina did advertise that they had acquired a mount licensing agreement with Canon before they brought out their first RF-mount lens (50/1), and Canon also referred to that agreement when they later talked about RF mount not being entirely closed. I'm not sure if the licensing agreement requires lens-by-lens approval though.
I saw on some internet site that some Japanese person had asked Cosina about why Septon 40/2 wasn't announced for RF mount at CP+ and the answer was referring to sensor compatibility issues (which I think likely means that the lens would have had too noticeable color shading issues on R6 series etc). On the other hand, Cosina announced 35/1.4 for RF mount, so possibly that lens' optical design is somehow more forgiving.
Cosina have this warning on the product pages of their 40/1.2 and 50/1, but no such warning on product pages of 75/1.5 and 75/1.8:
*1 Due to the optical characteristics of the lens, magenta cast may occur in the peripheral areas of the image when using the EOS R, RP, and R6 depending on the shooting conditions.
Since R6 series are the biggest selling Canon RF models at least in Japan market, I think this is a major constraint with their RF lenses......Show more →
A wealth of good stuff, Juha. I had no idea about the RF and Z mounts not getting five axis. I wonder if you can get it on Nikon using a smart adapter and E mount lens.
freaklikeme wrote:
A wealth of good stuff, Juha. I had no idea about the RF and Z mounts not getting five axis. I wonder if you can get it on Nikon using a smart adapter and E mount lens.
At least the distance info should be present in the EXIF data provided by the E-mount lens, so if the smart adapter can keep the data intact, theoretically it should seem possible to deliver the distance info via E-mount lens + smart adapter, but I have no idea if there are some unique constraints depending on each system / adapter etc. The lens optical correction metadata with E-mount lenses adapted to Z doesn't seem to be supported via smart adapters (for some reason) based on what I've read...
