Sigma officially launches the RF 18-50mm f/2.8 DC DN Contemporary

This isn't the same as EF versus EF-S, which were different lens mounts (EF-S lens wouldn't physically fit onto a full frame EF camera without modification). And, as I recall, none of the third parties who made crop EF DSLR lenses (including Sigma) called them EF-S. But attentive buyers knew.
I do not think Sigma really made lenses for the EF-S mount.
I think they were EF lenses with a smaller image circle but I could be wrong.
 
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No, per the press release, Sigma is calling it the "SIGMA 18-50mm F2.8 DC DN |Contemporary for the Canon RF Mount System."

The CR headline calls it the "RF 18-50mm f/2.8 DC DN Contemporary", but that's not from Sigma.
Yes, companies can't use RF in the name unless it is preceded by the word "for".
Since there is no such thing as an RF-S mount, using that would not make sense.
 
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No, per the press release, Sigma is calling it the "SIGMA 18-50mm F2.8 DC DN |Contemporary for the Canon RF Mount System."

The CR headline calls it the "RF 18-50mm f/2.8 DC DN Contemporary", but that's not from Sigma.
Thanks for pointing out this very significant distinction, which means my discussion-point was going down a blind alley!

I see, in the article itself, it is referred to as the "Sigma...", not "Sigma RF...", but the headline certainly misled me.

So, :mad::mad::mad::mad::mad: to me for falling into this trap, but, perhaps, a little :mad: to the headline-writers, too?
 
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Thanks for pointing out this very significant distinction, which means my discussion-point was going down a blind alley!

I see, in the article itself, it is referred to as the "Sigma...", not "Sigma RF...", but the headline certainly misled me.

So, :mad::mad::mad::mad::mad: to me for falling into this trap, but, perhaps, a little :mad: to the headline-writers, too?
No worries, we all do it. I'm sure if you went into any camera shop and asked for the "Sigma RF 18-50", nobody will complain. They'd rather sell you a lens than call the trademark police.

But this is the internet, and it's our duty to nit-pick every last detail of what everybody says.
 
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This highlights what the photography industry is really missing: IP rating numbers, or a new scheme for equipment.

My iPhone has an IP rating of 68, but my camera? Crickets.
I think the problem has always been, you have a big hole on the front of an interchangeable lens camera. Most modern phones are sealed units. Not an insurmountable challenge to provide a rating, but there would be lots more caveats depending on lens etc.
 
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I watched this lens review from HK youtuber.
He said he didn't update his R8 firmware but R8 has this Sigma lens information. He guesses Canon got all Sigma lens information a long time ago. Just wait Canon make a green light.
The photo result is sharp from R8 also.
 
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I think the problem has always been, you have a big hole on the front of an interchangeable lens camera. Most modern phones are sealed units. Not an insurmountable challenge to provide a rating, but there would be lots more caveats depending on lens etc.
Remember the Nikon 1 AW1? I was quite tempted by that system. It was rated IP68 (with two specific lenses, so you're right about caveats). The Oly OM-1 is rated as IP53.
 
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I watched this lens review from HK youtuber.
He said he didn't update his R8 firmware but R8 has this Sigma lens information. He guesses Canon got all Sigma lens information a long time ago. Just wait Canon make a green light.
The photo result is sharp from R8 also.
On EF-M and RF the lens itself contains the information, so the body doesn’t need to have any information in its firmware, it will get transferred from the lens.
 
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On EF-M and RF the lens itself contains the information, so the body doesn’t need to have any information in its firmware, it will get transferred from the lens.
I'm pretty sure that the EF system works the same way. The database definition would be in the camera and the lens would provide the information to fill the record to the body. Otherwise, every time you introduce a new lens, every camera to use that lens would have to have its firmware updated. The genius of the EF system is that the camera firmware itself seems to be extendable, with new features being added. For example, I don't think in-lens IS was part of the original firmware.
 
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There's definitely something lens-specific in the camera firmware. Canon frequently releases new body firmware with new lenses, citing support for the lens in the release notes.

When I first got the RF-S 10-18 in December, my R7 gave me a warning that it wasn't supported in the current firmware. Canon released a firmware update a couple of days later (v1.4) that added it.
 
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I think the problem has always been, you have a big hole on the front of an interchangeable lens camera. Most modern phones are sealed units. Not an insurmountable challenge to provide a rating, but there would be lots more caveats depending on lens etc.

Granted there are different design considerations that need to be taken into consideration when coming up with a rating scale and set of tests to verify the claims. If Canikony group want to use the IP scale or come up with something new, I don't care. Including if they have a list of caveats.

But they need to move on from making hand waving claims about weather resistant or whatever to something that is both measurable and testable. This might include, for example, having the plastic plug in the lens mount fitted, or with specific lenses.
 
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I'm pretty sure that the EF system works the same way. The database definition would be in the camera and the lens would provide the information to fill the record to the body.

This is correct and is one reason why Sigma and Tamron have difficulty: their lenses aren't in Canon's inbuilt list, so they have to pretend to be some other Canon lens (I think that's how it works.)
 
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I'm pretty sure that the EF system works the same way. The database definition would be in the camera and the lens would provide the information to fill the record to the body. Otherwise, every time you introduce a new lens, every camera to use that lens would have to have its firmware updated. The genius of the EF system is that the camera firmware itself seems to be extendable, with new features being added. For example, I don't think in-lens IS was part of the original firmware.
For EF lenses and early EF-M lenses you had the ‘lens registration utility’ where you could add 3 or 5 lenses to the body. Bodies like the 1dx3 had the complete EF database builtin, as do all the R bodies. I never used a 5 series, those might have had it builtin as well.

Late model Sigma EF(-M) lenses and the 2018 Canon super teles also had the profiles in the lens and would tell the body that.

I used the lens registration utility a lot with my 7D and M series, especially when I travelled with 4 ef-m lenses :)
 
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I watched this lens review from HK youtuber.
He said he didn't update his R8 firmware but R8 has this Sigma lens information. He guesses Canon got all Sigma lens information a long time ago.

Interesting. I wonder if there are other changes to RF that let the lens tell the camera what it is rather than just use a 2 digit code as I can't see why Canon would put 3rd party lens information in their firmware.
 
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This is correct and is one reason why Sigma and Tamron have difficulty: their lenses aren't in Canon's inbuilt list, so they have to pretend to be some other Canon lens (I think that's how it works.)
That’s correct for ‘old’ lenses like my sigma 150 macro, but newer ones, like the 105mm reported themselves and their corrections to the body, so no weird dark rings in the evf and jpegs.

The sigma ef-m lenses did the same, which is very helpful for things like vignette correction in video.

I have a script that corrects the exif on import for pics with the sigma 150, for the ef-m lenses it does the right thing already :)
 
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Interesting. I wonder if there are other changes to RF that let the lens tell the camera what it is rather than just use a 2 digit code as I can't see why Canon would put 3rd party lens information in their firmware.
Canon made a big thing about that when they introduced RF, with matching white papers.
What they didn’t tell you is that EF and EF-M could already do that, and the EF super teles they introduced at that event did do that as well.

Pretty much all the ‘new’ R stuff was already in the M50 :)
 
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