Why did Canon even bother with the RF mount?

Ruined

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Seems a weird choice .

* Folks report EF glass works spectacular with the RF > EF adapter on R5/R6. Therefore there is no doubt they could have created an EF mount R series.

* No one is buying the R5/R6/R3 if they want the slimmest camera. In fact, they had to beef up these cameras to closer to the size of an EF mount DSLR for people to get interested in canon FF mirrorless. So reducing the distance to the sensor doesn't buy them much.

* Most of the RF lenses have been different than - but not necessarily head and shoulders better than - similar EF equivalents. Many of them with improvements also had tradeoffs in cost, bokeh, functionality, or size. It's also possible many of these different lens formulas could have been made in EF mount if RF never happened

I don't get it. A single native mount (EF) that works great on the old and new cameras seems a much more powerful thing than a new mount that only works on new with gains that don't necessarily match the compatibility break. Was it just an attempt to tank 3rd party lens companies?
 
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neuroanatomist

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EF lenses are great. I have a 24-70/2.8 II. IS would be nice, but I wouldn’t replace my lens with a new one for IS alone. But that, plus a native mount for my new camera? Sure.

That, multiplied by a few million over the years to come.
 

Ruined

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Aug 22, 2013
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EF lenses are great. I have a 24-70/2.8 II. IS would be nice, but I wouldn’t replace my lens with a new one for IS alone. But that, plus a native mount for my new camera? Sure.

That, multiplied by a few million over the years to come.
Is 24-70 f/2.8 IS truly impossible on EF mount?

If R series came out with EF mount,.EF mount would have been the native mount on R
 

Joules

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In an environment where camera sales are dropping even on the high end, it makes sense to update the ecosystem to both make designing lenses more efficient (more economical) by adapting a mount that imposes fewer constraints (flange distance) and also motivates customers to replace parts of their existing lenses with the newer versions.

Only Canon knows how much money they're actually gaining by their strategy. But knowing how Canon did so far, my guess would be quite a lot.

There's no doubt that keeping EF and designing lenses that stick into the body was an alternative. But it would have introduced compromises that Canon seems to see as not worth maintaining the single mount. Especially since those lenses would have been incompatible with DSLR anyway, so what would be the point in having the EF mount?

Also, some lenses like the 7.1 and 11 aperture ones aren't backwards compatible with DSLR focus systems. So introducing those in EF mount could have added more confusion that Canon feels comfortable with.
 

neuroanatomist

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Is 24-70 f/2.8 IS truly impossible on EF mount?

If R series came out with EF mount,.EF mount would have been the native mount on R
Of course it’s not. There were patents for it. But releasing it only in an RF mount, or releasing a lens like the 28-70 f/2 only in RF mount, drives sales of both those lenses and the R bodies in which they mount.

You asked, “Why bother with an RF mount?” The answer is simple…more profit. You may wish they’d just stuck with the EF mount because it would be easier/cheaper/more convenient for you. Canon doesn’t really care about making things easier/cheaper/more convenient for their customers. They care about profit. That’s what for-profit companies are for, which is why they’re called for-profit.
 

dcm

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They also did it to create a new electrical connection that allows faster and more accurate autofocus with the new lenses. This may not have been possible with the old connections. The R bodies can handle both EF and RF electrical connections through the adapter. The may be other, future benefits with the RF mount that we haven’t seen yet.

Old bodies would not be able to take advantage of the new connections if they did it to the EF mount. Everyone would scream because the new lenses wouldn’t work well or at all on their old bodies. Didn’t Nikon do something like this with the F mount that created incompatibilities?
 
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privatebydesign

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I don't get it. A single native mount (EF) that works great on the old and new cameras seems a much more powerful thing than a new mount that only works on new with gains that don't necessarily match the compatibility break. Was it just an attempt to tank 3rd party lens companies?
Ok there are two major differences, flange distance and number of contacts.

The number of contacts means the 'legacy EF' lenses could never have had the functionality of the 'new EF' lenses, maybe that would be considered acceptable but Canon felt it was time to redesign the body to lens protocols, not just for the features available now like closed loop AF commands, which weren't possible with the older protocols, but things they haven't come out with yet like tilt/shift lens corrections and AF.

But the biggie is the flange distance, this allows completely new lens designs that we are starting to see now, 14mm full frame lenses with front filter mounts could not be made with the EF flange distance, they can be made with the RF flange distance, this allows the lenses to be smaller lighter and cheaper and easier to make.

If Canon had maintained the flange distance and split the EF lenses into old and new they would be behind the competition who can already benefit from the improved lens designs, ultimately it would have been a losing decision. The way they did it, make new lenses but have all the old ones fully compatible with a simple glassless adapter, seems like the best of all was to transition to me.
 

Czardoom

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A weird choice?

Look at all the folks buying these new lenses! If they kept the same mount, no new lens sales for all those that already have the same or similar lens in the EF mount.
Many folks have expressed an interest in smaller and lighter kits. While not all the RF lenses are lighter, some are substantially lighter and smaller. And every lens/camera combination is smaller due to the smaller flange distance. Plus, the R5 is smaller and lighter than the 5D IV, the R6 smaller and very slightly lighter than the 6D II, and don't forget how small and light the RP is.
And, yes, some of the more extreme lenses like the 14-35mm could not have been made the same in EF mount. And while the IQ of many of the newer lenses seems similar to the EF versions, some are noticeably better, especially wide open.
The new lenses have convinced some folks to switch to mirrorless and thus Canon sells new cameras that they would not have otherwise.

End result. Far more lens sales. Some additional camera sales.
The downside? Some DSLR owners may be disappointing that they can't use the new RF lenses. My guess is that there are not that many folks in this category, and Canon believes that they will eventually switch to mirrorless anyway since it now seems that DSLRs will not last much longer.
 
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john1970

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I think Canon realizes that mirrorless is the future. A lens mount that can exploit a narrower flange distance ,which is now possible without a mirror box, makes sense and allows for improved optical designs. The EF mount was started in 1987 and RF started in 2018 so the EF mount lasted 30 years. I would expect similar lifetime for the RF mount which is more that good enough for me.
 

dcm

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I think Canon realizes that mirrorless is the future. A lens mount that can exploit a narrower flange distance ,which is now possible without a mirror box, makes sense and allows for improved optical designs. The EF mount was started in 1987 and RF started in 2018 so the EF mount lasted 30 years. I would expect similar lifetime for the RF mount which is more that good enough for me.

Thirty years is a pretty good run for any technology. Looks like I’ll see at least three Canon mounts in my lifetime (FDn, EF, RF). FDn handled the transition to automatic exposure. EF handled the transition from film to digital. RF handles the transition to mirrorless. Maybe I’ll be around for the next one. I wonder what that will bring.
 

privatebydesign

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Thirty years is a pretty good run for any technology. Looks like I’ll see at least three Canon mounts in my lifetime (FDn, EF, RF). FDn handled the transition to automatic exposure. EF handled the transition from film to digital. RF handles the transition to mirrorless. Maybe I’ll be around for the next one. I wonder what that will bring.
Not really, FD made the transition to auto exposure from the FL. FL lenses could be mounted and used on FD bodies in stopped down metering mode though. FDn was just a modernization of the FD mount and didn’t add any functionality it just got rid of the FD chrome breech ring.

The EOS mount transitioned to AF not digital. There were several generations of cameras and nearly a decade between the introduction of EOS and general availability of digital cameras.

RF does indeed handle the transition to mirrorless.
 
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dcm

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Not really, FD made the transition to auto exposure from the FL. FL lenses could be mounted and used on FD bodies in stopped down metering mode though. FDn was just a modernization of the FD mount and didn’t add any functionality it just got rid of the FD chrome breech ring.

The EOS mount transitioned to AF not digital. There were several generations of cameras and nearly a decade between the introduction of EOS and general availability of digital cameras.

RF does indeed handle the transition to mirrorless.
Thanks for the corrections. I was thinking FL to FD, not sure why I used FDn other than that’s what all of my lenses were. I missed to FL to FD transition by a few years. EF was definitely for AF, but I like to think it also survived the film/digital transition as well even though it wasn’t really a mount issue. For that matter, mirrorless isn’t really a mount issue either, but it does give you an opportunity to improve the mount with some benefits.

For some perspective

1964 FL
1971 FD
1987 EF
2018 RF

Based on this trend (7, 16, 31 years), it could be a while before we see another mount. But I doubt it will be 60 years.
 
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Mt Spokane Photography

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The driver for RF is simple, profit. Canon had the opportunity to modernize the lens entirely, and the shorter flange back distance does provide benefits, but the main thing is that the design is locked up with many patents so there is no competition. That means big profits. Canon states it in their financial reports, RF lenses are big profit items. They are pushing R bodies in order to sell more lenses. I'm not sure if or when a fully compatible 3rd party RF lens will be available. So far, its said that the ones available are lenses with RF mount but EF electronics. That avoids the patent issues but it makes little sense to buy one since the EF version is more flexible and almost every R owner has a adapter (I have 4 of them)..
 
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Del Paso

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Of course it’s not. There were patents for it. But releasing it only in an RF mount, or releasing a lens like the 28-70 f/2 only in RF mount, drives sales of both those lenses and the R bodies in which they mount.

You asked, “Why bother with an RF mount?” The answer is simple…more profit. You may wish they’d just stuck with the EF mount because it would be easier/cheaper/more convenient for you. Canon doesn’t really care about making things easier/cheaper/more convenient for their customers. They care about profit. That’s what for-profit companies are for, which is why they’re called for-profit.
And I believed Canon was a charity.:cry:
I will jump ship, onto the soni raft !