Canon DSLR News

Opinion: Changing Canon camera lens mounts. How might the RF mount affect you?

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Keith over at Northlight Images, always a voice of reason has written an opinion piece about Canon’s new RF mount and how it might affect Canon going forward. He also addressed EOS M and the EF-M mount.

From Northlight Images:

We’re all doomed – or not

Already I’m seeing articles and comments about Canon’s move to the RF mount that are not even wrong in their level of their cluelessness about optics and the camera market(s) around the world.

The sky is not falling – perhaps some context and history will help.  In a few years all will be well, but probably better ;-)

Canon lens mounts – A brief history

Canon changes lens mounts and systems – some people are left behind, some move on.  With the new RF mount, there are many questions as to what it means for different categories of Canon camera user. This note aims to show a bit of historical context for the change – noting that past changes didn’t have the echo chamber of the internet to contend with…

I’ll mention some of the older lens mounts first, since many modern DSLR users may not even know this aspect of Canon’s lens history. Read the full article

crazyrunner33

EOS RP
Nov 4, 2011
306
125
I'm excited for the shorter flange distance. An adapter will not only keep my EF lenses in service, but will allow me to put my FD lenses back into action for old time sakes. This is not nearly as bad as the development of the EF mount that killed the FD lenses.
 

padam

EOS R
Aug 26, 2015
1,233
893
I think they will be keeping all the tele lenses as EF-mount, both the 70-200mm f/4 or f/2.8 will take some time to replace (maybe that will be the one to use DO elements to reduce the size and weight). So I really don't think they will change the 7D III from what it was. First they need to figure out sports autofocus in mirrorless anyways. As a first model I don't expect the EOS R to have that level of autofocusing ability (for instance the 5D IV DPAF is rated for lower EV and yet it doesn't work nearly as well as in 'normal' DSLR mode in low-light conditions)
 

CanonGrunt

C70
CR Pro
Jan 28, 2012
209
136
Well, there absolutely are adapter's to use FD lenses on EF mounts. Unfortunately they do add a glass element that is so so in quality, but they do exist. Just look over at B&H. I use FD lenses on my M5, witch thankfully the FD to EF-M mount adapters do not require extra glass, but I have had some pretty cool results mounting FD lenses to my c500. I assume that if one really wanted to make adapters for the EF-M lenses to work on RF and such, that they would also require an added glass element; not ideal.
 

Uneternal

EOS M6 Mark II
Jan 25, 2016
65
38
Who cares about if those 5 EF-M lenses are not adaptable to RF or vice versa.
If you switch from mirror to mirrorless you can keep all of your lenses, for me that's all that matters.
How knows, maybe EF-M is dead and Canon will come up with a new RF-M mount which is 100% compatible.
 

colorblinded

EOS M50
May 22, 2016
30
17
Who cares if EF-M lenses can't be mounted to RF? Why are we getting so hung up on that side of it? Canon never wanted you to mount EF-M on an EF mount, or an EF-S mount (nevermind the optical issues), they don't even want you using EF-S on EF.

All I want to know, if I eventually go down this path, is if I can use RF lenses on an EF-M body.
 

padam

EOS R
Aug 26, 2015
1,233
893
Who cares if EF-M lenses can't be mounted to RF?
All I want to know, if I eventually go down this path, is if I can use RF lenses on an EF-M body.

In a word, no.
The other direction can be argued similarly. Really, why buy the latest most expensive premium FF glass, pay even more for a fiddly adapter ring (if that would be possible, but it's not) and then put it on much cheaper and smaller camera (that probably won't get any bigger or get dual sd or a bigger battery) instead of EF (or EF-S) lenses that can be bought for less money and with lower cost adapters?
It can't be mounted, otherwise they could just skip the 32/1.4 EF-M in favour of the 35/1.8 RF with IS

There are cases where it makes sense to put FF glass on a crop body. This is not it.

It was annoying for some people not to be able to mount EF-S glass for the cropped 4k video, but that has been eliminated (and with optional filters added in for good measure)
 
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colorblinded

EOS M50
May 22, 2016
30
17
In a word, no.
The other direction can be argued similarly. Really, why buy the latest most expensive premium FF glass, pay even more for a fiddly adapter ring (if that would be possible, but it's not) and then put it on much cheaper and smaller camera instead of EF (or EF-S) lenses that can be bought for less money and with lower cost adapters?
It can't be mounted, otherwise they could just skip the 32/1.4 EF-M in favour of the 35/1.8 RF with IS

There are cases where it makes sense to put FF glass on a crop body. This is not it.

It was annoying for some people not to be able to mount EF-S glass for the cropped 4k video, but that's been eliminated (and with optional filters added in for good measure)
And thus, if you have both systems, there is never a way to make them play nice together. That was a potential perk, not a selling feature, but there are some lenses that are handy to be able to slap on an EF-M body. Canon is removing that option, and removing some other flexibility with the new mounts.

I don't see it as something you'd build a system around, but if you have both systems it's convenient to be able to bring some things over.
 
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padam

EOS R
Aug 26, 2015
1,233
893
And thus, if you have both systems, there is never a way to make them play nice together. That was a potential perk, not a selling feature, but there are some lenses that are handy to be able to slap on an EF-M body. Canon is removing that option, and removing some other flexibility with the new mounts.

I don't see it as something you'd build a system around, but if you have both systems it's convenient to be able to bring some things over.
Summing it up, it is pretty pointless to have both systems. But they do support you to get whatever APS-C EF camera you would like, and they may do one with an electronic viewfinder, job done.
And I can't see that much point anyway if you can't use the same batteries for instance. I think there will be an M5 Mark II later on, but the body will remain the same.

The limitation was not created now, not at all. It was created with the EF-M in the first place. But it also has advantages of being able to remain compact and light.
Looking at the bigger picture, it is not that big part of their overall market and even if it was compatible, I don't think people would buy these big heavy and expensive lenses for it (ok no price yet, but we'll see).
 
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amorse

EOS RP
Jan 26, 2017
797
1,084
www.instagram.com
Interesting read, but I still struggle in reading the tea leaves. The transition to EF from FD made sense in that it added a new functionality which one could argue created a significant shift in the industry. I'm really curious about what RF can do that EF couldn't - or maybe it is just the 24mm of flange?

It just seems odd to build the most robust lens lineup available only to loosen the grip on that advantage over the competition unless it is for the long-term good. Sure, EF is still functional using the adapter, but if users are willing to use an adapter to mount EF to RF, then it isn't as much of a reach to mount EF to E or Z.

Don't get me wrong, I'm on board for a compact full frame kit but I just don't understand the decision yet. Hopefully we'll know more tomorrow!
 
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padam

EOS R
Aug 26, 2015
1,233
893
The Z-mount has those golden contacts is a very different place so the adapter is fiddly to make, maybe that has had something to do with the Nikon F -> Sony E adapter actually making cameras non-functional. And we can add that the flange distance being so close, I really don't think of this as being feasible. This is nothing like mounting Nikon F lenses with manual mechanics on a Canon EF body.

Yes, you can use EF lenses on the E-mount if you need features that the Sony offers that's a given. Like FF 4k or higher framerates, built-in IS, dual cards slots (for now) but loosing the DPAF is a biggie, not to mention the color output and general handling with the touchscreen, etc.
But overall it will be way, way better on an EOS R body in the same way that Sony lenses are way better on the Sony body (having dual stabilisation working together seamlessly).
So if you are not a tripod shooter, this system jumping doesn't make that much sense. At least manual lenses with a decent adapter won't have problems on any of these cameras.
And while watching DRTV in the old days, I've learnt that you can interchange camera straps as well.
 
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dak723

EOS R
Oct 26, 2013
1,141
435
Summing it up, it is pretty pointless to have both systems....

I am interested in the new FF mirrorless and already have the M5. I would say that they both will serve a different purpose and will get equal use. When I want small and conveneient, I will take the M5. When I want maximum quality, I will take the R. The M5 is so much smaller and lighter, it will still serve a very big purpose for many, in my opinion. I would have absolutely no interest in using lenses for one system on the other. RF lenses will be way to big and heavy for the M5.
 

dak723

EOS R
Oct 26, 2013
1,141
435
Interesting read, but I still struggle in reading the tea leaves. The transition to EF from FD made sense in that it added a new functionality which one could argue created a significant shift in the industry. I'm really curious about what RF can do that EF couldn't - or maybe it is just the 24mm of flange?

It just seems odd to build the most robust lens lineup available only to loosen the grip on that advantage over the competition unless it is for the long-term good. Sure, EF is still functional using the adapter, but if users are willing to use an adapter to mount EF to RF, then it isn't as much of a reach to mount EF to E or Z.

Don't get me wrong, I'm on board for a compact full frame kit but I just don't understand the decision yet. Hopefully we'll know more tomorrow!


I think there are no tea leaves to read yet. I do not think that Canon is thinking of this as a transition - at least not yet. For now, mirrorless is just another alternative. I don't think DSLRs and EF lenses are going away any time soon.
 

AJ

EOS RP
Sep 11, 2010
714
129
I think RF will affect me if Canon has the mount patented and doesn't allow third-party lenses. Right now we're spoiled for choice: Sigma, Zeiss, Tamron, Samyang, you name it. There are hundreds of lenses that fit the EF mount. The beauty of the EF mount is that it opens up the doors to competition and innovation. It'd be sad if this is taken away from us.
 

padam

EOS R
Aug 26, 2015
1,233
893
I am interested in the new FF mirrorless and already have the M5. I would say that they both will serve a different purpose and will get equal use. When I want small and conveneient, I will take the M5. When I want maximum quality, I will take the R. The M5 is so much smaller and lighter, it will still serve a very big purpose for many, in my opinion. I would have absolutely no interest in using lenses for one system on the other. RF lenses will be way to big and heavy for the M5.
If you have some money to burn, sure, it's not priced to be that high.
That's what Canon have been trying to achieve with the widening of their product range, and there are professionals who have many different tools, where one one thing does slightly better than the other, at least now I see cameras as being way more universal than they used to (and yet they still try to limit and segmentate them as much as they can while at the same time pricing them according to their functionality)

I would be very surprised to see this new camera at the 2000$ mark, when I think it as more of a Z7 competitor.
 

amorse

EOS RP
Jan 26, 2017
797
1,084
www.instagram.com
I think there are no tea leaves to read yet. I do not think that Canon is thinking of this as a transition - at least not yet. For now, mirrorless is just another alternative. I don't think DSLRs and EF lenses are going away any time soon.
I think you're right in that EF isn't going anywhere any time soon (I certainly don't have my EF glass up for sale), but I am very curious to know Canon's long-term vision. Is the intent that EF will be eventually retired or will RF be a parallel offering? Obviously, anyone investing in RF mount will not be able to transition that investment to EF, so the upgrade pathway that existed between EF and EF-S is not being replicated here, unless it is EF to RF.

I'm hoping that Canon provides some comment on the future of the RF mount - obviously they mean business if they're offering lenses not currently available in EF - that incentivizes transition to the alternative system. I'd love to hear the justification for mount transition - it may give us an idea of the type of gear they plan on releasing in the next several years, and where RF is headed.

For me, I am becoming more and more interested in an EOS R as a backup to my 5D IV, but the more I think about it the more I wonder if the next body would result in the 5D IV being the backup to whatever comes next.

...Then again, my GAS could use a break too!
 

traveller

EOS R
Jul 22, 2010
895
58
I can see where Keith is coming from here, but if EF-M is not to be part of the greater-EOS ecosystem in future, then it is inevitably ******* to the scrapheap as surely as all those previous Canon mounts. What I find a touch strange is that Canon is also rumoured to be releasing the high-end orientated EF-M 32mm f/1.4 STM at the same time as orphaning EF-M from the RF future.

EDIT: as an aside, it will be interesting to see what Panasonic do with their rumoured full frame system (due to be 'pre-announced' on 25th September) and how it will relate to their existing m4/3 system.
 
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psolberg

EOS RP
Feb 8, 2012
619
17
well he doesn't dismantle the upgrade path argument. He just says
I believe that there is far too much read into some spurious ‘upgrade path’ from basic Rebel, through xxD and on to the dizzy heights of the 5 and 1 series.
okay, well that's a personal belief. It doesn't really negate that somebody else may legitimately want to buy a 7D and eventually a 5D or 1DX without necesarily owning everything in between, or likewise an M50 and then whatever R body suits them. It also doesn't negate the backup body argument as some suggested where you don't sell your cropped sensor camera, but keep it as a second body before you can get a second FF body. Simply driving over people's concerns with the good old: "go out and shoot with what you have" cliché is ok but does not invalidate the concerns. In particular when it is their money, not yours that they will spend.
 

psolberg

EOS RP
Feb 8, 2012
619
17
The Z-mount has those golden contacts is a very different place so the adapter is fiddly to make, maybe that has had something to do with the Nikon F -> Sony E adapter actually making cameras non-functional. And we can add that the flange distance being so close, I really don't think of this as being feasible. This is nothing like mounting Nikon F lenses with manual mechanics on a Canon EF body.

Yes, you can use EF lenses on the E-mount if you need features that the Sony offers that's a given. Like FF 4k or higher framerates, built-in IS, dual cards slots (for now) but loosing the DPAF is a biggie, not to mention the color output and general handling with the touchscreen, etc.
But overall it will be way, way better on an EOS R body in the same way that Sony lenses are way better on the Sony body (having dual stabilisation working together seamlessly).
So if you are not a tripod shooter, this system jumping doesn't make that much sense. At least manual lenses with a decent adapter won't have problems on any of these cameras.
And while watching DRTV in the old days, I've learnt that you can interchange camera straps as well.

Adapting the mechanical and various complexities of the undocumented F protocol to sony is the problem more than routing the cables from the bottom of the adapter to the top. So the experiences with the F-E adapter are irrelevant as it pertains to the Z mount. How many adapters will be made for Z and R mounts depends more on the willingness of either company to be open about the protocols, or the ability of the reverse engineering team. The reason sony chose to open up the specs is because contact routing, machining, etc, are not as difficult to get right because of the state of electronics and precision part manufacturing today, in particular for cases where you're adapting a mount of similar size but that it sits much farther way from the sensor. There is plenty of room.

Said that, I think an EF-Z adapter is a given because it would be very popular and capitalize on people's willingness to adapt things these days, including its target customer: Z buyer, who is adapting lenses anyway. I imagine metabones and others are just waiting to get their hands on Z bodies and lenses to evaluate the Z protocol and reverse it. They already understand canon's EF, and given both Z and EF are fully electronic, they don't have to worry about weird links, levers, screws, etc that are such a pain in the F mount.
 
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padam

EOS R
Aug 26, 2015
1,233
893
Adapting the mechanical and various complexities of the undocumented F protocol to sony is the problem more than routing the cables from the bottom of the adapter to the top. So the experiences with the F-E adapter are irrelevant as it pertains to the Z mount. How many adapters will be made for Z and R mounts depends more on the willingness of either company to be open about the protocols, or the ability of the reverse engineering team. The reason sony chose to open up the specs is because contact routing, machining, etc, are not as difficult to get right because of the state of electronics and precision part manufacturing today, in particular for cases where you're adapting a mount of similar size but that it sits much farther way from the sensor. There is plenty of room.

Said that, I think an EF-Z adapter is a given because it would be very popular and capitalize on people's willingness to adapt things these days, including its target customer: Z buyer, who is adapting lenses anyway. I imagine metabones and others are just waiting to get their hands on Z bodies and lenses to evaluate the Z protocol and reverse it. They already understand canon's EF, and given both Z and EF are fully electronic, they don't have to worry about weird links, levers, screws, etc that are such a pain in the F mount.

That's the only variation that's actually plausible, although it still really doesn't make much sense apart for tripod use and the makers of lens adaptors, it's good business for them.
Even if they adapt it super well, is it going to be function any better than F-mount lenses, having better than 3-axis stabilization? No. But unlike those, will they support dual IS? No. Will they work like with DPAF? No, not even close. Is it going to be better for video overall? Probably not for 95% of the people and the rest have other choices than the EOS R.

Sony is supporting this idea because they didn't really have much choice and now it is simply better to use a native lens but they still sell cameras.
Nikon on the other hand sells other cameras and wants to sell lenses (any types that they make) and XQD cards.