Opinion Rumors

Canon Full-Frame Mirrorless Rumors And Analysis

With very little information to go on about the rumored announcement on September 5th, I’m going to talk about some of the ideas pointed out in regard to a Canon mirrorless full-frame camera.

Not too long ago I transitioned to a pair of Canon EOS M50 camera bodies with the 22mm f2, 11-22mm, and 15-45mm kit lens primarily for solo video work. The M50 is such a nice little camera that I’ve been using it for photos a lot as well. EF-M is now a solid system thanks to DPAF, though the M50 lacks a few things I’d like to have, and also hasn’t had great lens release support from Canon. Overall I’m happy with the setup given the great DPAF in video, fully articulating screen, and solid Android app. I did own the original EOS-M camera… what a huge improvement the M50 is in every regard! Anyways…

First off let’s talk about the most well known rumors such as this one.

The frequently mentioned quote about a “sexy” solution to mirrorless full-frame with Canon is odd. I’ve never seen this interview where the word was mentioned and can only guess the context.

* There is talk about keeping the EF mount. In that case you would get what is effectively a mirrorless camera, but with a large hole where the mirror and whatever else resided. Pentax did this with their K-01 mirrorless camera years ago. I think the idea is generally fine, but not ideal for some people. I think it would be great to still offer DSLR style cameras with mirrorless innards and leave it at that. This isn’t something I’d want, but I could see it as a benefit to photographers that have extensive EF lens collections. There are inherent benefits to this approach given what mirrorless can do over DSLRs. The days of misaligned DSLR focusing systems would be gone. Not to mention the what-you-see-is-what-you-get electronic viewfinder. Another plus could come in the form of something (very unlikely) such as an integrated variable ND filter in the camera where the traditional DSLR components took up space. That would be a huge benefit to some videographers and photographers. A feature like that would peak my interest in this.

Where things start to get strange, and extremely unlikely in my opinion, is the idea that lenses would be developed to fit inside that empty space in the camera. So you would effectively have the camera with not much lens extending past the mount. I’d speculate that there would be issues with lens designs and trying to fit optics and electronics in the space that comprises the current EF mount’s diameter. I don’t see this happening and can’t see much if any benefit (though I’ll say that Pentax should have kept iterating their K-01… by now it could have been something interesting). One issue of this route is that you couldn’t adapt any existing lenses from mounts that have a shorter flange such as the L39 mount. The EF mount is better than say Nikon’s F-mount, but isn’t ideal. I’ve started adapting film era glass to my Canon M50 and it’s really enjoyable (my next Youtube video will likely be about that).

* There is talk of having the sensor shift. This is even more unlikely than having lenses designed to fit in the empty space. It also provides even less benefit outside of being able to adapt more mounts to the system. Technically it might be able to adapt everything that has a shorter flange, but the issue would come with precision. I don’t see this happening and wouldn’t want it to.

* There is talk about having the mount section expand and contract. While it could make the camera more compact thickness wise, it adds unnecessary complexity and cost to the system. I also couldn’t see that being robust over the long term. You’re adding moving parts, which causes issues with weather resistance and reliability. Imagine holding the camera alone and having a large EF lens attached. How large of a lens would start to put a lot of downward force on this extending barrel that it causes image quality issues where the top or bottom of the photo is out of focus? A non-starter… (hopefully).

* There is talk about the EF-M system getting a full-frame sensor camera. Though this would be my ideal outcome, I think it’s less likely than some of the other options. The main issue is that the mount diameter isn’t ideal for a standard full-frame sensor. It’s very close to Sony’s E-mount in size, but there appears to be some drawbacks to the smaller mount size in general. Nikon leapfrogged the issue by designing a nice large mount diameter into their new Z mount, but Canon apparently didn’t or never had the intent to put a larger sensor into EF-M.

One potential option I’d be fine with is if Canon does something similar to what they did with their APS-C cameras. Their sensors have a 1.6x crop factor instead of 1.52x that other systems use. If they downsized the traditional full-frame sensor size a bit to make it fit some performance threshold they were after, I’d expect it to work out fine. The chance of that happening is a lot more likely with Canon than other brands because they make their own sensors. I have seen a few comments here and there about some quote saying EF-M was never intended to be “professional”, which would cancel out the chance of EF-M getting a larger sensor. I haven’t seen the actual quotes, but I’d tend to agree with it.

The reason I’d like this to happen is that I’d expect more dedicated lenses to be released for the EF-M mount. I’d expect more support in general for both FF and 1.6x crop. I’d be very likely to sell off my Nikon equipment and go straight Canon if this happens (as long as all of the specifications of the to-be-released camera align with my needs). I’d have the benefit of going super small with something like the M100, but adding on something like an 85mm full-frame EF-M prime to it. Maybe not the most ergonomic setup in that specific case, but it would be a native option I’d potentially own. Sure, current EF-M lenses wouldn’t be ideal on a full-frame camera, but I’d expect them to at least work in a crop mode (super 35 video is a thing and current lenses like the 11-22 would be fine there).

I’d assume Canon would have to re-design their EF to EF-M adapter, though I have no idea on that. I don’t have one because I don’t have any EF lenses.

Though, that possibility hits the roadblock of whether Canon wants a large diameter mount for their FF mirrorless moving forward or not.

* The route I expect Canon to take is making a new full-frame mirrorless mount. It would be almost exactly the EF mount, but with the registration distance shortened. The main issue that comes with this route is that I could easily see it cutting out compatibility with EF-M. At a registration distance of 18mm for EF-M, this new mount with have to be some technically decided length longer so that an adapter could be made that would allow the new lenses to fit on EF-M. I don’t know how much longer the registration distance would need to be in that case. Considering Nikon is 16mm for their Z mount, canon could go that route as well which would effectively make it impossible for EF-M cameras to use the new lenses. I hope if this is the route that happens that they figure something “sexy” out so EF-M can use the lenses. The main issue I see is that with a longer registration distance the Nikon Z system will have the edge in being able to have thinner cameras. This rumor is currently called the “RF mount”. With this design Canon could make a very simple and robust adapter for EF lenses. I don’t see why it couldn’t be basically a 1:1 diameter tube with contact pass-through. Maybe even cheap enough that EF lens owners could buy a bunch of them and leave them on the lenses.

All that said, I’d prefer that Canon make something like a large sensor M50 in EF-M mount. The camera would keep the fully articulating screen (this is a must have for me). It would also be larger, have a taller thicker grip, have more physical controls, and of course the larger sensor. At that point they could develop a mixture of lenses for the two sensor sizes, though I’d expect 1.6x crop sensor to have fewer new releases. That isn’t a huge issue because we would get more native lenses overall for EF-M moving forward. Otherwise, a new mount seems like the smartest option for them overall as long as they can somehow design it in such a way that the lenses could adapt to EF-M.

EDIT: (Link 1 in Japanese, and Link 2 in English) It looks like Canon is going the new mount route with adapters. The new mount is only 2mm longer in flange distance than the EF-M mount, so I don’t expect these lenses to work with EF-M system. That is rough, but overall the camera looks promising with the fully articulating screen, tall grip, and a ton of buttons/dials. The other negative is that the memory card door looks a bit small. They could potentially fit two SD cards in there, but I’m starting to think they went with a single card (I hope not… this whole dropping the second card from expensive cameras is getting old). If these photos and specifications are generally correct I expect this camera to be the most popular vlogging camera. There will be a hundreds of Youtube videos made about how great it is for that use case, haha. Well that is if the 4k is decent and it has 120fps at 1080p.

PS: Canon please consider making “body cap lenses” for the EF-M mount. Similar to the 9mm and 15mm Olympus m4/3 lens cap lenses. I’d be very interested! Well, I mean make more native glass in general but body cap lenses would be fun and cheap.