Canon exec confirms that the EOS-1D X Mark III is Canon’s last DSLR

[Nemorino]

The solid technical reason is the shorter flange focal distance. It's 20mm for RF, 44mm for EF.

Yes, but don't forget the new electronics. The new mount has been a good moment to get them up to date.

. So, in 1987, Canon rendered all of its existing lenses obsolete.

Untill the R mount was introduced. Now You can use those old lenses with an adapter again.

 

[AJ]

The solid technical reason is the shorter flange focal distance. It's 20mm for RF, 44mm for EF. Granted, Canon could have kept the same flange distance but that would mean EOS R bodies that were substantially bulkier than they needed to be. In that case, instead of people complaining about greedy Canon using a new mount, people would be complaining about stodgy Canon not leveraging one of the advantages of new technology.

So from all of this I conclude that with RF, we ended up with smaller and less bulky bodies but lenses that are about the same size and weight.

 

[PhotoGenerous]

The fact that you’re citing TN pretty much torpedos anything else you have to say. I guess you like misinfotainment.

Incidentally, for the month of November the best-selling ILC in Japan was the Kiss X10 2-lens kit. That’s the domestic name of the 250D/Rebel SL3…a DSLR. So yeah, it makes sense to some people that Canon wants to kill off DSLRs ASAP...just like the earth being flat makes sense to some people.

The whole point of the link was that he asked for Japanese speakers to help translate the article and I provided the actual replies from Japanese speaking people, some that didn't even seem to line up with his conclusion.

But who wants more sources of information? It has the Tony Northrup name so "obviously" its incorrect and meaningless, even when it's not about in misinfotainment.

Let's blanket not even look at information just because it's Tony Northrup adjacent says the person who is always claiming a desire for more data and facts.

 

[AlanF]

Yes, but don't forget the new electronics. The new mount has been a good moment to get them up to date.

Untill the R mount was introduced. Now You can use those old lenses with an adapter again.

The FD lenses were being used on mirrorless years before the R mount on Sony E for example with Metabones, Fotodiox etc adapters.

 

[neuroanatomist]

So from all of this I conclude that with RF, we ended up with smaller and less bulky bodies but lenses that are about the same size and weight.

Perhaps semantics, but while that's true from the reductionist viewpoint of considering only the mount, the fact is that the mount was used for mirrorless camera. The lack of a mirror is what makes the shorter flange distance possible (don't need room to flip up the mirror). But mirrorless allows on-sensor phase-detect AF while looking through the viewfinder, and that means AF can work at very narrow apertures. Thus, we have lenses like the 800/11 that simply weren't possible as AF lenses for a DSLR. There's no direct comparison, but an 800mm lens that doesn't weigh 10 pounds and cost >$12K is possible with the RF mount but not the EF mount. Also, the fact that the view 'through the lens' really isn't but rather is through an EVF means lenses like the RF 16/2.8 can be designed with weaker optics that require algorithmic corrections but are much smaller, lighter and cheaper than an optically corrected EF lens.

Having said that, it is correct that the benefits of the mount itself are minimal when comparing functionally equivalent lenses between EF and RF.

 

[dcm]

The FD lenses were being used on mirrorless years before the R mount on Sony E for example with Metabones, Fotodiox etc adapters.

I even dabbled with FD lenses on EOS Ms via an adapter.

 

[AJ]

it is correct that the benefits of the mount itself are minimal when comparing functionally equivalent lenses between EF and RF.

Surely there must be some design benefits in the possibility of having elements closer to the sensor. Maybe this just hasn't been realized yet in the current lineup. Maybe the 14-21/1.4 and the like are still to come.

 

[neuroanatomist]

Surely there must be some design benefits in the possibility of having elements closer to the sensor. Maybe this just hasn't been realized yet in the current lineup. Maybe the 14-21/1.4 and the like are still to come.

I'm not sure a 28-70mm f/2 would have been possible for EF.

 

[privatebydesign]

I'm not sure a 28-70mm f/2 would have been possible for EF.

Surely if you can have an EF 28 f1.8 and an EF 85 f1.2 an EF 28-70 f2 would have been possible with the mount.

 

[SnowMiku]

If you pull the battery out momentarily after turning it off and then put the battery all the way back in, does the transmissive screen power back up or always stay off with the 90D?

I tested it out just then. When pulling the battery out after turning off the camera the transmissive screen will stay on until the battery is removed. When you insert the battery back in then close the battery door the transmissive screen will power on.

 

[neuroanatomist]

Surely if you can have an EF 28 f1.8 and an EF 85 f1.2 an EF 28-70 f2 would have been possible with the mount.

I’m not so sure. Prime lenses are far less complicated designs than constant aperture zoom lenses, particularly ones that span wide to telephoto ranges.

 

[SnowMiku]

Not really, the technical reasons to go to a much wider mount mouth made sense, however the trimming of a couple of mm in flange distance didn't make as much sense to me and that is what killed the possibility of adapters. I was heavily invested in FD at the time (I sold my FD 135 f2 a couple of days ago). The change certainly caused enough of a headache for Canon and their users that I don't think another incompatible mount change would ever be on the cards.

Except for EF-M and RF

 

[privatebydesign]

Except for EF-M and RF

Well at this point there isn’t an EF-M lens that covers the image circle of any R cameras, so there’s that...

 

[SnowMiku]

Well at this point there isn’t an EF-M lens that covers the image circle of any R cameras, so there’s that...

I was thinking more of an RF lens on an M body.

 

[privatebydesign]

I was thinking more of an RF lens on an M body.

That is physically possible, but there isn’t an M camera with the brain to drive an RF lens so it seems pointless. No focus and no aperture kinda hampers lens functionality.

 

[Michael Clark]

I’m not so sure. Prime lenses are far less complicated designs than constant aperture zoom lenses, particularly ones that span wide to telephoto ranges.

Yes, and the big difference for a 28-70mm lens is that with a 20mm registration distance there's no need for a 28-70mm to be retrofocus at any point in the zoom range.

With a 44mm registration distance a 28-70mm lens must be retrofocus over most of it's focal length range before (potentially) reversing the directions some of the elements move as it continues to be zoomed to longer focal lengths. (e.g. the 18-55mm kit lenses, 28-135mm, 15-85mm, etc.)

The original EF 24-70mm f/2.8L was retrofocus throughout the entire zoom range. That's why it was fully extended at 24mm and fully retracted at 70mm. It's also why the critical adjustments for aligning lens elements were in the very front of the barrel that extended, and could get knocked out of whack very easily if bumped while the barrel was extended.

 

[Michael Clark]

That is physically possible, but there isn’t an M camera with the brain to drive an RF lens so it seems pointless. No focus and no aperture kinda hampers lens functionality.

Not physically possible because the throat diameter of the RF mount is larger than the EF-M mount but the bayonet lugs of the RF mount extend more than 2mm behind the flange. The lugs would need to be inside the EF-M camera's flange ring.

 

[Midge]

In 1987, Canon introduced the EOS system with the EF mount, which superseded the previous FD mount. The distance between the film and the flange of the mount was increased in the EF system, which meant that you couldn't put a simple adapter on the EF mount to take the older FD lenses and have it focus at infinity - the FD lens would be too far away and it would need some correcting lenses in between to get the FD lens to focus further back. The RF sensor to flange distance is much less than the sensor to EF flange, which means you can easily fit an adapter on the RF to take an EF lens and for it to be placed at the correct distance away from the sensor to focus. So, in 1987, Canon rendered all of its existing lenses obsolete. This time around, all existing older EF lenses are forwards compatible.

Thanks for the information. I read somewhere recently that there is now an adaptor that will take fd lenses on a mirrorless body. Is that true or is someone spreading misinformation?

 

[privatebydesign]

Thanks for the information. I read somewhere recently that there is now an adaptor that will take fd lenses on a mirrorless body. Is that true or is someone spreading misinformation?

https://www.bhphotovideo.com/c/product/1460411-REG/fotodiox_fd_eosr_pro_canon_fd_to_canon.html

There are at least half a dozen different companies that make them.

 

[Bishop80]

The EOS R system is all about the mount - the problems it could solve, and provisions given for product growth. From the EOS R White Paper, these were identified as (note: virtually everything below is quoted/copied from their paper):

Problems:

1. Insufficient flexibilities in mount diameter and back focus distance to accommodate all of the increasingly diverse requirements in zoom and prime lenses
   • Large diameter rear lens elements that are much closer to the full frame image sensor - enhancing overall optical performance (in particular, tighter control over optical aberrations at image extremities)
   • Lenses having the same specifications for focal length and maximum aperture as current EF mount lenses - but having significantly higher image quality - within the same size and weight
   • High optical performance, large aperture (F1.2) prime lenses for full frame cameras
   • Zoom lenses of higher brightness with constant aperture over their focal ranges - while still modest in size and weight
   • Two key dimensions play a significant role in the quality of the final image projected on to the image sensor - they are the back focus distance and the diameter of the final lens element.
2. Limited speed of the electronic communication between lens and camera
3. Limited electronic channels between lens and camera to accommodate new operational aspirations
4. Constraints in sensor-based AF operational capabilities

Design considerations for their "ideal" lens-camera system:

1. Emerging popularity of the full frame image sensor
2. Anticipated progressive elevation of sensor resolution
3. Quest for higher exposure range
4. Increasing diversity and sophistication of end-users seeking extended operational functionalities
5. Balancing among these lens parameters:
   • Higher Optical Performance - to accommodate multiple future enhancements in camera performance
   • Enhanced Operational Specifications - such as focal length ranges, maximum aperture, and their controls
   • Meeting demands in Size and Weight Specifications - which can be critically important to certain forms of shooting

Since there are questions about the Rebel series going to EF vs RF mount, APS-C vs full frame, I expect that future cameras within Canon's existing product line that transition to the RF mount would do so it they fall within the above criteria. Maybe they all will... eventually.

Anyway, I posted the above since someone commented along the lines of haven't we hashed through this already? I think it's good to look back occasionally at what the stated goals were - at what was promised/intended, and then see if that has been delivered on. For example, the questions about optical performance and size/weight, etc. I highlighted "optical performance" in the lists above since that was also being questioned, whether they have delivered on that or not, or did they realize they could fudge on physical design and compensate with digital lens correction algorithms? Or maybe that's what they meant all along?

Actually, I have continued purchasing EF (and EF-M) lenses ever since RF was introduced, though I do have an R body