Patent: 500mm and 600mm diffractive optic lenses

Canon Rumors Guy

EOS 1D MK II
Jul 20, 2010
7,333
187
Canada
www.canonrumors.com
Here is another in a long line of diffractive optics patents we’ve seen from Canon over the last couple of years. Since the Canon EXPO in 2015, we’ve all been wondering where the EF 600mm f/4 DO IS lens is, a lens we don’t think is ever coming at this point. A lot has changed over the last 3 years, and we expect any new DO super telephoto lens to be for Canon’s new RF mount.
This latest USPTO patent showcases both a 500mm and 600mm optical formula. As Canon News points out, this patent shows Canon moving the lens elements closer to the camera body to improve balance. This is the same sort of design we saw in the brand new EF 400mm f/2.8L IS III and EF 600mm f/4L IS III lenses.
Example 1:

Focal Length: 487.49mm
F-Number: 4.12
Half angle of view: 2.54º
Image height: 21.64mm
Total lens length: 409.74mm
Backfocus: 98.42mm...
Continue reading...


 

wtlloyd

EOS RP
Sep 1, 2010
265
0
Kihei, HI
"where the EF 600mm f/4 DO IS lens is, a lens we don’t think is ever coming "
Ya, pretty much. Why would they, with the new VerIII lens weight reduction. If a DO 600mm ever comes, it'll be RF mount.
 

DanCarr

I'm New Here
Apr 15, 2015
15
10
The odd thing about these is that they are actually listed as being physically longer than existing non-DO 500 and 600s.
 

applecider

EOS 7D MK II
May 20, 2012
486
42
Portland Oregon, Cape Cod
I get that ML is the new platform, but EF lenses are so adaptable and the R are good only for the very short back focus. Is it just sour grapes that I want EF lenses or is canon pulling an FD to EF switch in a sort of non mandatory way. That switch gained autofocus, this one gets higher frame rates, better servo focus, less expensive lenses. Lighter equipment.

Is there a third party lens for the R mount yet?

I thought that canon was way ahead of Nikon in the DO space, but right now it looks like a leap frogging situation.
 
Reactions: YnR

Mr Majestyk

EOS T7i
Feb 20, 2016
97
19
Why release 400/600 mk III in EF and not a 300/500 mk III in EF. Currently, we have no idea if Canon can even offer an RF mount camera worthy of such lenses. They need a quantum leap over the pitiful EOS R AF system to make it worthwhile. Also could these be made much lighter than refractive counterparts? 600III is 3kg, unless you can get that down under 2.7kg and physically shorter is it worth it? Now if they can deliver a 500 f/4 DO at around 2-2.3kg and offer Sony A9 class AF in an EOS R then I'll be first in line.
 

RGF

How you relate to the issue, is the issue.
Jul 13, 2012
2,814
34
To release a RF mount supertele Canon will need an R body with high FPS for action. This should be interesting ... in 3 to 5 years :D
 

AlanF

5DSR
Aug 16, 2012
4,664
1,171
The lens I would lust after would be a rival to the Nikkor 500mm f/5.6 PF (DO equivalent). It's close to the same length as the 400mm DO II (237mm), weighs only 1.46 kg (vs 2.1 kg + 200g hood of DO) and takes 95mm filters. It's lighter than the 100-400mm II f/5.6. And a diminutive 400 f/5.6 DO under a kg would be irresistible.
 

sulla

EOS RP
Dec 31, 2012
240
1
Austria
www.flickr.com
"we expect any new DO super telephoto lens to be for Canon’s new RF mount"

Why should it? RF mount is perfect for lenses with a short backfocus, like lenses with a focal length of up to ~100 mm. I don't see a benefit of the RF mount for longer lenses: (super) telephoto lenses have a huge backfocus anyway (as is also shown in this patent), that makes them perfectly suited for the EF mount. I think it makes just more sense to make those lenses physically shorter EF lenses an use an adapter for RF mounts than make them physically longer (with an empty tube at the back) and make them RF-natively. At most, Canon could release EF- and RF- supertelephotolenses of the very same design just a different end-barrel (plus offer a mount conversion service).

The only advantage I can imagine could come from the (slightly) larger mount diameter of the RF mount, but I have no idea whether that makes designing RF-supertelephoto lenses easier than EF-supertelephoto lenses. But it could be... But for the back focus: no!
 

Joules

EOS 80D
Jul 16, 2017
125
40
Hamburg, Germany
The only advantage I can imagine could come from the (slightly) larger mount diameter of the RF mount, but I have no idea whether that makes designing RF-supertelephoto lenses easier than EF-supertelephoto lenses.
Correct me if I'm wrong, but is the RF mount not the same in diameter as the EF mount? Wikipedia and the Canon page where they announced the new mount both list 54mm as the inner diameter for both mounts.

So apart from avoiding the use of an adapter there should be no mechanical/optical advantage to making an RF supertele lens over an EF one.

The note from DanCarr about the sizes is interesting. According to the Canon Website the current 600mm III is 448mm long and the post above suggests the DO version would be 474mm long. Am I missing something about the way these are measured?

The increase could be explained in part by the addition of 24mm empty tube to an RF lens. But if a DO Version actually becomes bigger than its regular counterpart, I imagine the weight the reduction would have to be really significant to still sell well.
 

docsmith

EOS 6D MK II
Sep 17, 2010
817
159
The note from DanCarr about the sizes is interesting. According to the Canon Website the current 600mm III is 448mm long and the post above suggests the DO version would be 474mm long. Am I missing something about the way these are measured?

The increase could be explained in part by the addition of 24mm empty tube to an RF lens.
If that is it, I would almost rather have EF supertelephotos and use an adapter. That would make packing/travel a bit easier.
 

koenkooi

EOS 80D
Feb 25, 2015
178
59
The previous post
https://www.canonrumors.com/the-benefits-of-the-large-diameter-of-the-eos-rs-rf-mount-explained/
explains, that the RF mount is larger than the EF-M mount.

UPS. I confused EF-M with EF/EF-S. Yes, indeed, RF and EF mounts have the same inner diameter of 54mm.

So, really no reason I see to make large backfocus lenses with a native RF mount...
No technical/mechanical reason you mean. Plenty of business and marketing reasons to make it an RF lens.
 

Tom W

EOS 80D
Sep 5, 2012
133
60
The odd thing about these is that they are actually listed as being physically longer than existing non-DO 500 and 600s.
I checked, and saw that. Unless the length would include the hood, I don't see the advantage. The 500 f/4 II IS is an awesome lens. Lightening and/or reducing the size is what it needs. But if they do to it what they did to the 400 and 600, then I'm not sure that there's a place for DO.
 

Tom W

EOS 80D
Sep 5, 2012
133
60
The previous post
https://www.canonrumors.com/the-benefits-of-the-large-diameter-of-the-eos-rs-rf-mount-explained/
explains, that the RF mount is larger than the EF-M mount.

UPS. I confused EF-M with EF/EF-S. Yes, indeed, RF and EF mounts have the same inner diameter of 54mm.

So, really no reason I see to make large backfocus lenses with a native RF mount...
They could easily make any of the super-telephoto lenses in either EF or R mount as the situation demands. The backfocus distance is much larger than the spacing between the lens and sensor on either mount.

The big differences would be no adapter needed for the R mount, and the additional communications that R offers between the lens and the camera. Optically, they could essentially be identical.
 

Architect1776

Defining the poetics of space through Architecture
Aug 18, 2017
154
117
117
Williamsport, PA
"we expect any new DO super telephoto lens to be for Canon’s new RF mount"

Why should it? RF mount is perfect for lenses with a short backfocus, like lenses with a focal length of up to ~100 mm. I don't see a benefit of the RF mount for longer lenses: (super) telephoto lenses have a huge backfocus anyway (as is also shown in this patent), that makes them perfectly suited for the EF mount. I think it makes just more sense to make those lenses physically shorter EF lenses an use an adapter for RF mounts than make them physically longer (with an empty tube at the back) and make them RF-natively. At most, Canon could release EF- and RF- supertelephotolenses of the very same design just a different end-barrel (plus offer a mount conversion service).

The only advantage I can imagine could come from the (slightly) larger mount diameter of the RF mount, but I have no idea whether that makes designing RF-supertelephoto lenses easier than EF-supertelephoto lenses. But it could be... But for the back focus: no!
EF and RF mount diameter are identical 54mm.
 

Architect1776

Defining the poetics of space through Architecture
Aug 18, 2017
154
117
117
Williamsport, PA
Correct me if I'm wrong, but is the RF mount not the same in diameter as the EF mount? Wikipedia and the Canon page where they announced the new mount both list 54mm as the inner diameter for both mounts.

So apart from avoiding the use of an adapter there should be no mechanical/optical advantage to making an RF supertele lens over an EF one.

The note from DanCarr about the sizes is interesting. According to the Canon Website the current 600mm III is 448mm long and the post above suggests the DO version would be 474mm long. Am I missing something about the way these are measured?

The increase could be explained in part by the addition of 24mm empty tube to an RF lens. But if a DO Version actually becomes bigger than its regular counterpart, I imagine the weight the reduction would have to be really significant to still sell well.
EF and RF are 54mm in diameter.
 

juststeve

I'm New Here
Nov 29, 2018
11
18
I am currently renting an R and the 24-105/4 L This past week I spent two days photographing bald eagles, mostly in flight, using the R, the control ring adapter and a 500/4 L ii with and without a 1.4x.

Those who claim the R focuses poorly should perhaps use one for a bit of time in real photo world conditions. For me the camera focused the 500 very, very well, at least on par with my 7D ii and 5DS, and likely better. Yes, there is a bit of a stutter in the viewfinder at 5 fps. I found it minor and did not hinder me. If it had I would have switched out camera bodies. Instead, I used it for nearly 900 exposures.

Also, I photographed my border collies chasing frizbees. I did it from in front of the dogs near where they were making their catches, using the RF 24-105/4. When I performed keeping the camera on target well, the camera focus system performed well. Same as with the flying eagles. I found interesting the camera did not seem to have the viewfinder stutter at 5 fps with the RF lens. Perhaps the capability of much higher rate communication between lens and camera with the RF mount explains this. This would certainly make purchase of fancy DO RF lenses tempting. Likely increase the divorce rate, too.
 

lexptr

EOS M50
Aug 8, 2014
35
3
www.len-lex.com
I see news and rumors about those two again and again but still don't get the point. They add DO while, unlike with 400mm, retain the same max aperture. So, I guess, it will be even more expensive and have narrower customers niche. So, what for? With their recent advancements in weight reduction of mark III versions, the possible specs-profit is even smaller.

What could be interesting to many, I think, is adding some good cheaper options. E.g. 500mm f/5.6 DO (like the Nikon's one) or 200-600mm f/4.5-5.6 (a rumored "larger" 100-400mm). Here I can see a source of possible hesitation (aside from development difficulties and times) - fear to draw some customers from their more expensive lenses. On other hand, many will buy such lenses for sure. I would. And this wouldn't draw me from expensive super-tele, since I don't think I will ever justify five-figure price for a single lens.