Canon Patent Applicaton: DO Supertelephoto with Built-In Extender

[Richard CR]

In this patent application (2024-149828) we have Canon doing some great things with extenders built into both a regular lens and a diffractive optics lens.

Canon Patent Applicaton: Canon RF 400mm F4L DO IS with 1.4x Extender - Canon Rumors

When you purchase through links on our site, we may earn an affiliate commission. Here's how it works. In this patent application (2024-149828) we have Canon doing some great things with extenders built into both a regular lens and a diffractive optics lens. I'm not sure how much these would...

www.canonrumors.com

 

[EOS 4 Life]

In this patent application (2024-149828) we have Canon doing some great things with extenders built into both a regular lens and a diffractive optics lens.

Canon Patent Applicaton: Canon RF 400mm F4L DO IS with 1.4x Extender - Canon Rumors

When you purchase through links on our site, we may earn an affiliate commission. Here's how it works. In this patent application (2024-149828) we have Canon doing some great things with extenders built into both a regular lens and a diffractive optics lens. I'm not sure how much these would...

www.canonrumors.com

585.00 F2.12 is a typo

 

[Canon Rumors]

I could definitely get behind an RF 400mm f/4 DO IS USM 1.4x. I really enjoyed using the EF DO lens, though I never bought one outside of the rental business.

 

[Maximilian]

I like the idea of a dedicated extender for a specific fixed FL formula.
The extender can be optimized for this formula.
And the 400 DO formula looks attractively short, because of DO.
But I am sure, the price won't be attractive (to me)

 

[duzinsan]

L or nonL?

 

[Canon Rumors]

L or nonL?

Neither... DO (Diffractive Optics). The green ring.



EF 400mm f/4 DO IS USM II // Image from The-Digital-Picture

 

[Canon Rumors]

I like the idea of a dedicated extender for a specific fixed FL formula.
The extender can be optimized for this formula.
And the 400 DO formula looks attractively short, because of DO.
But I am sure, the price won't be attractive (to me)

Well, the EF version II was about $7000 USD if I remember correctly. Version II fixed the contrast issue that was present on the original version. Those who bit the bullet, loved the lens.

This patent shows that this one would only be about 40mm longer than the EF version WITH a TC.

 

[GMCPhotographics]

I could definitely get behind an RF 400mm f/4 DO IS USM 1.4x. I really enjoyed using the EF DO lens, though I never bought one outside of the rental business.

I get the feeling thisis a pilot fish...a marginal lens to test the technology and gauge the reaction.
From a technical perspective, the advantages of the mirrorless format are very suitable for wide angle lenses, but more problematic for the longer telephoto lenses. This is why all of the teleconverters weve seen on the RF mount are slightly inferior to their EF counterparts.

Relatively, compared to the EF mount variants, the teleconverters are effectively placed behind the EF to RF adaptor, very far back and close ot the sensor. If you look at the MFT charts for the EF 600mm f4 LIS III with a 2x mk 3 tc and compare them to the charts for the RF version of this lens with the RF version of the 2x TC, you will see a slightly worse MFT chart resolution for what is an identical lens. Another example is comparing the EF 400mm f2.8 III LIS with a 2 x TC's MFT's and the RF 800mm f5.6 LIS resolution. It's esentially the same EF lens combination but the RF lens has a suprisingly lower resolution, even though it has an inbuilt / dedicated / custom 2x teleconverter at the end of it's optical path.
While the mirrorless mount is great for wide angle lenses it introduces problems with longer lenses, which is ironic because these lenses are the big flagship optics that bring in the big bucks.

This idea of having a flip in teleconverters has nothing to do with us as consumers (as a sales or feature gimmic) but a stab and designing around this issue. Placing the teleconverter earlier in the optical formula greatly helps with the resolution when the converter is engaged. It should also comfortably outperform the dodgy and rather overpriced 1.4x and 2x teleconverters that canon are currently offering on the RF mount. It's why most of Nikon's big tele's have already implemented this design concept and canon are playing pick up behind the curve here. Because canon chose NOT to develop new and dedcated mirrorless super whites, they haven't had the engineering purview to look at these consequences unti now.

As t the DO elements, sure if they actually bring some tangible benefits without the disasterous low contrast and messed up Bokeh of the mk II EF prime. One of the other issues Canon has with refreshing these lenses is their own R&D and build costs increasing on a yearly basis. Each year it gets costlier for Canon to design, develop and put into production one of these complex optical devices. So the retail price has to go up with each iteration of the model.

 

[nemtom]

600 * 1.4 is not 800, but 840.

On the other hand it is looking exciting to have a built in extender, and that it is not at the end.

 

[AlanF]

As t the DO elements, sure if they actually bring some tangible benefits without the disasterous low contrast and messed up Bokeh of the mk II EF prime. One of the other issues Canon has with refreshing these lenses is their own R&D and build costs increasing on a yearly basis. Each year it gets costlier for Canon to design, develop and put into production one of these complex optical devices. So the retail price has to go up with each iteration of the model.

The EF 400mm f/4 DO ii is a superb lens with excellent contrast. I know from personal experience with 2 copies of the lens, and uncle Rog did proper MTF measurements on it as part of a shootout with the other 400mm Canon lens.

The (sort of) Great 400mm Lens Shootout!

I get asked a lot about different telephoto lenses. Is the 400 DO II better than the 400 DO? Which is better, the Tamron 150-600mm or the Sigma 150-600mm? You've probably noticed that I don't answer those questions. The reason is simple. Our optical bench is designed to test lenses up to 2.5kg...

www.lensrentals.com

In his words:
"A lot of Canon shooters want to know how close they can get if they give up a stop of aperture and get the markedly less expensive and amazingly lighter 400mm DO II. The answer is at f/4, the 400mm DO IS II is basically as good, at least in the center 1/2 of the image where most telephoto subjects rest, as the 400mm f/2.8 IS II is at f/2.8."

The 400mm f/2.8 IS II is one of the very sharpest lenses ever. The DO ii is better in his proper testing than the legendary EF 300mm f/2.8 ii with the 1.4xTC as I can personally testify with my copy of the 300/2.8.

 

[Canon Rumors]

The EF 400mm f/4 DO ii is a superb lens with excellent contrast. I know from personal experience with 2 copies of the lens, and uncle Rog did proper MTF measurements on it as part of a shootout with the other 400mm Canon lens.

The (sort of) Great 400mm Lens Shootout!

I get asked a lot about different telephoto lenses. Is the 400 DO II better than the 400 DO? Which is better, the Tamron 150-600mm or the Sigma 150-600mm? You've probably noticed that I don't answer those questions. The reason is simple. Our optical bench is designed to test lenses up to 2.5kg...

www.lensrentals.com

In his words:
"A lot of Canon shooters want to know how close they can get if they give up a stop of aperture and get the markedly less expensive and amazingly lighter 400mm DO II. The answer is at f/4, the 400mm DO IS II is basically as good, at least in the center 1/2 of the image where most telephoto subjects rest, as the 400mm f/2.8 IS II is at f/2.8."

The 400mm f/2.8 IS II is one of the very sharpest lenses ever. The DO ii is better in his proper testing than the legendary EF 300mm f/2.8 ii with the 1.4xTC as I can personally testify with my copy of the 300/2.8.

Having used the EF 400mm f/4 DO IS USM II on a couple of safaris alongside the EF 400mm f/2.8L IS USM II. They were very close in performance and I didn't notice any autofocus issues with the DO lens that were present on version 1 due to the contrast issue. I recommended the version 2 DO lens without hesitation to everyone and anyone that asked about it.

 

[GMCPhotographics]

The EF 400mm f/4 DO ii is a superb lens with excellent contrast. I know from personal experience with 2 copies of the lens, and uncle Rog did proper MTF measurements on it as part of a shootout with the other 400mm Canon lens.

The (sort of) Great 400mm Lens Shootout!

I get asked a lot about different telephoto lenses. Is the 400 DO II better than the 400 DO? Which is better, the Tamron 150-600mm or the Sigma 150-600mm? You've probably noticed that I don't answer those questions. The reason is simple. Our optical bench is designed to test lenses up to 2.5kg...

www.lensrentals.com

In his words:
"A lot of Canon shooters want to know how close they can get if they give up a stop of aperture and get the markedly less expensive and amazingly lighter 400mm DO II. The answer is at f/4, the 400mm DO IS II is basically as good, at least in the center 1/2 of the image where most telephoto subjects rest, as the 400mm f/2.8 IS II is at f/2.8."

The 400mm f/2.8 IS II is one of the very sharpest lenses ever. The DO ii is better in his proper testing than the legendary EF 300mm f/2.8 ii with the 1.4xTC as I can personally testify with my copy of the 300/2.8.

Soz Alan, I did mean to type mkI not mkII. it was a genuine typo on my part. The mkII is a whole different ball game when compared to the mkI.

 

[[email protected]]

I recognize the low odds of any patent becoming a real lense, but these are the potential ones I'm most excited about - especially the 600/800.

I carry a 600 f/4 (EF III) on my main body with a 1.4x teleconverter (EF). In theory, I can take the TC off, and I do about once a month. In reality I use 840mm as the focal length for almost everything because it takes too much time to swap.

Yesterday morning was the last example. Foggy morning on the Connecticut with sunrise just popping over the white pines on the New Hampshire side. A double-scull of rowers was cruising through the mist, backlit with the sun diffused through the fog. I had maybe 30 seconds to swap out the TC and throw it in my sandy and linty jacket pocket. Plenty of time. But I didn't. There's a friction to doing this. It's the linty pocket; I'm not sure how big the rowers will be in the frame until I have them framed; I'm not positive I had 30 seconds; etc. The result: a shot of a single rower in a gray background instead of the visually stunning scene I could see with my eyes. A simple switch would be a game changer for me.

Canon has previously stratified pricing with DO lenses to make them cheaper than the red-ringed ones. I think this is one reason why they many not have ever done the 600 DO. It would have been a revenue give-away. For my part, I'd pay more that the 600 f/4 for the 600/800 DO.

Also, a big liability for the current f/4 lenses is the length. I will often find myself using it out a car window, and getting that beast - however light - turned around and pointing toward the moose is another 10 seconds.

All that said, I think we have a ratio of perhaps 1/15th of patents becoming lenses, and even then perhaps an average of 3-4 years after publication. Not holding my breath. Precedent tells us we'll instead get another 600 with the same optical design, slightly different shade of white, and $2,000 added to the price. -tig

 

[GMCPhotographics]

The 400mm f/2.8 IS II is one of the very sharpest lenses ever. The DO ii is better in his proper testing than the legendary EF 300mm f/2.8 ii with the 1.4xTC as I can personally testify with my copy of the 300/2.8.

Just to clarify some points when comparing the MFt charts of the Canon 400mm lenses. The EF 400mm f2.8 II LIS is the sharpest of the lot. It's as sharp with a 2x TC as the mkIII is with a 1.4x TC. In terms of teleconverter reach / brightness / IQ there's a lot of similarities between the EF 600mm f4 LIS II and it's a prety close race with slight pros and cons on both optics. Basically the mkII versions of the EF 300mm f2.8 / 400 f2.8 and 600mm f4 are all superlative.

However, while the mkII f2.8 is certainly sharper, this will only translate into photographs when using a 2x TC wide open on maybe an R5.
The problem with 400mm lenses is that no one really wants them as a 400mm lens...everyone wants the verastility of using them with teleconverters to get the desired reach.
The EF 400mm f4 DO IS mkII is a VERY sharp lens. wide open natively and with a 1.4x TC it's pertty close to matching the EF mkIII f2.8 / RF version for sharpness and that's an increadible feat. Sure you loose a stop, but you are also shedding a lot of weight and size. It's a lens about the same mass as the EF 300mm f2.8 II LIS.

The issue with the EF 400mm DO IS II lens is when you are using 2x TC's and it really benefits from a 1/3rd of a stop down. Do this and it really bumps the sharpness up to the R5's resolving capability. it's probably not required for a R6II, it'll be sharp enough.

Comparing the 300 f2.8 mk II to the 400 DO mk II is really a choice beween needing a 300 that does TC's well (right up to 600mm) which over laps into the 400/f4 DO II's mastery. Or choosing a native 400 f4 DO II lens is a superior choice than the 300 f2.8 II LIS with a 1.4 TC. The 400 DO II is ligher, smaller and slightly sharper, as you would expect from a native lens vs a teleconverted lens.

With all of the lenses mentioned above, every one of them will probably out resolve 75% of the photographers who buy / use them. These lenes really need a tripod and great field craft to extract their very best. I've seen some truely insirational imagery from thes fine optics and some really shoddy stuff too.

 

[scyrene]

Ooft

 

[padam]

I am quite sure that these will make into production possibly in some further refined from, with the RF 400/4 DO 1.4x coming in earlier. (it will be much higher priced than a Z 400/4.5 and Z 600/6.3 PF, but it will handily compete with both)
And an RF 600/4 1.4x will be priced at least as much as the RF 800/5.6, which could be dropped together with the RF 600/4.
This will take a good few years though.

 

[GMCPhotographics]

So, looking back a the core of this thread....if this new patented optical formula actually translates into a real lens that is available to buy...what will be it's tangible benefits over the current EF 400mm DO mk II? Especially considering it's going to be an expensive new lens. Is it going to be even lighter? Is the flip in/out 1.4x TC it's only advantage? Is it going to be even sharper than the current mk II, which would reverse a recent RF white prime trend?
What would I get over a trade in of an existing superlative EF mkII lens apart from loosing a mssive pile of hard earned cash?

 

[Deleted member 378085]

Wonderful! Can't wait for this 600mm with tc to come out in 2135

 

[[email protected]]

...These lenes really need a tripod and great field craft to extract their very best. ...

Agree entirely on the fieldcraft. For the EF Mark II versions, a tripod probably. For the Mark III versions and the RF models, maybe not. Big weight differences. I think the EF III models are the best deal partly for this. They're light enough to get away hand-held, but much cheaper on the used market.

Most of my best shots forced me to find janky field stabilization, like pressing against a tree trunk, etc. Waiting for a critter to come to my tripod wouldn't get me as much. Biggest beef with tripods: they require me to move around the fulcrum of the tripod to line up the shot. That's enough movement to give me away often.

This mom bobcat was shot handheld at about 30 yards in early daylight (she was on a deer kill that she was reluctant to abandon). I knew her yearling kitten was somewhere nearby, as remote cameras indicated they were a constant pair, but I could only move my non-viewfinder eyeball to try to locate her. It's not a panning sort of situation. At the time, I thought it would have been handy to have had a monopod, as the staring contest went for a while. If I'd had a 600/800, I'd have taken both wide and long shots to mess with compositions later.

 

[john1970]

Wished the patent was for a 500 mm DO f4 with a built-in 1.4x TC. 400 mm is a bit too short for my needs.