# Patent: Canon EF 28-560mm f/2.8-5.6



## Canon Rumors Guy (May 20, 2016)

```
A patent for a super zoom optical formula from Canon has appeared. We heard a few months ago that Canon was <a href="http://www.canonrumors.com/new-superzoom-development-cr1/">working on a replacement</a> for the EF 28-300 f/3.5-5.6L IS. This optical formula is for a truly impressive EF 28-560mm f/2.8-5.6 super zoom. The likelihood of such a product? I’m not sure, as the lens would be quite large in size.</p>
<p>Patent Publication No. 2016-80973 (Google Translated)</p>
<ul>
<li>Published 2016.5.16</li>
<li>Filing date 2014.10.21</li>
<li>Zoom ratio 18.78</li>
<li>Focal length 28.80 139.49 540.91</li>
<li>F-number 2.88 4.77 5.88</li>
<li>Half angle of view (degrees) 36.91 8.82 2.29</li>
<li>Image height 21.64</li>
<li>The total lens length 298.13 341.13 398.13</li>
<li>BF 44.99 76.94 116.58</li>
</ul>
<p>I looked a few times to make sure this idea wasn’t for a smaller sensor PowerShot camera, which it isn’t. This is for a full frame DSLR.</p>
<span id="pty_trigger"></span>
```


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## East Wind Photography (May 20, 2016)

I would love something like this for video use. I use a sigma lens now but only works on aps-c cameras. I could use one of these for my 1dx mark ii. If it makes it to production, i hope its L standard.


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## Maui5150 (May 20, 2016)

Now this would be a fab lens if performance was even somewhat decent. Love the 2.8 on the short end


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## chrysoberyl (May 20, 2016)

There is no built-in extender? Sorry, I can't interpret optical patents well.


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## j-nord (May 20, 2016)

Talk about zoom ratio 

Is this the super zoom we've been hearing about? Are they really going to produce competitive IQ with that zoom ratio for under $2k?


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## Maximilian (May 20, 2016)

Looks like a very challenging optical formula. I wouldn't expect this to be great or decent over the whole FL. 
But if it was, it would be interesting for some out there. But also big and heavy.



chrysoberyl said:


> There is no built-in extender? Sorry, I can't interpret optical patents well.


No, no extender mentioned or included.
Here's my try to help you in interpretation (I hope, I don't blame myself too much  )


> Focal length 28.80 139.49 540.91 ==> focal length in mm at min., max. and somewhere in between
> F-number 2.88 4.77 5.88 ==> apertuere at min., max. and in between
> Half angle of view (degrees) 36.91 8.82 2.29 ==> field of view at min., max. and somwhere in between
> Image height 21.64 ==> height/radius of the image on image plane, showing if FF or APS-C or else 21.xy = FF and I think 16.xy = APS-C
> ...


So this lens will have a minimal mechanical length somewhere about 25 cm (298 - 45 mm).
And I suppose, it will be 30 to 50 % heavier than the recent 28-300L, so north 2 kg.
And aperture and focal length values are normally rounded, so f/5.88 will become f/5.6.


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## Fleetie (May 20, 2016)

Entrance pupil would have to be 560mm/5.6 = 100mm.

Doesn't that maybe slightly defeat the purpose of a super-zoom, whose raison d'etre is to be portable?

Don't get me wrong; I think I'd quite like such a lens.


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## neuroanatomist (May 20, 2016)

Size of a 300/2.8 when retracted, extends another 4" at full zoom. I think this one won't happen.


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## East Wind Photography (May 20, 2016)

neuroanatomist said:


> Size of a 300/2.8 when retracted, extends another 4" at full zoom. I think this one won't happen.



I think with the introduction of 4k video, Canon needs to introduce a superzoom that doesnt cost more than the 1dx mark ii. I really hope they can swing this for ar least the video market...and as such maybe doesnt have to have IQ close to the 600 f4L II.

There are not many lenses out there that have a decent range for video production. They are either for aps-c or cost above and beyond all reasonable sanity.


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## slclick (May 20, 2016)

Three Lenses for the Portrait-kings under the sky,
Seven for the Studio-lords in their halls of stone,
Nine for Mortal Men ******* to EF-S,
One for the Dark Lord on his D5,
In the Land of DR where the Shadows lie.
One Lens to rule them all, One Ring USM to find them,
One Lens to bring them all and in the darkness push them
In the Land of Canon where the Red Rings lie.


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## sjprg (May 20, 2016)

This is a lens I would buy. My 28-300 practically stays glued to my 5DSR. My only wish is that it could be 24mm on the wide end.


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## ahsanford (May 20, 2016)

.


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## ahsanford (May 20, 2016)

This one -- if it ever is built -- screams video more than anything else to me. A FF 20x zoom? Who on earth would use this for stills? 

Even the reach obsessed folks screaming for first-party 500mm+ options (other than a teleconverter or a trip to the bank for superwhite money) would not buy this. The IQ would be wretched, wouldn't it?

- A


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## Besisika (May 20, 2016)

East Wind Photography said:


> I would love something like this for video use. I use a sigma lens now but only works on aps-c cameras. I could use one of these for my 1dx mark ii. If it makes it to production, i hope its L standard.


I had the same thing in mind.
And then everybody will be intimidated when you point that thing at them.

I shot a concert once, the artist stopped in the middle of the song and asked everybody to applause the guy with a big white thing pointing at him. That was me with the 200 2.0


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## unfocused (May 20, 2016)

j-nord said:


> ...Are they really going to produce competitive IQ with that zoom ratio for under $2k?



No.


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## East Wind Photography (May 20, 2016)

unfocused said:


> j-nord said:
> 
> 
> > ...Are they really going to produce competitive IQ with that zoom ratio for under $2k?
> ...



Maybe for 8MP(4k) use, it doesnt have to have the same IQ. We lived without it for years before high mp sensors came out.


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## ahsanford (May 20, 2016)

unfocused said:


> j-nord said:
> 
> 
> > ...Are they really going to produce competitive IQ with that zoom ratio for under $2k?
> ...



J-nord, again, refer to my prior meme with Obi-Wan. The under-$2k long supertele we expect to see will be in the vein of the Nikon 200-500 f/5.6 VR for the amateur wildlife/birding crowd. Many threads have beaten up how Canon might do this, and the math and the money just gets thorny:


Zooming up to 600mm coupled with Canon's insistence on f/5.6 at the slowest (for the EF mount) kind of blows up the low-cost + front-filterable option. 600 / 5.6 = a very large entrance pupil.


Only going up to 500mm like Nikon did (wise for cost + filterability) may be passed over by the market for the three Tamron and Sigma 150-600mm options.



Given the cost of the 100-400L II, it's hard to see a 200-500 f/5.6L IS coming in under $2k, and I'm not convinced Canon will pull the L moniker off of the product and go plasticky/STM to keep it cheap. So I see more of a $3k lens than a $2k lens here. (I'm still waiting for proper reviews of the 200-500 Nikon to see what corners the designers cut to get that down to $1,400 -- at present, it seems like they are practically giving the lens away at cost to land-grab amateur birders all in a tizzy about the D500 ).

- A


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## Jack Douglas (May 20, 2016)

This thread has been great for a laugh. Love the humourists! 

We live in exciting times, indeed.

Jack


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## Don Haines (May 20, 2016)

It's true!

It really exists!

It has been field tested in Tokyo with a green covering to help disguise it.

Code name: GODZILLA!!!!!


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## ahsanford (May 20, 2016)

Don Haines said:


> It's true!
> 
> It really exists!
> 
> ...



Waaaaaay ahead of you...


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## TeT (May 20, 2016)

I don't know... I really like my all purpose zooms to be 24mm on the wide end... :


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## ahsanford (May 20, 2016)

TeT said:


> I don't know... I really like my all purpose zooms to be 24mm on the wide end...



If the 24-105L is a mess at 24mm, imagine what 24-560 would be! 

But I hear you. I'd be changing out a 28-something zoom so much more often than a 24-something zoom. Just a few millimeters, but it's tremendously useful. One has to wonder if that trend will continue... 20-70mm f/2.8L, anyone? 

- A


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## TeT (May 20, 2016)

for everyone wondering about the usefulness of this lens... same crowd as the 28 300 L.


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## RGF (May 20, 2016)

this lens would be huge. same diameter as the 300 F2.8.


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## j-nord (May 20, 2016)

ahsanford said:


> unfocused said:
> 
> 
> > j-nord said:
> ...


It was a rhetorical question  It seems highly unlikely they'd make a FF lens with this spec regardless of price or performance.

p.s. I posted before your meme 8)


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## lol (May 20, 2016)

Checking date... not 1st April. Ok, I'm up for this.


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## KeithBreazeal (May 20, 2016)

Well, this is going to totally suck. I'll only need one lens/body on the black rapid. I'll need a 20 pound block of lead attached to the other strap for balance. Need to start the weight training program again.


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## Jack Douglas (May 20, 2016)

RGF said:


> this lens would be huge. same diameter as the 300 F2.8.



This lens would be F2.8 at what focal length - not 300? So does it have to be the size of a 300 2.8?

Jack


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## davidmurray (May 20, 2016)

Besisika said:


> East Wind Photography said:
> 
> 
> > [snip]
> ...



Snipped quotes for brevity.
I too was buy one of these - if the IQ was good enough across the whole range.

I would expect people to be intimidated if you're pointing a Canon at them with the intention of shooting. :


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## Ozarker (May 20, 2016)

j-nord said:


> Talk about zoom ratio
> 
> Is this the super zoom we've been hearing about? Are they really going to produce competitive IQ with that zoom ratio for under $2k?



Under $2K? Why nawwwww.


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## Ozarker (May 20, 2016)

KeithBreazeal said:


> Well, this is going to totally suck. I'll only need one lens/body on the black rapid. I'll need a 20 pound block of lead attached to the other strap for balance. Need to start the wight training program again.



You could carry it low and directly in the front as subliminal suggestion.


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## KeithBreazeal (May 20, 2016)

CanonFanBoy said:


> KeithBreazeal said:
> 
> 
> > Well, this is going to totally suck. I'll only need one lens/body on the black rapid. I'll need a 20 pound block of lead attached to the other strap for balance. Need to start the wight training program again.
> ...



LOL! Is that a Canon or are you happy to see me?


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## applecider (May 20, 2016)

j-nord said:


> Talk about zoom ratio
> 
> Is this the super zoom we've been hearing about? Are they really going to produce competitive IQ with that zoom ratio for under $2k 4K. 5k?



There fixed that for you.


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## GMCPhotographics (May 20, 2016)

The objective lens is going to be quite large, minimum 96mm in diameter. So it's unlikely to be a cheap lens. The other thing that struck me was....why the odd focal length...560mm??? Where did that come from?


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## H. Jones (May 20, 2016)

GMCPhotographics said:


> The objective lens is going to be quite large, minimum 96mm in diameter. So it's unlikely to be a cheap lens. The other thing that struck me was....why the odd focal length...560mm??? Where did that come from?



400mm with a 1.4 extender is 560mm, not sure if that has any effect, but it's a prominently used focal length for that reason. If this doesn't have a built in extender, which it looks like it doesn't have one, I'm guessing it was a compromise for size reasons. 560 / 5.6 = 100, might have to do with the objective lens diameter, but I'm not too well versed in lens design.


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## ahsanford (May 20, 2016)

kraats said:


> I will be glad to sell my 24-70 II, 70-200 IS 2.8 II and my 100-400 II for this lens if it is any good.



*You* might happy, but your back won't be. 

- A


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## Wizardly (May 20, 2016)

Interestingly all four working examples describe the same type of lens. 
The aberration graphs are not as abysmal as one might expect. At 300 mm in total length this is fairly comparable to the other super telephoto zooms already on the market.
There is also at least a superficial resemblance to the Tamron 16-300 mm APSC lens. This lens may be a stepping stone or derivative design of a Canon cropped superzoom.


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## can0nfan2379 (May 20, 2016)

slclick said:


> Three Lenses for the Portrait-kings under the sky,
> Seven for the Studio-lords in their halls of stone,
> Nine for Mortal Men ******* to EF-S,
> One for the Dark Lord on his D5,
> ...



That right there is pure awesome.


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## can0nfan2379 (May 20, 2016)

ahsanford said:


> .



Also awesome!


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## Wizardly (May 21, 2016)

GMCPhotographics said:


> The objective lens is going to be quite large, minimum 96mm in diameter. So it's unlikely to be a cheap lens. The other thing that struck me was....why the odd focal length...560mm??? Where did that come from?





560mm is a number Egami made up. The patent specifies 540mm

Check my math, but in WE1, the first element has a thickness of 1.90366 mm with a radius of curvature of 230.39mm and 114.55mm; this would put the diameter at around 60mm.


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## Don Haines (May 21, 2016)

bah... superzooms.... non "L" lenses.... a photographer craves not these things.....


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## Mt Spokane Photography (May 21, 2016)

Small is relative, but it has been possibile to minimize lens size for consumer lenses where they were not built like a tank. The patent refers over and over to small lens size, below are a couple of quotes.

So... I could just leave it attached to a SL-1 and carry it around in my camera bag ;D

From the Patent

"In recent years, the imaging optical system used for an imaging device is required to be a highly efficient zoom lens by the high zooming ratio, though the whole system is small. It is requested that a focus is made to these zoom lenses at high speed and with high precision etc."

"The present invention aims at offer of the imaging device which has the small zoom lens and it from which a quick focus is easy, and it is a high zooming ratio, and high optical performance is obtained covering the object distance all the zoom ranges and at large."

_*And --- Its a Macro Lens too:*_

"the miniaturization of the whole lens system becomes easy. *Close photographing, especially pole close photographing become easy*. Since the small lightweight lens group is moved, the driving force of a lens group is small, and ends, and there are the characteristics, like a quick focus is made."


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## RGF (May 21, 2016)

Jack Douglas said:


> RGF said:
> 
> 
> > this lens would be huge. same diameter as the 300 F2.8.
> ...



The diameter of the front element is (approximately) the focal length divided by the aperture.

Thus a 560 / 5.6 = 100mm. A 300 /2.8 ~ 100mm. Same diameter.

The definition of the F stop is the focal length of the lens divided by the maximum diameter of the aperture when opened fully.


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## sjprg (May 21, 2016)

Well the 28-300 goes for ~$2400+USD so probably in the $3500-$4000 range.


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## Mt Spokane Photography (May 21, 2016)

sjprg said:


> Well the 28-300 goes for ~$2400+USD so probably in the $3500-$4000 range.



You are assuming a "L" lens. Its likely a consumer lens to compete with the Tamron and Sigma lenses.


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## JJF (May 21, 2016)

I would buy this lens.


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## TAF (May 21, 2016)

Mt Spokane Photography said:


> sjprg said:
> 
> 
> > Well the 28-300 goes for ~$2400+USD so probably in the $3500-$4000 range.
> ...



Perhaps the kit lens for a future 6D3?


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## Wizardly (May 21, 2016)

RGF said:


> Jack Douglas said:
> 
> 
> > RGF said:
> ...



Not exactly. The f stop is the focal length over the entrance pupil diameter, not the actual aperture diameter. The entrance pupil is the image of the aperture from the objective side; it is the image of the opening that can be magnified by the optics.


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## privatebydesign (May 21, 2016)

Wizardly said:


> RGF said:
> 
> 
> > Jack Douglas said:
> ...



I'd argue the f stop is the focal length over the apparent size of the entrance pupil diameter. But even if we quibble over technicalities the optical fact remains that the aperture can't be larger than the front element because it can't appear to be bigger than that, ergo the focal length divided by aperture will give you a minimum front element size. 

If you can point me to a lens that has a front element smaller than its focal length divided by its actual fastest aperture I'd like to see it.


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## dash2k8 (May 21, 2016)

I see no reason for such a lens to exist unless Canon has found a magical new design method to ensure superb image quality throughout this zoom range. And if that really did happen, this lens would cost too much. The old 28-300 was a dud. Will this be any better? We'll have to see.


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## Steve Dmark2 (May 21, 2016)

Why are only the zoom updated? :'(
With such a lens you just carry around more kilos.

Common canon.
I would like to see much more the update of 300mm 4l IS or 400mm 5.6L to IS.


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## neuroanatomist (May 21, 2016)

dilbert said:


> The 28-300 is a 10x zoom. The 28-560 is a 20x zoom.



What a pithy remark. Are you trying to demonstrate that you can sort of do math, and sometimes get a correct answer?


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## Don Haines (May 21, 2016)

neuroanatomist said:


> dilbert said:
> 
> 
> > The 28-300 is a 10x zoom. The 28-560 is a 20x zoom.
> ...



A 28-300 is a 10.7X zoom  Are you trying to demonstrate that you can't do math   

Come on Neuro..... this is overkill.... You don't have to pick on everything he posts.... you are better than this.


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## neuroanatomist (May 21, 2016)

Don Haines said:


> neuroanatomist said:
> 
> 
> > dilbert said:
> ...



And a 28-560mm is a 20x zoom.  Are you trying to demonstrate the definition of the word 'sometimes'?   

Actually, a 50% correct rate is better than average in this case.


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## Don Haines (May 21, 2016)

Tamron makes a 16-300mm (18.8X) zoom lens for crop cameras. It is a very popular lens and sells quite well. Although the image quality suffers with such a wide range, for many people the convenience of just having the single lens seems to out-weigh the drop in IQ.

Now a 20X zoom? ? ? about the same ratio so it can obviously be done without killing the IQ..... but here we are talking about 560mm at the far end instead of 300m, and we are talking about F5.6 instead of F6.3. This will be a large heavy beast and that is going to mitigate a lot of the convenience of having a single lens. For example, I have the Tamron 150-600 and that should be roughly the physical size of this lens (actually a touch smaller) and as an 188cm tall person who carries canoes through the woods I find it to be a heavy and awkward lens. This isn't a walk-around-all-day-with-it-hanging-off-the-camera-strap kind of lens, and that is going to limit the market of potential buyers....

In the end, I think that this is a "look what I can do" type of product and will never see the mass market.


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## Don Haines (May 21, 2016)

neuroanatomist said:


> Don Haines said:
> 
> 
> > neuroanatomist said:
> ...


and a 50% correct rate beats weather forecasters, who are wrong 117% of the time.....


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## Jack Douglas (May 21, 2016)

Not to mention the global climate forecasters?

Neuro, I'm curious if this is a gradual long term disdain or has there been a specific issue. In roughly a couple years plus, I get the gist of the problem, but why so persistent? It would strike me that a response is a waste of energy that could be directed elsewhere. The correction of misguided information is valuable but .....

Jack


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## GMCPhotographics (May 21, 2016)

RGF said:


> Jack Douglas said:
> 
> 
> > RGF said:
> ...



Yes it's a general rule which I use too...but this isn't a 560mm...the patent is for a 540mm. Which brings the objective lens down a bit to 96mm. 
If we are looking at a lens with an approximate from element of say 100mm...this lens isn't going to be much cheaper than the current 300mm f2.8 LIS II. I also don't understand the need for another 200-400 +integrated 1.4x TC lens...that's already covered very well with the 200-400 LIS. 
I suspect that this is a 28-540mm f5.6-f8 lens. Giving a front optic of around 67mm and making it squarely in the consumer market.


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## neuroanatomist (May 21, 2016)

GMCPhotographics said:


> I suspect that this is a 28-540mm f5.6-f8 lens. Giving a front optic of around 67mm and making it squarely in the consumer market.



A lens for the consumer market which will not AF (live view notwithstanding) on the vast majority of Canon dSLRs used in the consumer market? I don't think that's a viable option.


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## Wizardly (May 21, 2016)

privatebydesign said:


> Wizardly said:
> 
> 
> > RGF said:
> ...



The patent gave the dimensions of the front element. 1.9 mm thick with curvature radii of 114 mm on the front and 230 mm on the back. The front element should only be 60mm, no?

I'm trying to understand this phenomenon myself, but conceptually I understand it to mean that the elements in front of the aperture are causing the rays to converge towards the aperture so that the image of the aperture is larger than the front element; if you were trying to see the aperture you would have to angle the lens away from your eye to see the edge.


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## nvsravank (May 21, 2016)

Wizardly said:


> privatebydesign said:
> 
> 
> > Wizardly said:
> ...


Wouldn't that mean a significant vignette ?
Also I have been searching on and off all morning to find a lens that does what you say. Can you point out actual production lens? Like private by design asked. I am unable to find it. Google is not being my friend. 

But this topic has been good for me to learn some obscure/abstruse facts and came to read about front pupil and back Pupil. 

Any way to set the aperture of electronic lenses to see this in action?


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## mb66energy (May 21, 2016)

A lens with the radii and max thickness you mentioned has -- if both are convex -- a diameter of 34 mm and if the inner radius is concave, the outer one convex you will have the diameter of maximal 58mm -- but the thickness is then zero on the outside! Both lenses were positive.
If both radii describe concave surfaces 200mm diameter are possible (but pure nonsense I think) and the lens is negative.

Strange.



Wizardly said:


> privatebydesign said:
> 
> 
> > Wizardly said:
> ...


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## Wizardly (May 21, 2016)

nvsravank said:


> Wizardly said:
> 
> 
> > privatebydesign said:
> ...



It just happens that I have a Quantaray (Tamron) 70-300 collecting dust in a closet that, when fully telephoto and focused all the way in has an entrance pupil that is larger than the front element.


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## sjprg (May 21, 2016)

Whomever it was that called the 28-300 a dud, was a dunce. The lens does a great job and I hope the new 28-540 is an "L" lens that I can carry for another 10 years.


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## Mt Spokane Photography (May 21, 2016)

sjprg said:


> Whomever it was that called the 28-300 a dud, was a dunce. The lens does a great job and I hope the new 28-540 is an "L" lens that I can carry for another 10 years.



The 28-300 is a great lens for what it does. But, carrying it everywhere is something I found to be impractical. 

Personally, I expect this lens to be seriously considered by Canon. They seem to try and outdo the competition. It would be difficult to make a affordable lens better than the Sigma or Tamron super tele lenses, so they will go one step further. With Nikon now having a consumer grade super telephoto lens, Canon will try to outdo them all.

If such a lens were close focusing as they indicate, it might be a favorite for small birds too.


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## Wizardly (May 21, 2016)

mb66energy said:


> A lens with the radii and max thickness you mentioned has -- if both are convex -- a diameter of 34 mm and if the inner radius is concave, the outer one convex you will have the diameter of maximal 58mm -- but the thickness is then zero on the outside! Both lenses were positive.
> If both radii describe concave surfaces 200mm diameter are possible (but pure nonsense I think) and the lens is negative.
> 
> Strange.



Outer surface is convex, inner surface is concave. The front group is a doublet.


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## mb66energy (May 22, 2016)

Wizardly said:


> mb66energy said:
> 
> 
> > A lens with the radii and max thickness you mentioned has -- if both are convex -- a diameter of 34 mm and if the inner radius is concave, the outer one convex you will have the diameter of maximal 58mm -- but the thickness is then zero on the outside! Both lenses were positive.
> ...



So we have a maximum of 58mm resulting in ca. f/10 - strange.

You mentioned a lens with larger entrance pupil than front lens element ...? If you "believe" in energy conservation this isn't possible: The front lens open diameter determines the area where light can pass into the lens and onto the sensor. This is THE LIMIT. Perhaps it is some visual effect which is more dramatic during zooming a lens?


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## privatebydesign (May 22, 2016)

Wizardly said:


> nvsravank said:
> 
> 
> > Wizardly said:
> ...



Care to elaborate on that? What lens, how did you determine the entrance pupil size etc etc?


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## Wizardly (May 22, 2016)

mb66energy said:


> So we have a maximum of 58mm resulting in ca. f/10 - strange.
> 
> You mentioned a lens with larger entrance pupil than front lens element ...? If you "believe" in energy conservation this isn't possible: The front lens open diameter determines the area where light can pass into the lens and onto the sensor. This is THE LIMIT. Perhaps it is some visual effect which is more dramatic during zooming a lens?



I'm having a hard time conceptualizing this myself given the geometry. Also, for specificity, the f number is 5.88, not 5.60; we're looking at 540.91mm/5.88 = 91.99 mm.


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## Wizardly (May 22, 2016)

privatebydesign said:


> Care to elaborate on that? What lens, how did you determine the entrance pupil size etc etc?



I will absolutely defer to the smarter in this regard. If I'm misunderstanding the phenomenon please let me know. If you set a lens with a 62mm front element wide open and stand "infinitely" far away and cannot see the edge of the entrance pupil looking down optical axis unless you angle off from the optical axis, does that mean that the entrance pupil is larger than the front element itself?

I'm really struggling to understand how a lens with a 92mm entrance pupil can have a front element that is only around 60mm in diameter given the geometry specified in the patent.


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## pierlux (May 22, 2016)

GMCPhotographics said:


> ...but this isn't a 560mm...the patent is for a 540mm. Which brings the objective lens down a bit to 96mm. ... ...



The patent also indicates F-number = 5.88 at the long end, resulting in a 92mm front element by the same math. "Narrow" enough to accomodate 95mm filters. Or no filter thread at all, but a drop-in holder and built-in hood in which case this could be an "L" lens.

If this patent really represents the rumored supertelephoto zoom, the one I and others are waiting from Canon, the one which is intended to smack the Nikon/Sigma/Tamron offerings, then I don't know what to say.

A part of me, the rational one, is disappointed because I'd want something optically outstanding at the long end to the point that I'd prefer a supertelephoto prime over the zoom option and I really don't know how a 20x zoom could be optically outstanding.

Another part of me, the irrational and optimistic one, is excited because, as for the latest Canon releases, it can't be at least on par with, or superior to, its competitors IQ-wise and the extreme zoom range could help Canon sell more units and therefore help keep the price lower than most imagine. Maybe as low as $ 3-3.5K. Yes I know, lots of talk already about the price in past threads, but how is it otherwise possible to compete with $ 1.5-2K offerings?


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## privatebydesign (May 22, 2016)

Wizardly said:


> privatebydesign said:
> 
> 
> > Care to elaborate on that? What lens, how did you determine the entrance pupil size etc etc?
> ...



You can't put your camera " _"infinitely" far away_ ". You can only measure the apparent entrance pupil size from the point of focus, in this case where the sensor would be.

I haven't seen the block diagram/patent but it isn't possible to have a 92mm entrance pupil and a 60mm front element.


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## privatebydesign (May 22, 2016)

I just looked at the patent. 

It is an f5.88 at 540.91mm, so would require a minimum 92mm front element. The patent lists the front element diameter as 109.04mm (_"The effective diameter of the front lens 109.04mm"_).

No mystery, no laws of optics and physics broken, just normal internet nonsense 

Incidentally, if this became reality it would command an astronomic price, it is vastly more complex than a 300 f2.8 and has a similar sized front element. Current B&H 300mm price $6,099.

My guess would be if it covered a FF sensor that it would be a CN lens for video use and be aimed/positioned for 4k and 8k capture.


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## Wizardly (May 22, 2016)

privatebydesign said:


> I just looked at the patent.
> 
> It is an f5.88 at 540.91mm, so would require a minimum 92mm front element. The patent lists the front element diameter as 109.04mm (_"The effective diameter of the front lens 109.04mm"_).



*smacks forehead* must have gotten too used to the patents not explicitly stating the ED that I never even noticed. Also realize I had the radii on the wrong side and that convergence was never to occur. If you'll excuse me I'll be double checking all other equations for the last few days.....


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## privatebydesign (May 22, 2016)

Wizardly said:


> privatebydesign said:
> 
> 
> > I just looked at the patent.
> ...



 No worries, we all have days like that! (I certainly do..........)


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## neuroanatomist (May 22, 2016)

Well, it seems the laws of physics are safe again...at least for now.


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## quiquae (May 22, 2016)

One reason why I suspect this lens is never going to hit the market: *no IS*.

Canon has not released a new lens more than 85mm long without IS since 2007 (800L).


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## privatebydesign (May 22, 2016)

quiquae said:


> One reason why I suspect this lens is never going to hit the market: *no IS*.
> 
> Canon has not released a new lens more than 85mm long without IS since 2007 (800L).



Oh yes they have.

https://en.m.wikipedia.org/wiki/Canon_Cinema_EOS

Now if we consider the fact that Canon are pushing hard with the R&D on 8k, is it unreasonable to think they are going to want wider than Super 35 coverage of the current CN-E zoom lenses? How about the 4k DCI footage from the 1DX MkII and 1DC, both of which are wider than the CN-E zoom coverage so far.


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## scyrene (May 22, 2016)

privatebydesign said:


> Wizardly said:
> 
> 
> > RGF said:
> ...



Playing devil's advocate... the MP-E maybe?


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## privatebydesign (May 22, 2016)

scyrene said:


> privatebydesign said:
> 
> 
> > Wizardly said:
> ...



You devil you!

But no, the MP-E 65 doesn't break any laws of optics either. This is the best image I could find of one from the front. If the outer two lines are 58mm apart, which they should be close to, then the inner lines are 24mm apart, 65mm / f2.8 = 23.2.


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## neuroanatomist (May 22, 2016)

privatebydesign said:


> scyrene said:
> 
> 
> > Playing devil's advocate... the MP-E maybe?
> ...



Not to encourage sympathy for the devil, but your careful estimate based on an image from the Internet notwithstanding, empirically measuring my own MP-E 65mm shows that the front element diameter is ~19.5mm.


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## privatebydesign (May 22, 2016)

neuroanatomist said:


> privatebydesign said:
> 
> 
> > scyrene said:
> ...



Interesting, and thanks for the actual measurement.

Which leads us to conclude that either Canon have broken the laws of optics and kept it very quiet, or the MP-E65 isn't a true 65mm and f2.8. 

Personally I believe the latter


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## hne (May 23, 2016)

privatebydesign said:


> Wizardly said:
> 
> 
> > privatebydesign said:
> ...



Can you see an elephant while you're wearing glasses? The whole elephant at once through 30mm diameter lenses?

You can see an entrance pupil appearing 92mm in diameter through a 60mm front element if you depart from the thin lens assumption so you are able to place the aperture somewhere in-between the front element and the sensor and place yourself close enough to the front element.

So yes, the MP-E 65 can have a 19.5mm front element through which an entrance pupil seemingly 23.2mm wide can be seen, as long as you place your eye rather close to the front element and the aperture is placed some distance from the front element.


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## scyrene (May 23, 2016)

privatebydesign said:


> neuroanatomist said:
> 
> 
> > privatebydesign said:
> ...



Haha, if there's one lens guaranteed to muddy the waters... I'm sure you're right though  I rather wonder what 65mm really means for a lens like this. I mean, normal lenses you can compare in terms of focal length and have an idea of field of view, and for macro lenses that still focus to infinity, the working distance at 1:1 . But this one is so odd, it seems redundant giving it a focal length designation (to me).


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## neuroanatomist (May 23, 2016)

hne said:


> Can you see an elephant while you're wearing glasses? The whole elephant at once through 30mm diameter lenses?
> 
> You can see an entrance pupil appearing 92mm in diameter through a 60mm front element if you depart from the thin lens assumption...



Ironic that your analogy much more closely approximates a thin lens.  It's not relevant, though, given the position of eyeglasses in relation to the biological optics. 

In this case, *scyrene* is looking in the right place – 'focal length' is the distance from the image plane to the apparent position of the entrance pupil _when the lens is focused at infinity_. The design of the MP-E precludes infinity focus, so the 65mm focal length is a theoretical not a real measurement, i.e. the FL _would be_ 65mm _if_ the lens could focus at infinity. It can't, so the actual focal length is shorter. Ignoring rounding of the aperture value, f/2.8 with a 19.5mm front element would be a max FL of 55mm. In fact, the actual FL with the focus racked out as far as possible is probably even shorter. As an example, the FL of the 100/2.8 Macro is 100mm focused at infinity, but ~67mm at 1:1.


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## scyrene (May 24, 2016)

neuroanatomist said:


> hne said:
> 
> 
> > Can you see an elephant while you're wearing glasses? The whole elephant at once through 30mm diameter lenses?
> ...



Eureka! This is very well explained, thanks


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## neuroanatomist (May 24, 2016)

scyrene said:


> Eureka! This is very well explained, thanks



Well, you know, it'd still be cool if Canon had figured out how to get around the laws of physics.


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## East Wind Photography (May 24, 2016)

neuroanatomist said:


> scyrene said:
> 
> 
> > Eureka! This is very well explained, thanks
> ...



They are trying with all of that blue stuff in the mix. I hear they are tinkering with dynamic lens elements that can change shape and FL when an electrical signal is applied.


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## mb66energy (May 25, 2016)

neuroanatomist said:


> hne said:
> 
> 
> > Can you see an elephant while you're wearing glasses? The whole elephant at once through 30mm diameter lenses?
> ...



How do you have measured the FL of the 100mm or do you have some source of people who measured the FL? 

My internal conflict is: The EF 100 (non-IS) needs a 4 times increase of the exposure time between infinitity and 1:1 which is conformal to a lens(group) of 100mm FL over the whole focusing range. While the MP-E 65 is sth. like a zoom where zooming is used to focus.
I alway thought the EF 100 Macro and EF-S 60 Macro are lenses which shift principal planes optically to simulate the shifting of a 100mm lens (having a fixed lens arrangement).

Would be great to have some additional info about that - Best, Michael


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