# Canon EF 100-400 f/4-5.6L IS Patent Pending



## Canon Rumors Guy (Sep 20, 2011)

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<div id="attachment_7187" class="wp-caption aligncenter" style="width: 327px"><img class="size-full wp-image-7187" title="100400patentnew" src="http://www.canonrumors.com/wp-content/uploads/2011/09/100400patentnew.png" alt="" width="317" height="206" /><p class="wp-caption-text">New 100-400 f/4-5.6L IS Optical Design</p></div>
<strong>New 100-400 f/4-5.6L IS in the pipeline?

</strong>A pending patent has shown up showing a new 100-400 optical design. This new design seems to suggest better optical performance as well as starting at f/4.</p>
<div id="attachment_7188" class="wp-caption aligncenter" style="width: 410px"><img class="size-full wp-image-7188" title="100400patentoriginal" src="http://www.canonrumors.com/wp-content/uploads/2011/09/100400patentoriginal.png" alt="" width="400" height="270" /><p class="wp-caption-text">Current 100-400 f/4.5-5.6L IS Optical Design</p></div>
<p><strong>Patent Publication No. 2011-180218</strong></p>
<ul>
<li>2011.9.15 Release Date</li>
<li>Filing date 2010.2.26</li>
</ul>
<p><strong>Example 1</strong></p>
<ul>
<li>Focal length f = 72.20 â€“ 135.00 â€“ 290.00mm</li>
<li>Fno = 4.20 â€“ 4.67 â€“ 5.86</li>
<li>Half angle of 16.68 â€“ 9.10 â€“ 4.27 Ã‚Â°</li>
<li>Image height 21.64mm</li>
<li>Lens length 185.20 â€“ 214.53 â€“ 239.20mm</li>
<li>Back Focus 46.74 â€“ 47.82 â€“ 57.41mm</li>
<li>4.02x zoom ratio</li>
<li>Group 6 for each group</li>
<li>Positive and negative polarity positive or negative group configuration</li>
</ul>
<p><strong>Example 2</strong></p>
<ul>
<li>Focal length f = 102.20 â€“ 200.00 â€“ 390.01mm</li>
<li>Fno = 4.10 â€“ 4.55 â€“ 5.90</li>
<li>Half angle of 11.95 â€“ 6.17 â€“ 3.18 Ã‚Â°</li>
<li>Image height 21.64mm</li>
<li>Lens length 228.18 â€“ 258.83 â€“ 288.12mm</li>
<li>Back Focus 51.23 â€“ 54.42 â€“ 69.84mm</li>
<li>3.82x zoom ratio</li>
<li>Group 6 for each group</li>
<li>Positive and negative polarity positive or negative group configuration</li>
</ul>
<p><strong>Example 3</strong></p>
<ul>
<li>Focal length f = 100.20 â€“ 135.10 â€“ 290.19mm</li>
<li>Fno = 4.36 â€“ 4.47 â€“ 5.81</li>
<li>Half angle of 12.18 â€“ 9.10 â€“ 4.26 Ã‚Â°</li>
<li>Image height 21.64mm</li>
<li>Lens length 184.66 â€“ 198.82 â€“ 244.82mm</li>
<li>Back Focus 42.53 â€“ 46.68 â€“ 63.07mm</li>
<li>2.90x zoom ratio</li>
<li>5 groups, each group</li>
<li>Positive and negative group of negative polarity configuration</li>
<li>Positive-lead type zoom lens</li>
<li>High zoom ratio can be easily realized</li>
<li>Rear Focus</li>
<li>Can be miniaturized</li>
<li>Easy full-time manual</li>
<li>Suppressing the fluctuation of spherical aberration</li>
<li>Upon zooming, if you move from behind the eyes, counting the two groups, the greater the variation of spherical aberration in the focusing</li>
<li>On-axis beam angle ÃŽÂ¸ the following equation:</li>
<li>ÃŽÂ¸ = AISN (1 / 2 * Fno)</li>
<li>Spherical aberration is proportional to the fourth power of the high on-axis ray</li>
<li>In focusing heavily on the object side to move first, counting from one group behind, which varies significantly higher on-axis ray</li>
<li>Canonâ€™s patents, and by fixing the first two groups, counting from the back of the eye movement to limit the amount counted from the first team back, suppressing the fluctuation of spherical aberration</li>
</ul>
<div><strong>via [<a href="http://egami.blog.so-net.ne.jp/2011-09-16">EG</a>]</strong></div>
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## GMCPhotographics (Sep 20, 2011)

Can someone knowledgable please explain the three examples? Surely these are three different lenses? A 70-300, a 100-400 and a 100-300. Is this correct?


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## adhocphotographer (Sep 20, 2011)

there is already 3 70-300's and a 100-300 would just be overlap... 100-400 update would be great... how long it will take to see the light of day is a completely different story!


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## Forceflow (Sep 20, 2011)

This is certainly interesting. I do need a long lens and the 100-400 was one that I was looking at. A Mark II version of that one would be nice, especially if it turns out to be a bit faster as well.


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## J. McCabe (Sep 20, 2011)

Why is the image height 21.64mm ?

Is it because those are APS-C lenses, or because that's half the radius required to cover an FF sensor ?


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## smirkypants (Sep 20, 2011)

Can we please just get a 200-400 f/4 zoom? Please? Before I go buy a Nikon? I'd really like to be able to take a decent photo at 400mm when skies are gray without being stuck with a prime. Thanks Canon.


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## Mihast (Sep 20, 2011)

GMCPhotographics said:


> Can someone knowledgable please explain the three examples? Surely these are three different lenses? A 70-300, a 100-400 and a 100-300. Is this correct?



Contrary to polular beleive, patents are not granted to specific lenes designs but to solutions of optical problems (see claims section of patents or patent applications). Examples that demonstrate said solutions are of course more interesting to general public as they demonstrate (more or less) practical lenses and some of them may even see production.


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## neuroanatomist (Sep 20, 2011)

J. McCabe said:


> Why is the image height 21.64mm ?
> 
> Is it because those are APS-C lenses, or because that's half the radius required to cover an FF sensor ?



I'd assume it's the radius of the image circle (not half the radius, since the radius is already half the diameter). EF lenses have a 43.2 mm diameter image circle, and 2 x 21.64 mm = 43.3 mm.


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## Meh (Sep 20, 2011)

Mihast said:


> Contrary to polular beleive, patents are not granted to specific lenes designs but to solutions of optical problems (see claims section of patents or patent applications). Examples that demonstrate said solutions are of course more interesting to general public as they demonstrate (more or less) practical lenses and some of them may even see production.



Exactly correct. In addition, it's not a given that Canon (or any other lens designer) would file patents for a new design only if it is an improvement. They might even file a patent they have no intention of ever using. Their designers are working all the time and let's say they come up with a new design that is almost as good as their current design. They might file the patent to prevent say Sigma from using it to market a lens that is seen as almost as good as the Canon but lower price.


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## AJ (Sep 20, 2011)

I suppose another way to look at this is that a 100-400 mk2 isn't just around the corner. It's still early in its development phase.


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## ecka (Sep 20, 2011)

May I ask for EF 100-300/4L IS USM, please : Canon? Which you should have made instead of 70-300L.
What? Come back in 2021? O.K. I'll wait, thank you. See you later.

P.S. lol


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## kubelik (Sep 20, 2011)

I have no idea how to read patents so ... can anyone tell if this would still be a push-pull design? rotating zoom would be much preferred ... although frankly, with the 2X on the 70-200 f/2.8, I'm not really in the market for a repeat lens in this range.


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## lol (Sep 20, 2011)

smirkypants said:


> Can we please just get a 200-400 f/4 zoom? Please?


They announced it a while ago... only a matter of time before it's in production. Someone more geeky than me might be able to say how long a typical delay is between announcement and production release.



kubelik said:


> I have no idea how to read patents so ... can anyone tell if this would still be a push-pull design?


I think this is only for the optical formula, and nothing to do with the build.


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## Dave (Sep 20, 2011)

Despite the push/pull design... what's so bad about the current 100-400ÃŸ?


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## lol (Sep 20, 2011)

It doesn't matter if you have the best there is. Someone will still want "better".

Specifically on a hypothetical 100-400L II, I think the most significant changes will be in areas other than the basic optics. The push-pull vs. twist argument will probably go on forever but at the end of the day you get what you're given or look elsewhere. Updated IS would be a given, and I'd expect a weather sealing upgrade too. If the optics are improved on top of that, I don't think there's much to complain about other than the price tag.


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## bvukich (Sep 20, 2011)

Dave said:


> Despite the push/pull design... what's so bad about the current 100-400ÃŸ?



It's first gen IS system could stand an update, and coatings/etc. etc are always getting better. But it is already an outstanding lens, there are quite a few other lenses that are more needing of an update.


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## photophreek (Sep 20, 2011)

I agree with DAVE, there is nothing wrong with the current 100-400mm. I just bought one and the IQ/sharpness is quite amazing. I'd say it's on par with my 400mm f/5.6. The push/pull zoom does require some getting used to, but certainly not a deal breaker.

I've worked filing and defending patents. The big problem is defending patents. These patents were probably filed to protect the design and does not mean that a ver II will come out anytime soon.


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## Mt Spokane Photography (Sep 20, 2011)

kubelik said:


> I have no idea how to read patents so ... can anyone tell if this would still be a push-pull design? rotating zoom would be much preferred ... although frankly, with the 2X on the 70-200 f/2.8, I'm not really in the market for a repeat lens in this range.



After reading thru the entire patent, I would say that its probably a push-pull. 5 lens groups move foward while zooming while the 6th and rearmost group moves only with the focus ring to focus. Typically, rotating zoom rings only move some of the elements while others are fixed. You can, of course design it as a rotating zoom ring, bit it doesn't sound practical to move the first 5 lens groups a large distance.


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## dstppy (Sep 21, 2011)

photophreek said:


> I agree with DAVE, there is nothing wrong with the current 100-400mm. I just bought one and the IQ/sharpness is quite amazing. I'd say it's on par with my 400mm f/5.6. The push/pull zoom does require some getting used to, but certainly not a deal breaker.
> 
> I've worked filing and defending patents. The big problem is defending patents. These patents were probably filed to protect the design and does not mean that a ver II will come out anytime soon.


"won't come out soon" -- definitely agree . . .

But if you read through pretty much every one of "Roger's Take"s on LensRentals.com, you'll see that nothing wrong doesn't mean a better lens won't come out. (Depends on how much you're REALLY trying to avoid actual work). Canon has had some darned good lenses that it released a "II" version of and had marked improvement . . . so it's never say never.

Besides, releasing an even better version of an excellent lens means that the previous version is 'worth less' than it was before, used  *IF* Canon ever did release a MkII of the 100-400, I think it would be a home-run . . . it wouldn't be worth it otherwise, no?


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## Mt Spokane Photography (Sep 21, 2011)

I certainly love my 100-400mm L, if a reasonably priced upgrade were to appear, I'd want it. However, the 70-200mm L MK II jumped $800 or more when it appeared, so I'd expect the same here.


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## /dev/null (Sep 21, 2011)

I know well that (a) this does not prove that a new lens is around the corner and (b) it is supposed to be a more or less general solution to an optical problem rather than a specific lens design.
Having said that, the arrangement does look rather similar to the existing 100-400L, so it would appear that this is not some land-grab of a far-future crazy idea but something rather practical and therefore much closer to production. 
The 100-400 is certainly a good candidate for that. There has already been plenty of speculation about an replacement. I don't know how long patents take to get approved and published these days, but if a factory-ready design existed, Canon would certainly hold it back until the patent was published.


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## Lee Jay (Sep 22, 2011)

Dave said:


> Despite the push/pull design... what's so bad about the current 100-400ÃŸ?



Really poor handling in multiple ways, poor performing IS, optical quality degrades a lot if the IS happens to be at a substantially off-center position when you shoot, mediocre corner performance, relatively slow AF compared to newer lenses, not diffraction-limited in the center wide open despite being f/5.6.

I'd really, really, really like to see a new high-pixel-density 1.6-crop camera with high-performing f/8 AF sensors, and a new 100-400L that goes with it that's designed to be dead-sharp wide open with a 1.4x TC on it on that camera (which could AF with it that way), and to have all that other stuff fixed. The ideal one would be f/4.5 at 300mm and have AF faster than the 400/5.6L while weighing the same, thus eliminating the need for the 300/4L IS and the 400/5.6L.

That system would be virtually the ultimate hand-holdable "reach" camera system for good light applications.


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