# Patent - EF 50 f/1.4



## Canon Rumors Guy (May 25, 2011)

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<p><strong> </strong></p>
<p><strong></p>
<div id="attachment_6571" class="wp-caption alignnone" style="width: 310px"><img class="size-medium wp-image-6571" title="2011_70032_fig19-82479 (1)" src="http://www.canonrumors.com/wp-content/uploads/2011/05/2011_70032_fig19-82479-1-300x185.png" alt="" width="300" height="185" /><p class="wp-caption-text">EF 50 f/1.4</p></div>
<p></strong></p>
<p><strong>Canon patent for EF 50 f/1.4 USM

</strong></p>
<ul>
<li>Patent Publication No. 2011-70032</li>
<li>Published 2011.4.7</li>
<li>Filled 2009.9.25</li>
</ul>
<p><strong>Specifications</strong></p>
<ul>
<li>Focal Distance: 51.70</li>
<li>Fno: 1.30</li>
<li>Half angle of view: 22.79</li>
<li>Image Height: 21.64</li>
<li>Lens Length (mm): 98</li>
<li>Back Focus (mm): 37.5</li>
<li>Aspherical: 2</li>
</ul>
<p>The current 50 f/1.4 , while a bargain, isÃ‚Â definitelyÃ‚Â due for a replacement.</p>
<p><strong><span style="color: #ff0000;">c</span>r</strong></p>
<p><a href="http://www.bhphotovideo.com/c/product/12140-USA/Canon_2515A003_50mm_f_1_4_USM_Autofocus.html?BI=2466&KBID=3296">Canon EF 50 f/1.4 $449 at B&H</a></p>
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## 7enderbender (May 25, 2011)

Any experts who are able to explain what the potential differences may be? To me this looks like the same design Canon had for the last 40 years - which I think is great by the way.

What is the thing marked as "Ggi 1"? And could it be that the lens element in the back is bigger?

So, anyway - what ever they'll do I hope it'll be better mechanically.


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## Justin (May 25, 2011)

7enderbender said:


> Any experts who are able to explain what the potential differences may be? To me this looks like the same design Canon had for the last 40 years - which I think is great by the way.
> 
> What is the thing marked as "Ggi 1"? And could it be that the lens element in the back is bigger?
> 
> So, anyway - what ever they'll do I hope it'll be better mechanically.



usm?


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## Darkwand (May 25, 2011)

The 50mm f/1.4 is in stock at like 1 store in Sweden at the moment.

A theory is that the production line got hit by the tsunami and a factory that produces components for the older lenses got hit. Therefore instead or rebuilding an out of date production line Canon redesigns their older lenses to use newer parts. This would with the patent for the 24mm f/2.8 as well.


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## anthony11 (May 25, 2011)

I wonder, though, if the EF non-L primes sell enough these days for Canon to feel that a redesign and everything associated with a new product is warranted. In recent years there seems to have been a pattern of letting non-L primes wither.


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## DJL329 (May 26, 2011)

anthony11 said:


> I wonder, though, if the EF non-L primes sell enough these days for Canon to feel that a redesign and everything associated with a new product is warranted. In recent years there seems to have been a pattern of letting non-L primes wither.



Perhaps now that they updated a lot (most?) of the L primes, they're finally getting around to the non-L primes. The 15mm Fisheye would be one example.


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## DJL329 (May 26, 2011)

Justin said:


> 7enderbender said:
> 
> 
> > Any experts who are able to explain what the potential differences may be? To me this looks like the same design Canon had for the last 40 years - which I think is great by the way.
> ...



Definitely has to have USM. A reduced MFD would also be nice, as some of the newer primes have.


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## J-Man (May 26, 2011)

Optically it could be the same other than possibly the new sub wavelength coating, and USM ring AF motor.

Personally I'd like to see it get the L treatment.


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## Aputure (May 26, 2011)

This is long overdue. I'm looking to get this or the 1.2, while holding out with my 1.8 for the time being. Nothing wrong with the nifty fifty for the price!


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## gmrza (May 26, 2011)

anthony11 said:


> I wonder, though, if the EF non-L primes sell enough these days for Canon to feel that a redesign and everything associated with a new product is warranted. In recent years there seems to have been a pattern of letting non-L primes wither.



I wonder if it is a case of letting non-L primes wither, or whether other lenses (especially a lot of zooms) have been in much greater need of an update...


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## Jamesy (May 26, 2011)

I wonder how this will stack up against the Sigma 50/1.4, which I hear is of superior design to the current Canon 50/1.4. The Sigma has a 77mm filter and is a BIG chunk of glass - I wonder if the new Canon 50/1.4 will be as big.


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## Admin US West (May 26, 2011)

Jamesy said:


> I wonder how this will stack up against the Sigma 50/1.4, which I hear is of superior design to the current Canon 50/1.4. The Sigma has a 77mm filter and is a BIG chunk of glass - I wonder if the new Canon 50/1.4 will be as big.



It should have no trouble beating the Sigma, since the existing 50mm f/1.4 beats the Sigma on FF cameras, but is better on crop cameras.

http://www.photozone.de/canon-eos/522-sigma50f14eosff

Verdict
The new Sigma AF 50mm f/1.4 EX DG HSM showed pretty impressive results in our APS-C review. However, it's not quite as convincing on full format cameras. The center quality of the lens is certainly fine and even great from f/2 onwards. Unfortunately the border & corner performance is rather disappointing. It's downright soft at large apertures and never really better than good even at the very best setting (f/8). The amount of vignetting is quite heavy at f/1.4 but that's rather typical for such lenses. If you stop down to f/2.8 this will not be a real issue anymore though. The lens produces moderate barrel distortions which is a tad more than the standard in this lens class. Lateral CAs are very well controlled and not really field relevant. The bokeh is quite decent although not perfect either. 
A real highlight of the lens is certainly its build quality. Unlike most 50mm f/1.4 it features a metal body and a good focus ring. The HSM AF drive is very fast and virtually silent. Unfortunately the lens suffers from residual spherical aberrations (focus shifts) when stopping down so accurate focusing can be tricky.


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## Jamesy (May 26, 2011)

I have heard good things about the Sigma but I have not tried it. I own the nifty fifty and owned the Canon 50/1.4 for a brief period but sold it becasue of the softness and purple fringing on anything less than F2ish. When I read up on it (1.4) it turnns out this is pretty normal - I didn't find the cost justification to keep the 1.4 so I flipped it.

I look forward to the new 50/1.4, perhaps the shortcomings of the current lens will be addressed.


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## LetTheRightLensIn (May 26, 2011)

7enderbender said:


> Any experts who are able to explain what the potential differences may be? To me this looks like the same design Canon had for the last 40 years - which I think is great by the way.
> 
> What is the thing marked as "Ggi 1"? And could it be that the lens element in the back is bigger?
> 
> So, anyway - what ever they'll do I hope it'll be better mechanically.



Simply adding true ring USM would help. The current version breaks non-stop and doesn't focuses well. It's a joke of an AF design that is basically a design flaw. The clutched micro-USM, unique in all the world to this lens, must go.

Maybe Ggi 1 is that new lens coating? Maybe it would make wide open a little less washed out from internal reflections??


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## LetTheRightLensIn (May 26, 2011)

Darkwand said:


> The 50mm f/1.4 is in stock at like 1 store in Sweden at the moment.
> 
> A theory is that the production line got hit by the tsunami and a factory that produces components for the older lenses got hit. Therefore instead or rebuilding an out of date production line Canon redesigns their older lenses to use newer parts. This would with the patent for the 24mm f/2.8 as well.



If the design for this is barely changed, then perhaps.
But if the ones for the 24 2.8 and such are different, well, it often takes a few years to work out a good design so it seems to quick to be related to the quake I'd think. But maybe they had the plans and had decided ot never use them and just be cheap and stuck with old design but then plant got wiped out so they go to these??


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## neuroanatomist (May 26, 2011)

7enderbender said:


> What is the thing marked as "Ggi 1"?... So, anyway - what ever they'll do I hope it'll be better mechanically.



An optical element Ggi1 includes a medium that has a refractive index distribution. This optical element satisfies conditions of:

|θF(pmax)−θgF(pmin)|≧0.02, |ΔθgFgi(p1)|≧0.0272, Δθgdgi(p1)|≧0.0250, and |θgFgi(pmaxgi)−θgFgi(pmingi)|≦0.1.

Even if it's not mechanically better, it'll be _mathematically_ better. 

(Translation: Ggi1 is what the marketing department calls subwavelength structure coating.)


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## 7enderbender (May 26, 2011)

neuroanatomist said:


> 7enderbender said:
> 
> 
> > What is the thing marked as "Ggi 1"?... So, anyway - what ever they'll do I hope it'll be better mechanically.
> ...



Ah! Makes sense. So in other words: we may be looking at the same 50 1.4 we enjoyed since the 70s with different coating - and hopefully better mechanical qualities.

I would love that and be willing to trade in mine for a premium.


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## IronMike (May 26, 2011)

It looks like a different optical design, this patent has 8 elements in 6 groups, and the original has only 7 in six groups. It is the elements behind the stop that have changed.

http://www.canon.com/camera-museum/camera/lens/ef/data/standard/ef_50_14_usm.html?p=2

The performance wide open of the current lens is not that great, it suffers from spherical aberation causing halation. The good news is that this patented lens has 2 aspherical elements which might (speculatively) improve the image at 1.4.

While the focusing on my 50mm f1.4 has never bothered me that much (and is still working fine, fingers-crossed)
it is not super accurate and an upgrade to true ring-USM would be welcome. Hopefully if it does come out it won't be too expensive...

Mike


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## dgsphto (May 26, 2011)

Yes, the optical design seems to have been changed from the current 50/1.4.

Hopefully they will introduce it soon.


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## Admin US West (May 27, 2011)

It appears to feature a coating with a radial gradient refractive index (The gg1 and gg2). Canon seems to be releasing a whole host of patents for lenses using the process, so they may have perfected a process to manufacture lenses to the required and repeatable tolerances, or might be just protecting their invention until it becomes practical to manufacture.

This is basically what the gg coatings do:

An optical system includes a positive lens unit, wherein the positive lens unit includes an optical element containing a base material and minute particles that are mixed with the base material and have Abbe number that is lower than that of the base material, and the minute particles are higher in density at a peripheral portion of the optical element than on an optical axis of the optical element.


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