Patent: Canon 55mm f/1.4 & Other Primes

[Canon Rumors]

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<p>A few more patents for various “normal” fast prime optical formulas have appeared. Among them, another 35mm f/1.4 mention, as well as a 55 f/1.4. <a href="http://egami.blog.so-net.ne.jp/2014-07-07" target="_blank">Read the entire patent</a> to see the various optical formula images.</p>
<p><strong>Patent Description (Google Translated)</strong></p>
<ul>
<li>Patent Publication No. 2014-123018</li>
<li>Publication date 2014.7.3</li>
<li>Filing date 2012.12.21</li>
<li>Image height = 21.64mm</li>
<li>Inner focus</li>
</ul>
<table summary="embodiment" frame="box" rules="all">
<thead>
<tr>
<th>Example</th>
<th>Focal length</th>
<th>Fno.</th>
<th>Half angle</th>
<th>The overall length of the lens</th>
<th>BF</th>
<th>MOD</th>
</tr>
</thead>
<tbody>
<tr>
<td>One</td>
<td>49.53</td>
<td>1.45</td>
<td>23.60</td>
<td>99.46</td>
<td>38.10</td>
<td>450</td>
</tr>
<tr>
<td>Two</td>
<td>35.88</td>
<td>1.45</td>
<td>31.09</td>
<td>126.92</td>
<td>38.77</td>
<td>300</td>
</tr>
<tr>
<td>Three</td>
<td>55.42</td>
<td>1.45</td>
<td>21.33</td>
<td>100.44</td>
<td>40.24</td>
<td>450</td>
</tr>
<tr>
<td>Four</td>
<td>50.75</td>
<td>1.45</td>
<td>23.09</td>
<td>98.17</td>
<td>38.29</td>
<td>450</td>
</tr>
</tbody>
</table>
<p>Source: [<a href="http://egami.blog.so-net.ne.jp/2014-07-07" target="_blank">EG</a>]</p>
<p><strong><span style="color: #ff0000;">c</span>r</strong></p>

 

[chmteacher]

Re: Patent: Canon 55mm f/1.4 & Other Primes

May be better than sigma's Art line but at a higher price...

 

[Mt Spokane Photography]

Re: Patent: Canon 55mm f/1.4 & Other Primes

Its a inner focus lens, which should mean that it doesn't extend. That gives fast focusing speed, but lens abberations are a struggle to control. They claim that they are no worse when using their formula.

We need a 85mm f/1.2 patent with similar claims, very fast focus, and light weight.

Translation:
According to the present invention, quick focusing is easy at a wide field angle and a large diameter ratio, and the photographing optical system from which a long back focus is moreover obtained easily is acquired. They also claim light weight.
More snippets:

The movement magnitude of a focusing glass group can lessen this inner focus system to the focusing system to which the photographing optical system whole system is moved, and a miniaturization and weight saving of a focusing glass group are easy for it.
[0004]
As a result, since movement for focusing can be performed at high speed and the driving torque at the time of focusing can be reduced, when it applies to the photographing instrument which has an automatic-focusing detection device, for example, it becomes easy to miniaturize a drive motor.

So, no IS, but lighter, cheaper (to build), and faster.
This is beginning to sound like a consumer lens, not a expensive "L" type.

 

[Rudeofus]

Re: Patent: Canon 55mm f/1.4 & Other Primes

So, no IS, but lighter, cheaper (to build), and faster.
This is beginning to sound like a consumer lens, not a expensive "L" type.

I'd be not so sure about this. If Canon patents a 35mm and a 55mm design with very similarly looking construction, the 55mm design is most likely a retrofocal design. This would follow the recent trend started by Zeiss 55mm Otus and Sigma 50 Art and should be considered a good thing. Expect heavy, expensive and good to excellent imaging performance. And you are right, no IS.

It sounds like Canon will finally release a ~50mm lens worth looking at ...

 

[Viggo]

Re: Patent: Canon 55mm f/1.4 & Other Primes

So, no IS, but lighter, cheaper (to build), and faster.
This is beginning to sound like a consumer lens, not a expensive "L" type.

I'd be not so sure about this. If Canon patents a 35mm and a 55mm design with very similarly looking construction, the 55mm design is most likely a retrofocal design. This would follow the recent trend started by Zeiss 55mm Otus and Sigma 50 Art and should be considered a good thing. Expect heavy, expensive and good to excellent imaging performance. And you are right, no IS.

It sounds like Canon will finally release a ~50mm lens worth looking at ...

You took the words out of my mouth, completely agreed.

 

[dolina]

Re: Patent: Canon 55mm f/1.4 & Other Primes

Little money in Stills so I am guessing these will be Cinema lenses.

 

[AG]

Re: Patent: Canon 55mm f/1.4 & Other Primes

Little money in Stills so I am guessing these will be Cinema lenses.

Doubtful otherwise they would be in T stops not F stops.

Is there anything in the patent that says that these are EF lenses? Could they be EF-s or M mount?

 

[rs]

Re: Patent: Canon 55mm f/1.4 & Other Primes

Is there anything in the patent that says that these are EF lenses? Could they be EF-s or M mount?

The image height is 21.64mm - that's the radius of the image circle (or half the diameter). EF lenses are designed to cover a sensor with a 43mm diagonal, so these are FF lenses.

 

[GMCPhotographics]

Re: Patent: Canon 55mm f/1.4 & Other Primes

Dissapointingly, the three 50/51/55mm f1.4 designs all seem to be using gausian optics...which has largely been the blame for poorly resolving optics. Both the Carl Zeiss and Sigma 50mm lenses use a back focus design (simular to the 35mm f1.4) to resolve a higher resolution. Gausian optics offer a smaller and light weight construction, but at the expense of more optical defects and lower optical resolution.

I was hoping to see a new approach from Canon with their 50mm optical formulas, but these three patents look like the same old, same old. If any of these three lenses make it to the market place (and that's a big "IF") then i doubt we'll see much improvement over the old one...which makes me ask...why bother?

 

[l_d_allan]

Re: Patent: Canon 55mm f/1.4 & Other Primes

So, no IS

Would a patent mention whether there is IS or not? Seems that could be a separate issue.

I'd really like to see a 50mm to 55mm f1.4 with IS. I think IS would be a compelling advantage over the Sigma ART .... plus more modern optics. The OTUS without AF .... no interest, even if it wasn't so pricey.

FWIW: I am very happy with my EF 35mm f/2 IS, so a focal length of about 50mm doesn't interest me. An EF 85mm f2 IS might interest me enough to consider purchase, obviously depending on price.

 

[Rudeofus]

Re: Patent: Canon 55mm f/1.4 & Other Primes

Would a patent mention whether there is IS or not? Seems that could be a separate issue.

Even if Canon tried to sneak an IS lens by us, its image cycle would give away all the secrets. Since the image cycle of these lenses is barely large enough to cover a full frame sensor, we can be reasonably sure that these lens designs will not support IS.

 

[Marsu42]

Re: Patent: Canon 55mm f/1.4 & Other Primes

I was hoping to see a new approach from Canon with their 50mm optical formulas, but these three patents look like the same old, same old. If any of these three lenses make it to the market place (and that's a big "IF") then i doubt we'll see much improvement over the old one...which makes me ask...why bother?

Canon's more clever than you think - buy sticking with the outdated 50/1.4 and the ultra-outdated 50/1.8 *any* improvement will be a biggie, and people will buy them as long as there's a Canon label on them... a "real" usm would be worth the upgrade alone no matter the iq.

 

[GMCPhotographics]

Re: Patent: Canon 55mm f/1.4 & Other Primes

I was hoping to see a new approach from Canon with their 50mm optical formulas, but these three patents look like the same old, same old. If any of these three lenses make it to the market place (and that's a big "IF") then i doubt we'll see much improvement over the old one...which makes me ask...why bother?

Canon's more clever than you think - buy sticking with the outdated 50/1.4 and the ultra-outdated 50/1.8 *any* improvement will be a biggie, and people will buy them as long as there's a Canon label on them... a "real" usm would be worth the upgrade alone no matter the iq.

I've never really cared for the current 50mm f1.4 USM. Wide open, is got a low contrast and milkyness to the images I don't particularly like. Sure I can fix it in post Prod...but I really can't be bothered for the results. The build is really sub par, I've broken several and that's why I eventually upgraded to the L version. These days, I don't have need for a specific 50mm prime, so I cover the occasional requirement with a f2.8 zoom lens.
I have a mkI 50mm f1.8 (with the metal mount) which I got new with the original Canon AF camera (EOS 650). I still have the camera but I don't use film any longer, but the lens still works fine. Not bad results from it, nicer than I ever saw from the f1.4 version wide open.

I'm not sure Canon has done anything "deliberate" here. I think they have gone and re-designed these lenses formula based on an old model / requirement. Sigma and Zeiss have changed the approach to 50mm lens design and Canon haven yet to notice. We are probably about 5 years away from seeing any new 50mm prime from Canon which any dramatic change in optical formula. Lets face it, we'd all rather see a 100-400L replacement over a new 50mm!

 

[Mika]

Re: Patent: Canon 55mm f/1.4 & Other Primes

Interesting, these are actually not Double Gauss type designs, but I'd say they are retrofocus types. Though with 50 mm examples it's harder to see, I may take a look at these when I get back from vacation as I'm still not sure how much negative power does that 2nd lens provide. Groups G3a and G3b have concave sides facing each other, and this is a departure from classical Double Gauss. My gut feeling is that G3a and G3b will be relatively sensitive with respect to element decenters.

Canon has patented retrofocal designs before, but this seems like a more realizable one. I'd say their designers wanted to keep the objective small and light weight, while providing improved image quality and better focusing over the older 50/1.4. Whether these will be released as a product is another thing.