# Patent: Canon EF 58mm f/1.4



## Antono Refa (Oct 2, 2015)

http://egami.blog.so-net.ne.jp/2015-10-02


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## Haydn1971 (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*

I'm hopeful that this is the parallel super lens "fifty" L that I'm expecting to compliment the more artful 1.2 "fifty"

Which could end up with....

50mm f1.2 L artful mistress left to age gracefully
58mm f1.4 L new kid bad boy sharply contrasty mega lens to beat Otus
50mm f1.8/2.0 IS running with the 35mm IS theme, the sensible type
50mm f1.8 STM nifty fifty for the experimental types

I'm kinda expecting the 58mm now to cost more than the 50mm f1.2 - which sounds odd, but with the focal length differentiator, Canon can PR themselves around a £2000 f1.4 lens


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## midluk (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*

Are there good reasons to choose 58mm over 50mm? You always read that 50mm has such a "natural" viewing angle on FF. So why go slightly but not significantly higher? Or is the "natural viewing angle" more like 58mm but to have a round number always 50mm has been used in the past? Would you even notice for daily work?


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## Antono Refa (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



midluk said:


> Are there good reasons to choose 58mm over 50mm? You always read that 50mm has such a "natural" viewing angle on FF. So why go slightly but not significantly higher? Or is the "natural viewing angle" more like 58mm but to have a round number always 50mm has been used in the past? Would you even notice for daily work?



Take the "50mm is natural viewing angle" with a grain of salt.

For starters, the numbers vary anywhere from the sensor's diagonal (= 43.266mm for FF) to 55mm (again, for FF). Then, lenses might have focus breathing, which means the focal length would change based on the focusing distance, and manufacturing inaccuracies. Finally, because it isn't accurate science, manufacturers round focal lengths (and max apertures) a bit, so a 50mm lens might have been designed to be a wee longer or shorter.

[IIRC, it was explained the focal length is accurate only if the lens is focused to infinity. There are others on the forum who can explain this a lot better than me.]

Which answers your last question - people usually don't notice in daily work.

My guess Nikon and Canon have found they can make a better lens (in terms of not only IQ, but weight, price, profit, etc as well) if they make it a few millimeters longer, so they did.


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## rs (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*

Translated link:
http://translate.google.com/translate?sl=auto&tl=en&u=http://egami.blog.so-net.ne.jp/2015-10-02







Patent Publication No. 2015-172611
Published 2015.10.1
Filing date 2014.3.11

Focal length 57.99
F-number 1.45
Half angle (in degrees) 20.46
Image height 21.64
Overall length of the lens 117.64
BF 38.23


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## Ruined (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*

This looks like the barrel will be quite a bit longer than the 50mm f/1.2l, probably comparable to the 35L II.


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## Canon Rumors Guy (Oct 3, 2015)

```
<p>A new patent for an EF 58mm f1.4 optical formula has appeared. Nikon currently has a Nikkor 58mm f/1.4G. Could we be getting closer to a replacement for the EF 50mm f/1.4?</p>
<p>Patent Publication No. 2015-172611 (Google Translated)</p>
<ul>
<li>Published 2015.10.1</li>
<li>Filing date 2014.3.11</li>
<li>Focal length 57.99</li>
<li>F-number 1.45</li>
<li>Half angle (in degrees) 20.46</li>
<li>Image height 21.64</li>
<li>Overall length of the lens 117.64</li>
<li>BF 38.23</li>
</ul>
```


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## bertrandG (Oct 3, 2015)

58mm f1.4 has the same depth of field as a 50mm f1.2
That might be the reasoning.


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## ajfotofilmagem (Oct 3, 2015)

It is very easy to beat the mediocre (and overpriced) Nikon 58mm, but is difficult to overcome the Sigma 50mm Art. :

Nikon 58mm F1.4





Sigma 50mm F1.4 Art


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## privatebydesign (Oct 3, 2015)

bertrandG said:


> 58mm f1.4 has the same depth of field as a 50mm f1.2
> That might be the reasoning.



Not for the same subject magnification it doesn't, and surely that is how most people frame their images?


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## JonAustin (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



Haydn1971 said:


> I'm hopeful that this is the parallel super lens "fifty" L that I'm expecting to compliment the more artful 1.2 "fifty"
> 
> Which could end up with....
> 
> ...



_* This is the lens I'm waiting for, although I'd like it to be faster, and I wouldn't mind if it turns out as a 58mm._ (Getting by fine with my 12-year-old 50/2.5 CM in the meantime.)


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## zim (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



Haydn1971 said:


> I'm hopeful that this is the parallel super lens "fifty" L that I'm expecting to compliment the more artful 1.2 "fifty"
> 
> Which could end up with....
> 
> ...



This is what I've been concerned about in previous posts. I really really hope this doesn't happen!


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## vscd (Oct 3, 2015)

>Overall length of the lens 117.64

Too long for a good Allrounder.


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## moreorless (Oct 3, 2015)

My guess would be that its a potential lens along the same lines as the Nikon 58mm, that lens might be hated by net gearheads but it seems to have become quite popular with portrait shooters, an area Canon has previously been quiet dominant with the 50mm and 85mm F/1.2's.

Perhaps it would make sense for Canon to release a 58mm to cater to that market with smoother bokeh/rendering and then release a 50mm F/1.2 or F/1.4 that goes after Sigma for extreme sharpness?


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## Mt Spokane Photography (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



midluk said:


> Are there good reasons to choose 58mm over 50mm? You always read that 50mm has such a "natural" viewing angle on FF. So why go slightly but not significantly higher? Or is the "natural viewing angle" more like 58mm but to have a round number always 50mm has been used in the past? Would you even notice for daily work?



Nikon has a long history of making 58mm lenses. Their famous 58mm f/1.2 Noct AI and AIS for example. 

http://www.ebay.com/itm/Nikon-Noct-Nikkor-58mm-f-1-2-AIS-Noctilux-Manual-Focus-A15I0046-/181890773369?hash=item2a5988f179

I can't say why 58mm, but the extra few mm probably makes it easier to increase sharpness and other characteristics of such a wide aperture.


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## Antono Refa (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



zim said:


> Haydn1971 said:
> 
> 
> > I'm hopeful that this is the parallel super lens "fifty" L that I'm expecting to compliment the more artful 1.2 "fifty"
> ...



What would you like to see improved in the 50mm f/1.2 that serves it's purpose, rather than to make it more like the new uber fifties lenses?


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## AvTvM (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



rs said:


> Translated link:
> http://translate.google.com/translate?sl=auto&tl=en&u=http://egami.blog.so-net.ne.jp/2015-10-02



Interesting. Pronounced concave meniscus front element. Rarely seen. new Zeiss Milvus 50/1.4 has a bi-concave front element.

http://www.zeiss.at/camera-lenses/de_at/camera_lenses/milvus/milvus1450.html

Is the Canon patent also a floating element design?


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## privatebydesign (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



Mt Spokane Photography said:


> midluk said:
> 
> 
> > Are there good reasons to choose 58mm over 50mm? You always read that 50mm has such a "natural" viewing angle on FF. So why go slightly but not significantly higher? Or is the "natural viewing angle" more like 58mm but to have a round number always 50mm has been used in the past? Would you even notice for daily work?
> ...



Canon have an equally long history with the 58mm lens, starting with the R58 f1.2 back in 1962. They carried that through to the FL mount in the 1964 FL58 f1.2 and a MkII version of the same lens in 1966.

In 1968 they changed to a 55mm focal length for their premier '50' and retained the f1.2, which continued into the next generation FD mount in 1971 with the FD55 f1.2 and FD55 f1.2 AL, the later earning the title as the _"worlds first interchangeable lens for 35mm SLR employing an aspherical lens element"_.

In 1973 we got two more 55mm f1.2 lenses, one aspheric and the other not, both with the new for the time S.S.C coatings. The aspheric version got another update in 1975. Indeed it wasn't until the two versions of the New FD 50 f1.2, one an L the other not, that the 55mm focal length was dropped.

I was a heavy user of the FDn 50 f1.2L and looked forwards to the release of the EF version, but I was bitterly disappointed with the EF's performance and although I have used several I never bought one, much preferring the performance of my long lasting EF 50 f1.4. 

P.S. I believe the FD55 f1.2 AL was the first, defacto, 'L' lens. The first actual L lens wasn't until the 1978 FD300mm f4L.


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## ahsanford (Oct 3, 2015)

Lovely IP, nice work Canon.

But that's years off. Where's the lens half this forum will pay you for _sight unseen_ upon its announcement?

We want to pay you money for this. It's an easy sale. Do it. Gimme gimme gimme.

- A


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## mb66energy (Oct 3, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



AvTvM said:


> rs said:
> 
> 
> > Translated link:
> ...



blue: The EF-M has it too: http://cweb.canon.jp/ef/lineup/ef-m/ef-m22-f2stm/spec.html 
and is a fine lens.

red: L1, L2 and L3 are three lens _groups _which gives the hint that it has floating elements - a standard with modern high aperture wide and standard lenses ...


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## aceflibble (Oct 3, 2015)

It'd be a helluva waist-up portrait lens for people with APS-C sensor bodies, and it'd be a slightly more useful full-length portrait lens for people on 35mm sensor bodies. Effectively the look of the 50mm f/1.2L but with a very, very slightly flatter perspective.


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## privatebydesign (Oct 3, 2015)

mb66energy said:


> AvTvM said:
> 
> 
> > rs said:
> ...




The Canon 35mm f2 from 1971 to 1976 also had a concave front element, along with some very exotic (and radioactive) ingredients that resulted in very good performance for the time. The lenses often show a yellow or amber colour cast nowadays.


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## TAF (Oct 3, 2015)

privatebydesign said:


> The Canon 35mm f2 from 1971 to 1976 also had a concave front element, along with some very exotic (and radioactive) ingredients that resulted in very good performance for the time. The lenses often show a yellow or amber colour cast nowadays.



Perhaps Canon will revisit this technology.

After all, without any film to fog, they could really get away with some seriously high levels here, and having a lens that really excels when new and then has an expiration date after which it is ruined has to be the dream of every manufacturer!


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## keithcooper (Oct 3, 2015)

*It's not about the focal length*

The exact focal length is not really the main point of this patent IMHO. 

Compare optical formulae with the Canon patent (50mm) from July.
That one also mentioned internal focus.

The Egami patent link now has 2 additional designs of 50mm and 58mm added

All compared:
http://www.northlight-images.co.uk/Canon_new_lenses.html

Quite a few variations there...


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## Meerkat (Oct 3, 2015)

I started with a Minolta 58mm 1.4. I loved it. I find that when I use my 24-105, many of my shots are around 60mm. I would buy a 58 if Canon releases one.


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## rowlandw (Oct 4, 2015)

For now I'll use my 35mm f/1.4 on crop.


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## zim (Oct 4, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



Antono Refa said:


> zim said:
> 
> 
> > Haydn1971 said:
> ...



The implication is that it goes EOL without replacement


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## davidmurray (Oct 4, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



Mt Spokane Photography said:


> midluk said:
> 
> 
> > Are there good reasons to choose 58mm over 50mm? You always read that 50mm has such a "natural" viewing angle on FF. So why go slightly but not significantly higher? Or is the "natural viewing angle" more like 58mm but to have a round number always 50mm has been used in the past? Would you even notice for daily work?
> ...



If you had a good optical formula that worked equally well at 50mm focal length and 58mm, and if you sell products using 50mm focal length and your direct competition sells products using 58mm, how would you prevent your competition from using the same basic formula in their product? Patent it! You don't need to use it yourself at 58mm when you're using it at 50mm and you can stop your competitor from using it at 58.


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## Antono Refa (Oct 4, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



zim said:


> Antono Refa said:
> 
> 
> > zim said:
> ...



I think the lack of an upgrade might be an indication it's a niche lens with less competition, and therefore less incentive to upgrade, relative to other lenses.

E.g. how long has it been since the 85mm f/1.2 mkII & MP-E 65mm were upgraded? The TS-E 24mm was upgraded in 2009, and AFAIK Nikon hasn't followed suit yet - apparently Nikon think it would get better ROI on other upgrades.

In other words, the lens might be sufficiently niche for the lack of upgrade not to indicate EOL.


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## Berowne (Oct 4, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



mb66energy said:



> AvTvM said:
> 
> 
> > rs said:
> ...



The Leica-M 35/1.4 Asph has also a concave front element. Floating elements with AF will not work. 

http://de.leica-camera.com/Fotografie/Leica-M/M-Objektive/Summilux-M-1-1,4-35-mm-ASPH 

Andy


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## keithcooper (Oct 4, 2015)

*more canon patents*

From last July

Canon have no shortage of ~50 mm designs...


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## AvTvM (Oct 4, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



Berowne said:


> The Leica-M 35/1.4 Asph has also a concave front element. Floating elements with AF will not work.
> Andy


Yes, there is a smallish number of (old) WIDE-ANGLE lenses with retrofocus design and concave front element. But not for lenses with focal lengths of 50 or 58mm. 
Zeiss has moved grom Planar design to Distagon with the new Milvus 50mm/1.4. And now this Canon patent ... Will be interesting to see whether it ever hors into production and if so, what performance it really will have.

AF is possible with floating element design. Canon EF 50/1.2 and 85/1.2 are living proof ... or the new Zeiss Batis 85/1.8 (which uses a conventional 1930s Sonnar design, with convex front element).


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## StudentOfLight (Oct 4, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



Berowne said:


> mb66energy said:
> 
> 
> > AvTvM said:
> ...


The New Tamron 45mm also uses a concave front element:


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## Berowne (Oct 4, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



AvTvM said:


> Berowne said:
> 
> 
> > The Leica-M 35/1.4 Asph has also a concave front element. Floating elements with AF will not work.
> ...



50L is a front focusing Design. Are you sure that is "floating elements"? FL means as i understand it, that both groups of lenses - the front group and a rear group - chance independendly and at once their position to the focal plane. This will need two AF-mechanisms in the lens. This means the position of the rear group is not fixed, as in a front focusing design.


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## zim (Oct 4, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



Antono Refa said:


> zim said:
> 
> 
> > Antono Refa said:
> ...



Well I'd like to hope that both 1.2 lenses are kept on an upgrade/refresh cycle no matter what Canon decides that cycle is and that they consider them 'professional' rather than 'niche' to warrant that cycle.

Nikon make lenses?? 


Regards


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## FTb-n (Oct 4, 2015)

As long as we are speculating, I expect the 50 1.2L USM to be replaced by a 50 1.2L USM Mark II. There are too many wedding photographers who love this lens to let it fade away. 

A 58 1.4 IS will either replace the 50 1.4, or never materialize. I'm still expecting Canon to compliment the 28 2.8 IS and the 35 2.0 IS with 50 IS (or 58 IS) and 85-100 IS lenses. The 50 1.4 is too popular to let it fade away. But, it seems a bit crowded to have a 50 1.8, 50 1.4, and a 50 1.2. Also, I'm not sure that there is a market to support both a 50 1.4 and a 58 1.4.

Personally, I'm waiting to see what Canon does to upgrade the 50 1.2L and the 50 1.4 before adding a 50 prime to my kit. My current needs don't justify a 50 1.2L, so I'm kind of hoping for a 50 1.4 IS to compliment my 35 2.0 IS. But, I'm actually more intrigued by a 58 1.4 IS as a compliment to the 35.


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## riker (Oct 4, 2015)

Nikon 58/1.4 is 1.5X times heavier and also 1.5X times longer than the current Canon 50/1.4. (Also 1cm bigger in diameter)

I really do NOT want that weight/size increase.
The power of current Canon 50/1.4 lies within being 1.4 AND small and light at the same time.
Otus and Sigma only have chance because Canon 50/1.2 is not good enough. Yet. As soon as it gets a serious upgrade the 1.2 will have a real advantage over the 1.4 lenses, especially from the marketing point of view.
(Not that you ever really need a 1.2 over a 1.4 at 50mm but anyway.)


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## AvTvM (Oct 4, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



Berowne said:


> 50L is a front focusing Design. Are you sure that is "floating elements"? FL means as i understand it, that both groups of lenses - the front group and a rear group - chance independendly and at once their position to the focal plane. This will need two AF-mechanisms in the lens. This means the position of the rear group is not fixed, as in a front focusing design.



Yes, I stand corrected, you are right: 50/1.2 L is no floating element design. EF 85/1.2L is. Seems to be the reason why the 50/1.2 L has that pronounced focus shift issue that should be corrected in any successor lens, no matter whether it is a Mk. II or something different (f/1.2 and/or 1.4, 50mm and/or 58 mm).

Autofocus is definitely possible also with floating element design. It may be more difficult to implement and it may well be the reason why the 85/1.2 L has focus-by-wire AF.


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## deleteme (Oct 4, 2015)

riker said:


> Nikon 58/1.4 is 1.5X times heavier and also 1.5X times longer than the current Canon 50/1.4. (Also 1cm bigger in diameter)
> 
> I really do NOT want that weight/size increase.
> The power of current Canon 50/1.4 lies within being 1.4 AND small and light at the same time.
> ...



I agree it will be larger but the lens manufacturers are listening to the demand for high performance and speed. The Otus line and Sigma Art line are quite popular and are making good money for the makers. 

Should the 50 1.2 get a makeover, it will not get smaller or cheaper. It will most likely strive to set the standard for excellence at that FL and aperture. When that happens a new legend will be born.


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## sdsr (Oct 5, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



midluk said:


> Are there good reasons to choose 58mm over 50mm? You always read that 50mm has such a "natural" viewing angle on FF. So why go slightly but not significantly higher? Or is the "natural viewing angle" more like 58mm but to have a round number always 50mm has been used in the past? Would you even notice for daily work?



55mm and 58mm used to be popular focal lengths in the pre-dslr era; I have a few which I enjoy using, including the Minolta 58mm 1.2 and Helios 44-2 (which is 58mm f2) and several 55mms. After using one for a day, 50mm can seem too short, while coming from 50mm it can, depending on what I'm doing, seem too long or usefully longer - all to an extent I wouldn't have expected. None of which really answers your question, of course. (If there are technical reasons for a manufacturer to prefer 58mm, that's out of my league completely....) On aps-c 58mm is closer than 50mm to what is usually regarded as the classic ff portrait length of 85mm (hence presumably the Fuji 56mm 1.2); maybe that is a factor too?


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## sdsr (Oct 5, 2015)

ajfotofilmagem said:


> It is very easy to beat the mediocre (and overpriced) Nikon 58mm, but is difficult to overcome the Sigma 50mm Art. :
> 
> Nikon 58mm F1.4
> 
> ...



It all depends on what you want; and if a lens tests badly that may say more about the test than the lens. Consider this, for instance:

https://photographylife.com/reviews/nikon-58mm-f1-4g

It's far more expensive than I would want to spend on such a lens, but that's partly because I have several elderly lenses that I like a lot, for which I paid vastly less, and which, I suspect, would test far worse!


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## Coldhands (Oct 5, 2015)

*Re: Canon patent for a 58mm f/1.4 seen in photorumors*



AvTvM said:


> Berowne said:
> 
> 
> > 50L is a front focusing Design. Are you sure that is "floating elements"? FL means as i understand it, that both groups of lenses - the front group and a rear group - chance independendly and at once their position to the focal plane. This will need two AF-mechanisms in the lens. This means the position of the rear group is not fixed, as in a front focusing design.
> ...



If you're curious, this article does a good job of showing the focus system for a lens with a floating element. Quite a simple mechanism, in fact. Floating elements are quite common in wide-angle lenses and almost universal in true macro lenses.

By the way, the focus shift in the 50mm f/1.2 is caused by under-corrected spherical aberration - floating elements wouldn't have any effect on this.


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## ajfotofilmagem (Oct 5, 2015)

sdsr said:


> ajfotofilmagem said:
> 
> 
> > It is very easy to beat the mediocre (and overpriced) Nikon 58mm, but is difficult to overcome the Sigma 50mm Art. :
> ...


Yes, it depends on the price.
If the Nikon 58mm F1.4 would cost up to $ 600 might be a good choice. But in US1700 is just mediocre when wide open. Chromatic aberration screams aloud: I am a 1970 project that has been repackaged and overpriced.

Hopefully Canon NOT do the same thing with his hypothetical 58mm F1.4.


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## ajfotofilmagem (Oct 5, 2015)

For those who did not understand my criticism:

Canon 50mm F1.4 from 1993, costing US$350





Nikon 58mm F1.4 from 2013, costing US$1700


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## Rudeofus (Oct 6, 2015)

At the moment there are two commonly employed ways to make a 50mm lens for slr cameras:

[list type=decimal]
[*]reverse telephoto design
[*]double gauss design
[/list]

The first design (used by Zeiss Otus and Sigma 50 Art) gives unwieldy lenses with exceptional sharpness. The second designis the more common one, it gives compact lenses with moderate sharpness (see Canon's current 50mm lineup). Main limitation of double gauss design is that you can't properly correct such a lens under its space constraints, there has to be sufficient space between rear element and film/sensor plane. A 58mm lens would give quite a bit more space, and therefore allow construction of a better lens which still uses the simple double gauss design.

As the patent implies, Canon still isn't there. 38mm back focus length is still too short for full frame slr cameras, so unless they make this a crop or mirrorless lens (which I think is extremely unlikely), this patent is not going to lead to a product anytime soon.


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## privatebydesign (Oct 6, 2015)

Rudeofus said:


> At the moment there are two commonly employed ways to make a 50mm lens for slr cameras:
> 
> [list type=decimal]
> [*]reverse telephoto design
> ...



Are you sure about that? With a flange distance of 44mm and a mount thickness of 5mm the current design gives 39mm of clearance, the electrical connections add another 2mm and the mirror doesn't swing past the connectors in the body. I don't see why back focus of 38mm isn't possible with the EF mount, the lens rear element would be extreme, but all these new lenses do seem to be pushing boundaries.


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## MayaTlab (Oct 6, 2015)

privatebydesign said:


> Rudeofus said:
> 
> 
> > At the moment there are two commonly employed ways to make a 50mm lens for slr cameras:
> ...



Agreed, otherwise nearly all of Canon's patents on Egami would be inappropriate for the EF mount, such as this one filed in 2011 for a rather double gaussish design : http://egami.blog.so-net.ne.jp/2013-06-11


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## Rudeofus (Oct 6, 2015)

privatebydesign said:


> Are you sure about that? With a flange distance of 44mm and a mount thickness of 5mm the current design gives 39mm of clearance, the electrical connections add another 2mm and the mirror doesn't swing past the connectors in the body. I don't see why back focus of 38mm isn't possible with the EF mount, the lens rear element would be extreme, but all these new lenses do seem to be pushing boundaries.


Given what you write 38mm should be doable, and the 85L seems to be one of these extreme designs where the rear element goes into the mount. I stand corrected.

What this still shows, is that double gauss design with better performance is only possible for fast glass with focal length > 50mm, although the Nikon 58mm still suggests that even 58mm isn't enough to create Otus like performance.


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## sdsr (Oct 6, 2015)

Rudeofus said:


> What this still shows, is that double gauss design with better performance is only possible for fast glass with focal length > 50mm, although the Nikon 58mm still suggests that even 58mm isn't enough to create Otus like performance.



You seem to assume that Nikon was trying to come up with Otus-like performance. If that assumption is true, they spectacularly failed, but the review I linked to earlier and the blurb on Nikon's website - which goes out of its way to mention the beautiful bokeh etc. (which isn't even mentioned in the blurb for most of their other 50-85mm lenses) of this lens - suggest that they weren't trying to. Either that, or they're attempting to make the most out of a failure.... 

Of course, even if the 58 1.4 performs as Nikon planned, I wonder how much better it is (if at all) than, say, the Minolta 58mm 1.4; you can buy one of those in excellent condition from KEH for $56.00 - i.e. c. 1/30 the price of the Nikon!


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## Rudeofus (Oct 6, 2015)

I am quite confident, that both Nikon and Canon could have created a reverse telephoto type 50mm lens, which would at least match the Sigma 50 Art in terms of sharpness. Both companies are not exactly newcomers, and both have created some incredibly sharp lenses before. 

At the same time, Canon's 50L and 85L, while not terribly sharp wide open, have a passionate following due to their beautiful bokeh. What Nikon (and now Canon) may have aimed for was a double gauss 58mm lens, which is a tad sharper than what they could have done with a 50mm lens, but still has decent bokeh.


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## Mika (Oct 6, 2015)

There are several things mentioned in this thread that I'd like to know where they originate from. You don't need to spare the technical details, I do optical design full time and can probably follow.

First is the notion that combination of a floating element and autofocus does not work. Where does this come from?

Second is: what do people mean with floating element? To me it means part of the objective moves at a different rate than the rest, and the rest may not move at all. This can be accomplished with a rather standard rail and cam system, and does not require several AF motors.

50/1.4 does not use a floating element, the entire objective barrel moves - I own this one and could check this is the case. 50/1.0L does have a floating element and focuses at least by extending the front, as does its sister objective 85/1.2. I don't have the 50/1.2L and can't say whether the entire assembly moves or whether just the front part moves.

EDIT:
The way I read the Canon 50 mm patent is that they are trying to think of a way of getting some retrofocus benefit without increasing the objective size or mass considerably while providing an improved image quality. They don't particularly need to do better than 50 mm Art or 55 mm Otus, just improve the EF50/1.4 and not increase the mass substantially.

And yes, 58 mm instead of 50 mm allows slightly more room for balancing the back focal distance with aberration correction. A back focal length of 38.5 mm should work fine with EF mount. One cannot go much closer, though. From the patents that I've seen, I think it is either 50/1.0 or 85/1.2 that has the shortest BFL of the EF objectives.


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## ahsanford (Oct 6, 2015)

Mika said:


> EDIT:
> The way I read the Canon 50 mm patent is that they are trying to think of a way of getting some retrofocus benefit without increasing the objective size or mass considerably while providing an improved image quality. They don't particularly need to do better than 50 mm Art or 55 mm Otus, just improve the EF50/1.4 and not increase the mass substantially.



*Yep.* The 50 f/nooneknows IS USM crowd -- specifically, the folks here who think this lens is not the future L but instead it's the future 50 f/1.4 USM replacement -- want to keep the size of this lens on or about where it is now. Save the big pickle jars for the next L.

Honestly, as much as we all want that lens to be a razor for sharpness, the 50 f/1.4 USM not wretched today. By far, the biggest improvements that lens needs has nothing to do with the optical formula. That lens needs an AF upgrade and a build quality upgrade far, far more than an optical upgrade. I know I'll wind people up and get this thread covered with everyone's soft f/1.4 shots taken on that 50 f/1.4, but people don't scream at that lens for its wide open softness -- they scream at the AF and the wimpy mechanical external focusing nonsense of that design.

For me -- and you may disagree -- just slapping proper modern fast reliable USM AF + internal focusing on the _exact same 50 f/1.4 optical design_ is worth a good $600-700 to me. That said, here's hoping we get a top to bottom new lens like the 24/28/35 IS refreshes. I'd buy that on day one.

- A


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## Rudeofus (Oct 8, 2015)

Mika said:


> And yes, 58 mm instead of 50 mm allows slightly more room for balancing the back focal distance with aberration correction. A back focal length of 38.5 mm should work fine with EF mount. One cannot go much closer, though. From the patents that I've seen, I think it is either 50/1.0 or 85/1.2 that has the shortest BFL of the EF objectives.


What's your prediction then? Nikon's 58mm faces harsh criticism for it's reported softness wide open, what are the odds that Canon will fare better in this regard? How would such a Canon 58mm F/1.4 fit into their lineup, given that their prosumer 50 is said to be acceptably sharp, whereas their 50L claims to be bokeh king?


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## Mika (Oct 14, 2015)

Rudeofus said:


> Mika said:
> 
> 
> > And yes, 58 mm instead of 50 mm allows slightly more room for balancing the back focal distance with aberration correction. A back focal length of 38.5 mm should work fine with EF mount. One cannot go much closer, though. From the patents that I've seen, I think it is either 50/1.0 or 85/1.2 that has the shortest BFL of the EF objectives.
> ...



Somehow I don't think Canon is going to launch 58 mm line-up. I think this patent is to hinder anybody else's possibility of providing 58 mm retrofocus objective.

What it comes to modernizing Canon's 50/1.4, the motor really has to improve. But I wouldn't pay more than 400 € for it. To be able to squeeze 600 € for that from me, it has to: [list type=decimal]
[*] Remain light and small enough (so I can use it abroad) 
[*] Have more reliable and accurate autofocus mechanism (everybody says Sigma drifts, but my EF50/1.4 is the only objective where I've noted it) 
[*] Keep it F/1.4 
[*] Provide a modest improvement in resolution.
[/list]

This is because I already have 50A and that serves me well enough for local photography, but it is too heavy for travel. Then again, Canon launched 50/1.8 STM, but I'd like to have the always on manual focus possibility. If they don't release 50/1.4 update soon, it's going to be the 50/1.8 STM then.


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