Patent: Soft Focus Lens Designs, Various Focal Lengths

Canon Rumors Guy

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Canon has filed a patent <a href="https://www.canonnews.com/canon-patent-application-soft-focus-lenses">spotted by Canon News</a> for a variety of soft focus lenses. The most interesting of the bunch is a 70-200 f/4 full frame lens with a backfocus of 25mm, meaning it’s not an EF mount lens.</p>
<p><strong>35mm f/1.8 full frame EF Canon mount</strong></p>
<ul>
<li>Focal Length 33.75</li>
<li>F-Number 1.72</li>
<li>Image Height 21.64</li>
<li>Total Lens Length 132.93</li>
<li>BF 39.14</li>
</ul>
<p><strong>58mm f/1.4 full frame EF Canon mount</strong></p>
<ul>
<li>Focal Length 57.57</li>
<li>F-Number 1.43</li>
<li>Image Height 21.64</li>
<li>Total Lens Length 160.04</li>
<li>BF 40.43</li>
</ul>
<p><strong>105mm f/2.0 full frame EF Canon mount</strong></p>
<ul>
<li>Focal 103.2</li>
<li>F-Number 2.17</li>
<li>Image Height 21.64</li>
<li>Total Lens Length 123.79</li>
<li>BF 42.2</li>
</ul>
<p><strong>70-200 f/4 full frame BF of 25mm (not EF mount)</strong></p>
<ul>
<li>Focal 72.21 – 194.06</li>
<li>F-Number 4.00</li>
<li>Image Height: 21.64</li>
<li>BF 25.98</li>
</ul>
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ahsanford

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jolyonralph said:
Again, most patents don't end up as products.

But I'm curious, who on earth wants a soft focus lens these days?

Unless this means an apodization filter, which I think it could be (the part labelled SP in the diagrams)

Canon was tired of leaving all the LensBaby money on the table. ;D

- A
 
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ahsanford said:
jolyonralph said:
Again, most patents don't end up as products.

But I'm curious, who on earth wants a soft focus lens these days?

Unless this means an apodization filter, which I think it could be (the part labelled SP in the diagrams)

Canon was tired of leaving all the LensBaby money on the table. ;D

- A

Nailed it! I'm surprised they aren't producing present versions with insane amounts of flare and aberrations. Some crazy filters are popular with the younger generation.
Bad in the day, we used to smear Vaseline on a filter for soft effects. :p
 
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KeithBreazeal said:
ahsanford said:
jolyonralph said:
Again, most patents don't end up as products.

But I'm curious, who on earth wants a soft focus lens these days?

Unless this means an apodization filter, which I think it could be (the part labelled SP in the diagrams)

Canon was tired of leaving all the LensBaby money on the table. ;D

- A

Nailed it! I'm surprised they aren't producing present versions with insane amounts of flare and aberrations. Some crazy filters are popular with the younger generation.
Bad in the day, we used to smear Vaseline on a filter for soft effects. :p

I use Lee Filters soft effects filters for portraits sometimes, they don't destroy sharp features like eyes but they do make highlights "glow" and help smooth out skin.

In the movie industry weve seen a huge increase in the use of low contrast or soft fx filters over the last two years because those vast amount of MPs don't make actresses in particular look good.
 
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ahsanford

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jeffa4444 said:
I use Lee Filters soft effects filters for portraits sometimes, they don't destroy sharp features like eyes but they do make highlights "glow" and help smooth out skin.

In the movie industry weve seen a huge increase in the use of low contrast or soft fx filters over the last two years because those vast amount of MPs don't make actresses in particular look good.

Can't you somewhat get that same effect with a Clarity negative slider move?

- A
 
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Apr 23, 2018
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not much explanation to the "soft focus" thing? is it
1. an "apodization filter" as implemented in eg the 56/1.2 Fuji lens? https://dpreview.com/articles/4106200256/fujifilm-introduces-xf-56mm-f1-2-r-apd-with-apodization-filter or
2. a new/"updated" appearance of the old "SF" Canon used in their (1987, now discontinued?) EF 135/2.8 SF lens? https://www.the-digital-picture.com/Reviews/Canon-EF-135mm-f-2.8-with-Softfocus-Lens-Review.aspx or
3. something entirely different?

maybe someone has looked at the patent detail? i dont really want to, just mildly curious. :)

not convinced at all that this patent will result in actual products.

re BF: 26mm backfocus would be about in line with my expections for "wisely chosen" Canon "EF-X" new native "slim" mirrorless FF mount parameters. BF in patents typically is a bit shorter than FFD. EF-M FFD is 18 mm. so 25mm BF lens does not "appear" to be designed for EF-M mount.
see patent for an EF-M 9-18mm BF is 14-16mm (wide end, long end).
http://www.canonrumors.com/patent-canon-ef-m-9-18mm-f3-5-4-5/

only my conclusion (guess, conjecture, ASSumption) though. :)


but again, what gives me more pause re. this patent is the "soft focus" bit. cannot see sufficient market for it, when any of these IQ-degrading effects can easily be added via software - in camera or in post-process.
 
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jolyonralph

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fullstop said:
BF in patents typically is a bit shorter than FFD. EF-M FFD is 18 mm. so 25mm BF lens does not "appear" to be designed for EF-M mount.
see patent for an EF-M 9-18mm BF is 14-16mm (wide end, long end).

Don't forget the FFD only defines the *minimum* BF (and even then it can sometimes extend into the body), there's nothing stopping a lens designer using the EF-M mount and having the same BF as a standard EF lens, should they be lazy enough to do things that way.

In wide angle lenses the BF is usually pretty close to the FFD, but on longer lenses there's usually a big difference. The 70-200 lenses for EF mount for example needs a gap for the extender.

So - long story short, you can't draw *any* conclusions about the FFD of the new mount from this lens.

In fact, all evidence so far is still pointing towards a FF capable EF-M mount - which I still think will be the best solution.
 
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I agree, the only "highly likely conclusion" is that this 70-200 patent is not for EF mount [44mm FFD]. NF for the other 3 lenses in the patent is also quite a bit shorter than 44mm, but by far not as much as on that 70-200.

jolyonralph said:
In fact, all evidence so far is still pointing towards a FF capable EF-M mount - which I still think will be the best solution.

no and no. :)
Canon execs responsible for EF-M themselves have clearly stated in an interview [I linked to it in some other thread] that it is not intended for FF image circle. But if you have newer "evidence" that they changed their mind on this, please provide information.
 
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jolyonralph

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fullstop said:
Canon execs responsible for EF-M themselves have clearly stated in an interview [I linked to it in some other thread] that it is not intended for FF image circle.

Well, I don't know what they said, but I really don't think there's any coincidence that the mount is almost identical to the sony E/FE mount and also the same throat width as Nikon F mount, both of which obviously work for a FF image circle.

EF-M is perfectly capable of FF. Look at the Sony FE mount as an example. When you mount an adaptor such as the Metabones on the mount and plug in a standard EF lens there's no additional vignetting - the mount is perfectly designed for a FF image circle.

Now, that doesn't mean they WILL use EF-M for mirrorless, as there are clearly many reasons to keep the EF mount. But I doubt that Canon would create yet another incompatible mount format. Keeping to the EF-M mount means that future FF mirrorless lenses would also work on their APS-C cameras - as the EF lenses do on EF-S mount cameras, why would Canon go backwards and create incompatible mounts between their APS-C and FF mirrorless options when there is absolutely no need to?
 
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jolyonralph said:
fullstop said:
Canon execs responsible for EF-M themselves have clearly stated in an interview [I linked to it in some other thread] that it is not intended for FF image circle.

Well, I don't know what they said, but I really don't think there's any coincidence that the mount is almost identical to the sony E/FE mount and also the same throat width as Nikon F mount, both of which obviously work for a FF image circle.

EF-M is perfectly capable of FF. Look at the Sony FE mount as an example. When you mount an adaptor such as the Metabones on the mount and plug in a standard EF lens there's no additional vignetting - the mount is perfectly designed for a FF image circle.

Now, that doesn't mean they WILL use EF-M for mirrorless, as there are clearly many reasons to keep the EF mount. But I doubt that Canon would create yet another incompatible mount format. Keeping to the EF-M mount means that future FF mirrorless lenses would also work on their APS-C cameras - as the EF lenses do on EF-S mount cameras, why would Canon go backwards and create incompatible mounts between their APS-C and FF mirrorless options when there is absolutely no need to?


no. EF-M is NOT "perfectly capable of FF". Just like the poorly chosen Sony E-mount it would entail MASSIVE compromises to press it into FF service. In the form of lenses that rre not as compact as they could and should be, more complex than they could and should be and wy more expensive than they could and should be. See Sony FE ... no lens I would buy over there. Either subpar performance and high price or performance on par with Canon glass and 30-50% more expensive. A lot of it is due to Sony's decision to use E-mount with its "well chosen for APS-C" parameters also for FF image circle. Ever wondered why there is so much hollow air-filled tube at the mount end of those stupid Sony FE lenses?

Why is it, that you guys always find time to post but are NEVER able to google something and read it first? SO here is AGAIN the link to the interview with the Canon guys who actually DESIGNED the EF-M mount:
https://translate.google.com/translate?depth=1&hl=en&ie=UTF8&prev=_t&rurl=translate.google.com&sl=auto&sp=nmt4&tl=en&u=https://dc.watch.impress.co.jp/docs/news/551672.html

And to make it even easier for all "reading-challenged posters", here the important piece:

- Where is the most important factor in developing a new mount called "EF - M"?
Nakamura: It is a mount diameter that satisfies the APS - C size image circle properly, but also to make it possible to realize small size and light weight. In addition, the operation feeling such as attaching and detaching the lens is designed to be the same as the EF mount.
EF-M mount. The mount diameter is also reduced from the EF mount

- Can the EF-M mount correspond to sensors larger than APS - C size, eg 35 mm full size sensor?
Kikuchi: I think that I can not do that. I can not say that if I do something strange, I will not physically enter ... .... It is a level that the amount of marginal light falls considerably or that you do not know what the image will be like.

in other words: "not designed for FF, maybe borderline possible, but only with MASSIVE COMPROMISES". See Sony FE. Any questions?

TL;DR: Canon EF-M is not a suitable, good mount for FF image circle. Canon knows that. Most likely it is one of the main reasons they have not been able to launch a FF mirrorless system yet.
 
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Jul 21, 2010
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fullstop said:
in other words: "not designed for FF, maybe borderline possible, but only with MASSIVE COMPROMISES". See Sony FE. Any questions?

And yet...Sony E-mount full frame lenses from Sony (GM) and Zeiss deliver excellent IQ. Sure, they’re no smaller than equivalent EF lenses. But the compromise is only ‘MASSIVE’ because you personally want a FF MILC system that’s as small as possible, or even smaller. Get this fact through your thick skull – YOU DO NOT REPRESENT THE MARKET.
 
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you might want to be a bit more careful with your ASSumptions. :)

I am definitely "representative" for a much larger portion of the stills imaging market than you.

How many (private) Canon EF 600/4 owners are there globally? 10.000 ? More? Less?

And how many potential buyers of a compact, fully competent, enthusiast-affordable mirrorless Canon FF camera system are out there?

... owned. ;D
 
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