Patent: EF-M 70-400 f/4.5-7.2 STM
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Hi lw!lw said:People are adding 2 and 2 together and making 5.
This is a patent for the optical design of a lens. Not a spec for a product.
Hence it isn't that significant that it doesn't appear to have IS. It is just a patent.
Nor anywhere in the patent does it even mention an EF-M mount or the EOS M system - its just a patent, not a product...
Only the rumour sites are putting 2 and 2 together and deciding it might be an EF-M lens.
It may be true of course - but folks need to remember, its just a patent.
Sorry to correct your math a little bit. I am sure the people, that studied this patent did a right "2+2=4".
You are right, that this is JUST a patent and therefore it is not yet any product or ever will be.
But the conclusions from this patent that it would be EF-M, that it has no IS and so on are easy to make (compare to former patents and speculations on it):
1. IS: an IS is a relevant part of the optical formula and therefore appears in the patent text and drawing.
2. Information like image height, distance to image plan (IP in the drawing), back focus (BF) and so on clearly can define,
if a patent is for EF (FF), EF-S or EF-M (both APS-C, but different distance to IP).
So people who are familiar to optics can say: "This will be an EF-M".
And then it’s up to logic: Do you believe an EF-M tele zoom lens will be an "L" or will have "ring USM"?
And now you've found the reason for STM driven AF.
Maybe something is translated or calculated wrong (see here aperture of 7.0 to 7.2) but everything else is almost clear.
So the one question left will be: Will this become a product or not?
Here I'd say "No!" I don't believe it, due to the missing IS, which I cannot find in drawing or text.
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The source for the info states that is EF-M. Patents for lenses that have IS show that it is an IS lens (check rumours and patents for eg the recent 100-400L). This site is called Canon Rumors, hence a lot of speculation and guessing are to be expected.lw said:People are adding 2 and 2 together and making 5.
This is a patent for the optical design of a lens. Not a spec for a product.
Hence it isn't that significant that it doesn't appear to have IS. It is just a patent.
Nor anywhere in the patent does it even mention an EF-M mount or the EOS M system - its just a patent, not a product...
Only the rumour sites are putting 2 and 2 together and deciding it might be an EF-M lens.
It may be true of course - but folks need to remember, its just a patent.
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neuroanatomist said:jasny said:Maximilian said:
Apart from the possibility that IBIS body is coming…Surely IBIS makes more sense in mirrorless than in DSLR (image stabilisation in EVF).
Maybe it's a lens for the Sony E-mount...
Probably
Speaking of probability, IBIS from Canon is close to 0...
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neuroanatomist said:
But to be clear, the Patent says
The present invention is suitably used as an imaging optical system of imaging devices, such as a video camera, a digital still camera, a surveillance camera, a camera for films, and a camera for broadcast, concerning the imaging device which has a zoom lens and it.
It doesn't even say it is for an interchangeable lens camera, yet alone an EF-M mount...
It could be. But equally, it could not.
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HaroldC3 said:
This will be a great lens for a sunny day in the countryside. Yes, I know it will need good light, but we can still have our f/4, f/2.8 and faster for when the occasion demands it.
Let's have both options, providing that it has IS and IQ is up to the standard of recent Canon STM lenses.
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BTW, the patent does cover IS, though I am not exactly sure what it is implying!
[0039]
It may be made to correct image blur when a part of any lens group or lens group is moved so that it may have a vertical component to an optic axis, and a zoom lens vibrates in each working example. According to this, the whole optical system can be prevented from being able to perform vibration control, without newly adding the lens group for optical members, such as a variable vertex angle prism, or vibration control, and being enlarged.
What is meant by "the whole optical system can be prevented from being able to perform vibration control" for example?
[0039]
It may be made to correct image blur when a part of any lens group or lens group is moved so that it may have a vertical component to an optic axis, and a zoom lens vibrates in each working example. According to this, the whole optical system can be prevented from being able to perform vibration control, without newly adding the lens group for optical members, such as a variable vertex angle prism, or vibration control, and being enlarged.
What is meant by "the whole optical system can be prevented from being able to perform vibration control" for example?
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I have an EOS-M and enjoy it, but have no interest in this lens with the current body. The only uses I can think of for it are pretty pervy; i.e., grainy (high ISO) surveillance/PI shots or beach candids - and in the latter case good luck composing on the LCD in bright sunlight because you are shooting blind. If the new EOS-M has an EVF, greatly improved focusing (especially servo) and some kind of hand grip, on the other hand, this could be a great lens for casual wildlife use.
I really hope my prediction about the next EOS-M--that it will be essentially a reduced-depth Rebel body with an EVF and the 70D (or other DPAF) sensor--comes true.
I really hope my prediction about the next EOS-M--that it will be essentially a reduced-depth Rebel body with an EVF and the 70D (or other DPAF) sensor--comes true.
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I can speak from experience of testing lenses (native mount) on the telephoto end on the EOS M that this is all pointless unless they come up with a revised viewfinder system. The combination of glare in daylight (and the narrow aperture of this lens makes daylight shooting pretty much a must) and the disconcerting situation of trying to deal with screen refresh on the LCD makes shooting telephoto of anything moving a nightmare on the current M.
I like the overall concept, but for such a lens to become reality an improved body would first have to come. Someone mentioned that this lens would probably end up coming to market as f/6.3 (marketed maximum aperture) and I agree. Manufacturers tend to fudge these numbers a bit, and truthfully, most of us don't really know the difference when it comes to actually shooting.
I like the overall concept, but for such a lens to become reality an improved body would first have to come. Someone mentioned that this lens would probably end up coming to market as f/6.3 (marketed maximum aperture) and I agree. Manufacturers tend to fudge these numbers a bit, and truthfully, most of us don't really know the difference when it comes to actually shooting.
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neuroanatomist said:
some being the operative word
Where is the http://www.canonrumors.com/2014/04/patent-ef-m-22-46mm-f3-5-5-6/
or http://www.canonrumors.com/2014/01/patent-ef-m-18-40-pancake/
or http://www.canonrumors.com/2013/12/patent-16-120mm-f3-5-5-6-is-stm/
or http://www.canonrumors.com/2013/02/patent-canon-ef-14-f2-8-with-flourite/
all of which are claimed as patents for EF-M lenses
Yet none of the lenses they have released since the EOS M's launch have any corresponding patent filing...
Where is the patent filing for the EF-M 11-22, or EF-M 55-200 ?
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