Patent: Canon EF-S 20mm f/2.8 STM

[9VIII]

Right now the 40mm Pancake is probably my favourite lens, it's optically stellar. It's also pretty long for a crop sensor, if they can make a small 20mm lens as good as the 40mm Pancake then this is going to be one of the best crop lenses ever.
I do kind of wish it had IS, but if it's sharp and distortion free like the 40mm was then I'll take it.

I'm pleasantly surprised at the quality of optics Canon is selling in some of their budget lenses. The 40mm Pancake, the new 18-55 STM lenses (especially EF-M), and the 55-250 STM is almost as good as the original 100-400L (250mm on crop is equal to 400mm on full frame, so IQ should be directly comparable).
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=856&Camera=963&Sample=0&FLI=5&API=1&LensComp=113&CameraComp=453&SampleComp=0&FLIComp=7&APIComp=0

 

[preppyak]

Right now the 40mm Pancake is probably my favourite lens, it's optically stellar. It's also pretty long for a crop sensor, if they can make a small 20mm lens as good as the 40mm Pancake then this is going to be one of the best crop lenses ever.

Thing is, they basically already did this with the 24mm ef-s lens. Having used both, I cant tell the difference between the two at f/2.8. And I think the 24mm focuses faster.

I agree with others, if this was a 16mm prime to compete with what rokinon/samyang offers, I'd be interested. Or if it was a longer, cheaper ef-s prime (85mm or 100mm) it'd be interesting. At 20mm, it'd have to outperform the 24mm to be able to be priced higher.

Good that Canon is at least patenting EF-S designs though

 

[unfocused]

I'm with the "if it were just a bit wider" crowd. Something closer to a 24-28mm equivalent would be nice. I really don't understand Canon's EF-S prime strategy.

40 mm f2.8 (okay, I know it's not an EF-S...but.) = 64mm
24 mm f2.8 EF-S = 45 mm

and now a 20 mm, which would equal 32mm

They just seem like bizarre and not particularly useful focal lengths.

I'm glad they are doing some EF-S primes, but it seems like they would be a lot more useful if they were a little wider at the wide end and a little longer at the long end.

17-18 mm would get them a nice 28mm equivalent.
60 mm would get you close to a 100mm equivalent.

Together, they'd make a nice set of primes for the SL-2 when it comes out.

 

[quiquae]

I'm with the "if it were just a bit wider" crowd. Something closer to a 24-28mm equivalent would be nice. I really don't understand Canon's EF-S prime strategy.

40 mm f2.8 (okay, I know it's not an EF-S...but.) = 64mm
24 mm f2.8 EF-S = 45 mm

Your math is wrong. 24mm x 1.6 = 38.4mm. It's very close to the 40mm on full frame.

and now a 20 mm, which would equal 32mm

They just seem like bizarre and not particularly useful focal lengths.

32mm is fairly close to the 35mm prime focal length, which is a favorite of many. I agree that 64mm equivalent is a weird focal length; 40mm STM is more useful on full frame, I think.

I'm glad they are doing some EF-S primes, but it seems like they would be a lot more useful if they were a little wider at the wide end and a little longer at the long end.

17-18 mm would get them a nice 28mm equivalent.
60 mm would get you close to a 100mm equivalent.

EF-S 60mm already exists (f/2.8 macro). 17-18mm probably doesn't exist because it'd be relatively expensive and people wouldn't be inclined to buy expensive EF-S primes.

 

[unfocused]

I'm with the "if it were just a bit wider" crowd. Something closer to a 24-28mm equivalent would be nice. I really don't understand Canon's EF-S prime strategy.

40 mm f2.8 (okay, I know it's not an EF-S...but.) = 64mm
24 mm f2.8 EF-S = 45 mm 38mm

Your math is wrong. 24mm x 1.6 = 38.4mm. It's very close to the 40mm on full frame.

Yeah, I mis-typed I guess.

 

[Matthew Saville]

Why 20mm @ 1.6x? 32mm? This seems to be a little too close to the 24mm EF-S in utility, to be honest.

I'd rather have an 18mm or 15mm EF-S, even if the optics had to be a bit larger and $100-200 more.

Interesting that Canon is doing more new 2.8 primes than any other type. (I started counting new non-L primes with the 24 2.8 EF IS, the 28 2.8 EF IS, the 35 f/2 EF IS, and the 50 1.8 EF STM...)

I'm sure that most folks don't need a lens faster than 2.8, especially casual APS-C shooters, but I would still love to see more fast-but-affordable primes. A redesigned 50 1.4 EF STM and 85 1.8 EF STM are definitely needed, if Canon is going to stop the bleeding to Sigma Art.

 

[Maximilian]

I'm with the "if it were just a bit wider" crowd. Something closer to a 24-28mm equivalent would be nice. I really don't understand Canon's EF-S prime strategy.

40 mm f2.8 (okay, I know it's not an EF-S...but.) = 64mm
24 mm f2.8 EF-S = 45 mm 38mm

I am with you, at least in principle...

Seeing the quality per price ratio of the two pancakes and how they sell (and the supposed profit margin, because they are not "Made in Japan") I can understand Canon trying to continue this success story.

But 64 mm length makes it three times longer than the EF-S24/2.8STM and 1.6 times longer than the EF50/1.8STM.
EDIT: I made a mistake here in misunderstanding the patent. It is a pancake, see my post #32

So definitely not another pancake and for this size
I would have expected it to be at a FL of 15 to 17 mm but not 20 mm.

Maybe it's just a "dead" patent that will never get to the market and they decided for the EF-S24/2.8STM instead ...
(see also filing date 2013.12.6) 8)

 

[Antono Refa]

I would prefer to see a nice new 20mm 2.8L & not an ef-s lens.

Canon has L and non-L versions of the 24mm, 35mm, 50mm, 85mm, 135mm, and 200mm, 300mm, and 400mm lenses.

If Canon made a 20mm f/2.8 non-L over 20 years ago, and never bothered making a 20mm f/1.4L (or even f/2L), I guess it's because Canon knows there's no profit in it.

Then again, if Nikon made a new 20mm f/1.8 lens, maybe it's just a matter of not being as profitable or PRable as other lenses, e.g. the fisheye zoom and 11-24mm, so it just might pop up eventually.

 

[Maximilian]

... if they can make a small 20mm lens as good as the 40mm Pancake then ...

Hi 9VIII!

As I've noted befor the patent says the lens will be 64 mm long, so not small and definitely no pancake.
I don't know if it's possible to make a pancake lens at 20mm or shorter as good the EF-S 24.
But this patent is not that solution.
EDIT: I made a mistake here in misunderstanding the patent. It is a pancake, see my post #32

 

[insanitybeard]

Personally, I'd be interested in seeing an ultrawide EF-S prime, say in the region of 10-14mm to give an equivalent full frame focal length of 16-20mm. I've got the 10-22 EF-S and it's a good lens, but having recently bought a 16-35 f4 IS to use as a walkaround on my crop body, a small and compact ultrawide prime would make a nice compliment when 16mm isn't wide enough. I know, I know- I'm probably in a minority here and the focal length is covered by existing EF-S lenses, but if they're making a range of compact EF-S primes, why not an ultrawide?!

 

[9VIII]

... if they can make a small 20mm lens as good as the 40mm Pancake then ...

Hi 9VIII!

As I've noted befor the patent says the lens will be 64 mm long, so not small and definitely no pancake.
I don't know if it's possible to make a pancake lens at 20mm or shorter as good the EF-S 24.
But this patent is not that solution.

Thanks for clarifying that.

It's almost better that this one isn't a pancake. Honestly I was a little disappointed with the 24mm pancake because of the distortion and CA. I know it's not bad compared to most lenses, and especially considering the price, but I was really hoping the characteristics of the first Pancake would carry over to the second. Hopefully as a larger lens a 20mmf2.8 could have better correction (again, not that it's very common to see in that focal length, at any price).
I guess as soon as I start talking about buying multiple inexpensive prime lenses this really is where the Sigma 18-35 comes into its own (which I already have). It is distortion free at 24mm and at 18mm it's the same as the 24mm Pancake, and with the f1.8 aperture it's a no-brainer, except that you're giving up the portability and the freedom of using a $150 lens.

 

[Loswr]

... if they can make a small 20mm lens as good as the 40mm Pancake then ...

Hi 9VIII!

As I've noted befor the patent says the lens will be 64 mm long, so not small and definitely no pancake.
I don't know if it's possible to make a pancake lens at 20mm or shorter as good the EF-S 24.
But this patent is not that solution.

If you've noted this before, I must tell you've been wrong on more than one occasion. You're making the (very common) mistake of believing that this is a patent for a lens. Rather, what's being patented is really an optical formula for a lens. So, when the patent states, "Overall length of the lens: 64.00mm," understand that means the length all the way back to the image plane (sensor) as shown in the diagram. Look back at the patent for the EF 40mm f/2.8 (embodiment two), which lists the total length as 62.5mm.

Once you subtract the flange focal distance of 44mm from the overall length of this 20/2.8 design, you've got a physical lens that's 20 mm long (actually a bit longer, since filter threads protrude a bit in front of the optical formula).

So...yes, this is a pancake lens design.

 

[Maximilian]

... if they can make a small 20mm lens as good as the 40mm Pancake then ...

Hi 9VIII!

As I've noted befor the patent says the lens will be 64 mm long, so not small and definitely no pancake.
I don't know if it's possible to make a pancake lens at 20mm or shorter as good the EF-S 24.
But this patent is not that solution.

If you've noted this before, I must tell you've been wrong on more than one occasion. You're making the (very common) mistake of believing that this is a patent for a lens. Rather, what's being patented is really an optical formula for a lens. So, when the patent states, "Overall length of the lens: 64.00mm," understand that means the length all the way back to the image plane (sensor) as shown in the diagram. Look back at the patent for the EF 40mm f/2.8 (embodiment two), which lists the total length as 62.5mm.

Once you subtract the flange focal distance of 44mm from the overall length of this 20/2.8 design, you've got a physical lens that's 20 mm long (actually a bit longer, since filter threads protrude a bit in front of the optical formula).

So...yes, this is a pancake lens design.

Thank you for correcting me.

I didn't recognize that before. :-[
My mistake was reading "Overall length of the lens" and "BF" listed up seperately so I understood these two not as beeing BF a part of the lens but to be added up. So in my wrong conclusion the overall lengh of the optical formula would have been lengh + BF. But that was wrong. Sorry.

New conclusion:
If it's indeed another pancake, then the focal lengh is still too close to the EF-S 24mm.
(Still the question, if it's an alternative or an addition to it)
If it's the shortest FL possible for a pancake with good IQ, then Canon bring it on.
Otherwise make its FL shorter.

 

[TWI by Dustin Abbott]

If you've noted this before, I must tell you've been wrong on more than one occasion. You're making the (very common) mistake of believing that this is a patent for a lens. Rather, what's being patented is really an optical formula for a lens.....

Not only is true, but let me tell you as one that is occasionally privy to inside information from a few companies, some of these patents are actually filed as smokescreens while a slightly different lens (or mount) is being developed.

 

[Matthew Saville]

Personally, I'd be interested in seeing an ultrawide EF-S prime, say in the region of 10-14mm to give an equivalent full frame focal length of 16-20mm. I've got the 10-22 EF-S and it's a good lens, but having recently bought a 16-35 f4 IS to use as a walkaround on my crop body, a small and compact ultrawide prime would make a nice compliment when 16mm isn't wide enough. I know, I know- I'm probably in a minority here and the focal length is covered by existing EF-S lenses, but if they're making a range of compact EF-S primes, why not an ultrawide?!

If you want high-end lenses dedicated for your crop body, you bought the wrong system.

You should have bought a Ni- ...wait nevermind. They haven't built a high-end DX lens in generations either.

Maybe you should have bought a Pentax? Wait, they don't have anything wider/faster than 12mm f/4, either.

Okay so, buy a Rokinon 10mm f/2.8 or a Tokina 11-20mm f/2.8, and call it a day. Sorry.

But seriously folks, there are in fact tons of great crop-sensor options for ultra-wide zooms, if you're willing to consider third parties. Canon's 10-22 EF-S is no slouch either, for sharpness, in fact despite it falling short of the new 16-35 f/4, it actually beats most copies of the 16-35 2.8 and 17-40. Then there's the Rokinon 10mm f/2.8 if you're really into astro-landscapes, or there's the Tokina 11-16 or 11-20 if you want a zoom but still need 2.8, or there's the Tokina 12-28 if you want the most zoom range possible, and don't need a fast aperture. All of those lenses are so incredibly sharp, they give their full-frame equivalents quite a run for their money. So, unless you're absolutely in need of weather sealing, I'd say you're okay. It is a shame that Canon decided to deliver zero "L" lenses for EF-S, though, that was a corporate tactical error that I think their lens engineers are still shaking their heads over...

 

[LonelyBoy]

It is a shame that Canon decided to deliver zero "L" lenses for EF-S, though, that was a corporate tactical error that I think their lens engineers are still shaking their heads over...

I still swear I saw a line from a Canon rep, somewhere, that L means, among other things, it will work on all EOS cameras, so no EF-S L lenses will be produced.

Last time I said this someone brought up a fixed-lens bridge camera with a red ring and L on its lens, which is sort of a side point to a standalone lens.

 

[Loswr]

It is a shame that Canon decided to deliver zero "L" lenses for EF-S, though, that was a corporate tactical error that I think their lens engineers are still shaking their heads over...

I still swear I saw a line from a Canon rep, somewhere, that L means, among other things, it will work on all EOS cameras, so no EF-S L lenses will be produced.

Last time I said this someone brought up a fixed-lens bridge camera with a red ring and L on its lens, which is sort of a side point to a standalone lens.

There are also the 10x42L IS binoculars.

 

[LonelyBoy]

It is a shame that Canon decided to deliver zero "L" lenses for EF-S, though, that was a corporate tactical error that I think their lens engineers are still shaking their heads over...

I still swear I saw a line from a Canon rep, somewhere, that L means, among other things, it will work on all EOS cameras, so no EF-S L lenses will be produced.

Last time I said this someone brought up a fixed-lens bridge camera with a red ring and L on its lens, which is sort of a side point to a standalone lens.

There are also the 10x42L IS binoculars.

Interesting.

I'm still extremely comfortable in saying they'll never make an EF-S L lens.