# Roger Cicala - Variance in 50mm-58mm primes



## ahsanford (Jul 11, 2015)

As always, a fascinating read from Uncle Rog and his pal Olaf:
http://www.lensrentals.com/blog/2015/07/variation-measurement-for-50mm-slr-lenses

A few fascinating bits:


The new Canon 50mm f/1.8 STM (with its old optical formula) is off the charts for high consistency / low copy-to-copy variation:

_"The Canon 50mm f/1.8 STM was amazingly consistent, and I'm not sure why. It's a simple design, but so are several of the other 50mm lenses. I suspect there might be something different in the manufacturing process of this very new lens, but until I take one apart and look inside (we haven't yet) I'm only speculating."_


He has already run this data on 24mm primes, and in comparison, the 50mm primes are more consistent in general.


We have a habit of believing that newer lenses are more consistent than older ones. Roger's data -- granted, taken in a limited cross-section across many manufacturers -- would imply that this is not such a clear trend. In fairness, there was a very wide spread of simple 50s (Canon and Nikon budget f/1.8 designs) and very complex 50s (Sigma Art, Zeiss Otus 55) in this mix.

- A


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## ahsanford (Jul 11, 2015)

And this data _clearly_ proves, beyond any doubt, that this is what we need next:


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## sulla (Jul 11, 2015)

Wow, the Canon 50 1.8 STM is the most consistent lens of them all.

Consistency is only a virtue if you're not a screw-up. IQ-wise.

So yes, ahsanford, this is really what we want. Canon could have my money as well, if only they wanted it...


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## Mt Spokane Photography (Jul 11, 2015)

That's good to hear, I do expect that the AF design using the STM motor benefits from improved design and manufacturing processes.

However, I'd not want a 50mm f/'1.4 STM, I'd want pro level AF.


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## ahsanford (Jul 11, 2015)

Mt Spokane Photography said:


> That's good to hear, I do expect that the AF design using the STM motor benefits from improved design and manufacturing processes.
> 
> However, I'd not want a 50mm f/'1.4 STM, I'd want pro level AF.



Yep. I don't the red ring or magical draw of the 50L. I don't even need f/1.4 -- f/2 would serve me just fine.

I just need a proper/modern/reliable/fast/consistent *USM* 50mm lens that's 90% as sharp as the Art/Otus glass in half the size and weight. That's not an unreasonable ask.

- A


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## YuengLinger (Jul 11, 2015)

Ashanford continues his odd crusade against lenses faster than f/2.

Now that's consistent! :


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## ahsanford (Jul 12, 2015)

YuengLinger said:


> Ashanford continues his odd crusade against lenses faster than f/2.
> 
> Now that's consistent! :



Well played, sir. [Tips his cap.]

I'd love the 50 f/nooneknows IS USM to be f/1.4, but that would likely mean:


*Canon can't put out something the same speed as the Sigma Art and not try to compete against it optically.* (The current EF 50 f/1.4 USM does not compete against the Sigma Art from a host of optical perspectives.) That likely means abandoning the tiny basic optical design they have now. *That likely means the lens must get bigger and heavier*. Boo.


*A 50 f/1.4 IS USM would be very very attractive to all Canon users, including the 50L owners* -- a new Canon 50 will likely mop the floor with the 50L from a sharpness perspective (heck, the _current_ 50 f/1.4 USM already does that after f/2.8 ). Though sharpness isn't everything to the 50 prime crowd, not all 50L users are slamming that thing wide open, and as such I think such a sharp new lens would bite into 50L sales. Canon could combat this with either a higher asking price for the new lens (say $999) or _add a red ring, a weathersealing gasket and put a much higher asking price to it_. 

I guess, to try to sum that up: Canon isn't going to offer another 50 f/1.4 with IS on it as a pleasant little upgrade to the current 50 f/1.4 USM because such a lens creates price point problems for Canon and will not optically compete against the Sigma Art.

It _might_ (and I'm not certain) make more sense to make a killer alternative to the Sigma Art with a razor sharp 50 f/2 IS USM like the 35mm f/2 IS USM refresh of a couple years ago. Not making it f/1.4 makes it a different animal to the market and the natural comparisons to the Sigma Art will drop. It also would be smaller and lighter, which would be terrific. The pitch would be "90% as sharp as the Art, 50% as big, 50% as heavy, and this comes with IS." That would sell like hotcakes.

Truth be told, I just don't want a pickle jar for a staple walkaround lens. For me, there is immense value in smaller size + all the latest tech (internal focusing, modern USM, IS, solid build quality, etc.).

- A


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## YuengLinger (Jul 12, 2015)

My hands are not the steadiest, for sure, but I'd snap up a version II of the 50mm 1.2 L that had no more trouble with focus shift than the 85mm 1.2 L II, and slightly less tendency than the current 50 L to produce nervous bokeh in outdoor situations with trees/shrubs.

Could a 1.2 II have faster AF than the current? I really don't know. The elements are very heavy, the DoF so shallow. But if it had sharpness, accurate AF without focus shift complications, and slightly better f/2.8 - f/5.6 bokeh, even at double the Sigma Art's price, I think a lot of Canon shooters would buy it. A lot. Awareness of the beauty and importance of a dynamite 50mm in the quiver is higher than ever--thanks in part to Sigma!

With a fantastic 50mm 1.2, rarely would I be shooting above f/2.2 in low to medium light, so my shutter speeds are going to be fast enough where IS isn't crucial. I like IS, certainly, and it helps make the ef 16-35mm f/4 a joy (but I still plan to sell that if Canon releases a non-IS version in f/2.8, just as sharp across the frame).

But I don't want to be stuck at f/2! Too much potential, magic going wider at 50mm.

I'm so eager for an update of the 50mm 1.2 L. I only tried one copy of the Sigma Art. I had trouble with the AF on my 5DIII, but, beyond that, I wasn't so impressed with any aspect of the IQ other than sharpness. A sharp lens is very important to me, but I felt the Sigma Art had a dark character, so to speak, probably the vignetting and me not having learned to expose more to the right with it.

BTW, the Sigma 35mm Art is one of my favorite, lenses. Can't praise it enough. I just didn't catch the great feeling so many have for the 50mm Art, and I rarely see anything that impressive being done with it in online images.


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## siegsAR (Jul 12, 2015)

Old optic formula and consistency, on a cheap lens its a very good thing.


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## ScottyP (Jul 12, 2015)

I will never ever understand people who object to a great sharp lens based on a few ounces of weight. If a few inches length and a few ounces of weight are really the be all end all, then get a 40mm pancake and delight in it. All of my favorite lenses have some heft to them. Big deal unless you are free climbing with your cameras. 

If they could come out with a 50mm f/1.4 with IS and that was as sharp as Sigma, I promise Canon they would never, ever, ever, ever hear me bleating about the awesome lens being an inch too long and 3 ounces too heavy. Rather the contrary.

Same goes 3x if they would do that with an 85mm or a 135mm.


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## ahsanford (Jul 12, 2015)

YuengLinger said:


> Could a 1.2 II have faster AF than the current? I really don't know. The elements are very heavy, the DoF so shallow. But if it had sharpness, accurate AF without focus shift complications, and slightly better f/2.8 - f/5.6 bokeh, even at double the Sigma Art's price, I think a lot of Canon shooters would buy it. A lot.



I've shot the 50L and found that at f/1.2, my AF hit rate for frame filling head and shoulders portrait was relatively poor. At first, I thought it was the 50L commonly discussed 'finnicky AF' that needs some TLC through AFMA to dial in. But that wasn't it. The damn AF boxes (I have a 5D3) were sufficiently large that I'd occasionally grab a bridge of the nose or eyebrow and it threw things off a bit. (I was using off-center boxes and not recomposing, so it wasn't that.)

My point is, there comes a point that your DOF is so small that perhaps MF is the way to go...



YuengLinger said:


> With a fantastic 50mm 1.2, rarely would I be shooting above f/2.2 in low to medium light, so my shutter speeds are going to be fast enough where IS isn't crucial.



Must disagree, but that's a personal thing. For me, IS _is_ speed -- it makes everything better when you live on the dark end of lighting. 

I occasionally shoot concerts in wretched, wretched light, and you live in the ISO 6400 - 8000 neighborhood. If your subject isn't moving, IS makes any lens better as it's a stop for stop trade of IS stops for ISO stops, i.e. if I have a 3 stop IS lens, I can walk my ISO back 3 stops and still net the shot. That's massive when you are at the edge of the earth for acceptable high ISO quality.

But yes, quick glass can trump low light as well. If you are routinely working in good light, not shooting video, it's not a terribly long FL, etc. then IS is far less pressing of a need.

- A


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## ahsanford (Jul 12, 2015)

ScottyP said:


> I will never ever understand people who object to a great sharp lens based on a few ounces of weight. If a few inches length and a few ounces of weight are really the be all end all, then get a 40mm pancake and delight in it. All of my favorite lenses have some heft to them. Big deal unless you are free climbing with your cameras.
> 
> If they could come out with a 50mm f/1.4 with IS and that was as sharp as Sigma, I promise Canon they would never, ever, ever, ever hear me bleating about the awesome lens being an inch too long and 3 ounces too heavy. Rather the contrary.
> 
> Same goes 3x if they would do that with an 85mm or a 135mm.



You are not alone at all. From all my discussions on this lens, I'd say a good 80% of people would prefer the best instrument possible despite the weight, and 20% would willingly give up a stop of speed or possibly a little bit less on the IQ front for a smaller/lighter lens. 

Ask folks who own the Sigma 35 Art vs. the Canon 35 f/2 IS USM. It's a perfect case-study to peg who wants the best IQ vs. who values 'other things'. Neither are right, neither are wrong -- both are fine lenses -- but I think the percentage mix of who owns each lens would be telling (market-wise). 

- A


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## Mt Spokane Photography (Jul 12, 2015)

I'd love a 50mm f/1.2 that had near perfect optics, but that's not likely to happen, the cost and size might be out of sight. Its one thing to pay $12K for a big white, but for a 50mm to get a extra stop, it would not sell, not even at $3K. About the best we can hope for is a f/1.2 in the under 2K range with a substantial improvement, and hopefully truly excellent when stopped down. I've been surprised before, so there is hope.


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## TeT (Jul 12, 2015)

Amazon Prime Day; hoping to get a cheap 50 1.8 STM...


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## Hjalmarg1 (Jul 12, 2015)

YuengLinger said:


> Ashanford continues his odd crusade against lenses faster than f/2.
> 
> Now that's consistent! :


I found my 50mm 1.8 STM to be very consistent. Way better than all my previous Canon's 50mm (1.2, 1.4 & 1.8) lenses.
I don't use it much but when needed it offers very acceptable IQ. I'd also like to see a 50mm 1.4 IS lens (with similar quality of 35/2 IS) but, it will kill 90% of 50L sales, except from those who need weather resistant lenses. If Canon releases such a good lens they will take my money right away.


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## sulla (Jul 12, 2015)

ahsanford said:


> The damn AF boxes (I have a 5D3) were sufficiently large that I'd occasionally grab a bridge of the nose or eyebrow and it threw things off a bit. [...]
> My point is, there comes a point that your DOF is so small that perhaps MF is the way to go...



Indeed, the current 50 1.4 has already a very shallow DOF at portrait distances, not to speak of the 85 1.2.
And working with such shallow DOFs is very difficult. That's why I used to have my 5D3 set to single-point AF and even take the center only at this AF point (in the viewfindner it is the small point-like box within an AF-box), this very often is able to nail focus to where *I* want it. I don't know if this setting makes optimal use of the 5D3's capable AF-system, though.

But yes, using an aperture so large and a distance so short that the iris of an eye is in focus and the tips of the eyelashes are already out-of-focus is... not easy to work with. Not a keeper rate of 100% here as well...

But at larger distances wide apertures are extremely practical, think e.g. street photography at 1.4 in the night, not a big problem.

In my view the primes compete against the zooms: For me I decided a prime needs to be at least 1.4 to bring me a sufficiently big advantage over the 2.8 zooms to spend my money on it. I won't spend it on a 50/2 IS USM, but would do so on a 50 1.0 - 1.4 USM, as long as IQ competes with sigma. Size and weight do not matter for me, as the competition of the primes is against the zooms. If weight is the limiting factor, then there is always the EF 40.


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## sulla (Jul 12, 2015)

Mt Spokane Photography said:


> I'd love a 50mm f/1.2 that had near perfect optics, but that's not likely to happen, the cost and size might be out of sight.



Size not necessarily. You can do fantastic optics if you make widespread use of aspherical lens elements. And in this area technical progress is quick: Formerly it was necessary to grind aspherical lenses very very carefully and this was very expensive. Thus lenses like the EF 50 1.4 do not have aspherical lenses, and comparatively poor optics.
But in 2015 aspherical lenses can be simply moulded (at least smaller lenses can), and this makes it possilbe to put aspherical elements in small lenses like the EF 40.

So, I think it would be possible to improve upon the IQ of the current EF 50 1.0 / 1.2 / 1.4 by making ample use of aspherical lenses (which are not so expensive any more today) and special glass types (which are still expensive today).

Doesn't need to be retrofocus designs with twice the number of lens elements, size and weight.


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## Haydn1971 (Jul 12, 2015)

Personally, I'm seeing Canon gradually swamp the 50mm market with better products.

We currently have the;

50mm f1.2 - No one comes close on full frame for aparure size - Nikon can't do f1.2 in its current mount, I doubt Sigma would make a Canon only prime as fast.
50mm f1.8 STM - Cheap, well built, sharp - it's a bargain

So what are the issues moving forward;

IS hasn't yet been fitted to f1.4 glass
Buyers want better performance and IS
Buyers want faster than f1.8
The f1.2 is flawed
Macro ?

So where does that leave us (in my opinion) ?

Theres a market for a "better" optical lens with IS and macro abilities - This could be either f1.8 or f2.0 IS USM and I'd see customers being happy to pay £400 for such a lens
Theres a market for a Sigma Art killer 50mm f1.4 lens - I don't see this having IS, but I do see it being optically amazing - Customers would be happy to pay more than the current f1.2 for such a lens

Range moving forward...

50mm f1.8 STM
50mm f1.8/2.0 IS USM
Macro adapter for the above
50mm f1.4 L
50mm f1.2 L

I don't see the f1.2 being replaced anytime soon unless Sigma have a go at a Canon only version.


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## YuengLinger (Jul 12, 2015)

sulla said:


> ahsanford said:
> 
> 
> > The damn AF boxes (I have a 5D3) were sufficiently large that I'd occasionally grab a bridge of the nose or eyebrow and it threw things off a bit. [...]
> ...



My very sharp pupils/catch-lights rate with the 85mm 1.2 II is high. I never use center AF & recompose--only the AF point which suits the composition.

This took some time to learn, and I occasionally have to tweak AFMA. But the lens does its job very well.

Why would the same in a refreshed 50mm 1.2 be more difficult for Canon? Isn't DoF thinner at 85mm?


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## rfdesigner (Jul 12, 2015)

Haydn1971 said:


> Personally, I'm seeing Canon gradually swamp the 50mm market with better products.
> 
> We currently have the;
> 
> ...



Some very good points. Many people do seem to be forgetting the macro in dicussions

Thinking function first and looking at replacing the current lenses:

Macro and landscape.
50 f2.5 or 2.8 IS Macro USM built around a very flat image plane, very sharp even in ther corners and supremely so stopped down, at the expense of Boke, AF aimed at accuracy rather than speed

Portrait & Sport:
50 f1.4 USM with improved optics re flair and edge but not corner sharpness at 1.4, merely so-so stopped down, much improved contruction, not so close focussing and no IS, but lighting fast AF.

The 1.2L is a creative lens, so different again and not particulalry threatened by the above, but could still be updated.


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## ahsanford (Jul 12, 2015)

Haydn1971 said:


> Personally, I'm seeing Canon gradually swamp the 50mm market with better products.
> 
> Range moving forward...
> 
> ...



Interesting approach, but I see a three price point market, possibly four if the ancient 50mm f/2.5 1:2 macro is updated (I really consider that a different animal, though):


50 f/1.8 STM = inexpensive, sharp and light, but basically lacking any notable lens 'creature comfort' features -- it's only manual focus by wire, there's no distance scale, slower AF, non-sharpness metrics are not terribly well controlled (distortion, chromatic aberrations), etc.


Presuming the current 50 f1.4 USM is replaced --> 50 f/nooneknows IS USM, which takes everything from the line above but adds: 
A comprehensively better IQ
IS
Proper/modern/consistent/fast USM focusing
Internal focusing -- no externally sliding bits that can serve as a conduit for moisture or dust.
Much better build quality like the 24/28/35 IS refresh lenses
Still relatively small and light


The 50 f/1.2L or 50 f/1.2L II someday, which has everything the 50 f/nooneknows IS USM has, but is that extra bit faster, can be as big as needed for maximum IQ, and adds a red ring and a weathersealing gasket. With a Mk II version, Canon needs to decide if that lens can get by on reputation, 'magic', and that odd plane of focus meant for small DOF (i.e. some believe it's an _f/1.2 - f/2 only_ sort of lens and general 50 use is wasted with it) -- or if they want to modernize the lens to compete from a corner to corner sharpness perspective.

- A


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## StudentOfLight (Jul 12, 2015)

By f/4, the 50-STM can deliver excellent detail. (How much does that cost, $150?)

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=989&Camera=453&Sample=0&FLI=0&API=3&LensComp=917&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=4

With improved materials and build quality I guess you could realistically get 90% of the Otus performance by f/2 and stay below the $1000 mark. A 50/2 IS USM would hold advantages over the sigma in terms of hold-holdability, weight, cost (of manufacture), AF compatibility etc...



dilbert said:


> 90% as sharp as the Art/Otus would be sharper than the 50/1.2L...


Yes it would be. The 50L is definitely not the sharpest knife in the drawer.


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## StudentOfLight (Jul 12, 2015)

Hjalmarg1 said:


> YuengLinger said:
> 
> 
> > Ashanford continues his odd crusade against lenses faster than f/2.
> ...


Is the 50L really a popular lens? ???


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## ahsanford (Jul 13, 2015)

dilbert said:


> ahsanford said:
> 
> 
> > Mt Spokane Photography said:
> ...



Dilbert, the 20 year old 50 f/1.4 USM is _already_ sharper than the 50L!

Canon should be aiming at the Sigma Art as their bar for sharpness, not the 50L.

- A


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## sdsr (Jul 13, 2015)

ahsanford said:


> YuengLinger said:
> 
> 
> > Could a 1.2 II have faster AF than the current? I really don't know. The elements are very heavy, the DoF so shallow. But if it had sharpness, accurate AF without focus shift complications, and slightly better f/2.8 - f/5.6 bokeh, even at double the Sigma Art's price, I think a lot of Canon shooters would buy it. A lot.
> ...



I agree (though I tend to prefer MF anyway). Which is perhaps as good an excuse as any to note that the FD 50L and FD 85L are smaller, lighter, have much nicer MF mechanisms and are much less expensive than their AF equivalents (more attractive too, I think), and hope that Canon eventually cough up a FF mirrorless camera to make them easy to focus (meanwhile there's the Sony a7 line...).


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## ahsanford (Jul 13, 2015)

StudentOfLight said:


> Is the 50L really a popular lens? ???



It is, but it depends on who you are. You've got three different camps on the 50L (based on a few dozen threads I've chatted with folks about them):

1) Some believe there is some unquantifiable draw and magic about the 50L. That could be tied to its large aperture or it's nutty not-quite-plane of focus that is built for bokeh, but many would say the images that lens produces can't really be accomplished with another lens. 

2) There are those who recognize some of the 50L's flaws, but they only use Canon first party gear and facts are facts -- it's Canon's best overall 50mm prime. Iffy sharpness be damned, it has the fastest and least hunt-y AF of all Canon 50 primes, and it is the best built.

3) Folks who principally care about sharpness -- something you can readily measure and compare -- can clearly see the 50L is outclassed by a number of lenses: Canon's own 50 f/1.4 USM, _both_ Sigma 50 primes (Art and its predecessor), 3 Zeiss MF lenses, etc. However, all of those lenses have some drawbacks of their own, principally with quality of bokeh, reliability/consistency of AF (or _presence of AF_ for the MF lenses).

So there is no clear top dog for 50 primes:

The Zeiss Otus (technically a 55mm) is owned by a very very small subset of people. It is spectacular on virtually every front, but being an MF lens + being a $4k lens limits its overall appeal. It's also a 2.3 lb pickle jar of a lead weight, but I'm guessing if you have the money for one, you don't that mind that so much.

The Sigma 50 Art is the popular 'best general use 50' today as it is a solid 9/10 at _everything_, but there are a number of reports of inconsistent AF that frustrate some users. It's also comically big and heavy -- on the order of a 24-70 f/2.8 zoom.

I still use my 50 f/1.4 USM because it's the sharpest 50 Canon sells at the apertures I shoot, and I got lucky and have a decent AF copy that may hunt a bit but almost always eventually confirms. It's also a fairly unassuming little lens I can use for candids that won't get a party or gathering of friends all gunshy. It also leaves an aggregate body+lens footprint small enough to allow me to bring my camera more places more often (i.e without large padded coffin of a camera bag). It's not the best 50, I admit -- but it's the best 50 _for me_.

- A


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## HighLowISO (Jul 18, 2015)

I have the Sigma 50mm f/1.4 Art lens and as people say it's very nice optically and physically, with a fair price. 

Still I think Canon could produce a 50mm f/1.4 update and not have to worry about not matching or exceeding the Sigma optically on every characteristic. They 50mm f/1.2L is still a fin lens and for some is the better choice for portraits, the Sigma is more general purpose but it's not f/1.2 so Canon has a few differentiators in their top model and being a "Canon" lens is one of them.

So on the 50mm f/1.4 update, ring USM should be a given, this might affect the size a bit. Or maybe to keep the lens small they will introduce a new dual or tripple linear motor of some-type and that will keep the lens well suited for video. So they can look at a few features as differentiators and as long as the size is kepts under control I don't think people will expect it to exceed the Sigma Art.

Size/Weight - important these days with mirrorless competition, and trends.
AF by Canon- go for precision and performance. 
IS - if they managed to get IS in it while maintaining size/weight and reasonable oprical performance then it seems like a large part of the market would go for it.
Price - as reasonable as the Sigma Art is for the quality, some just don't want to pay that much. With the expected market for the lens, maybe Canon could have at-least two of the above and keep the price no more than $500US. There are some good composites that could be used in the manfacturing to keep weigth and costs down, and with the sub-assembly construction Canon has been using lately parts of the lens could manufactured maybe outside of Japan. Seems like with the high resolution sensors and digital in general the newer lenses are assembled with a bit tighter tollerances so they probably have some new QC steps or machines in final assembly.
Built-in Hood?

Will it happen... well luckily now with the Sigma I can wait, and I really probbaly don't need any update from Canon as I tend to also use an APS-C mirrorless often now for 50mm equivalent so I can carry the Canon with a large telephoto.


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