# Teardown: Canon RF 70-200mm f/2.8L IS USM



## Canon Rumors Guy (Dec 10, 2019)

> Our friends at Lensrentals.com have done what a lot of us wanted to see done, and that’s a teardown of the brand new Canon RF 70-200mm f/2.8L IS USM.
> *From Lensrentals.com:*
> There are some of you who are going to scream about how you want metal lenses. OK, Boomer, go get you a metal lens and show us how strong you are. On every other 70-200mm lenses we’ve disassembled, there are multiple metal parts that we can bend with our fingers. There’s not a damn thing we can bend with our fingers in this bad boy. This is going to hold up better than a metal lens, it’s probably sturdier, and it weighs far less.
> I haven’t tested it optically. I haven’t even shot with it. But after looking inside it, I want it. The engineering in here is pure art. And even I, the person who mocks construction at any chance I get, can’t find anything to complain about...



Continue reading...


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## Braintoggle33 (Dec 10, 2019)

Why so angry?


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## Tom W (Dec 10, 2019)

Impressive construction. Always enjoy when Roger and company tear down a lens or camera. It's nice to know, also, that they can put them back together again.


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## bbb34 (Dec 10, 2019)

That is delightful lens porn!


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## Del Paso (Dec 10, 2019)

Once again, this teardown demonstrates that some of us should better wait for reliable facts before criticising or incensing a new product...


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## Maximilian (Dec 10, 2019)

Somehow this great piece of engineering makes me wanting this lens  damn me gearhead 

Now let's see what Roger measures out of the optics...


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## Cesar (Dec 10, 2019)

When not extended "it’s only 5.75 inches long and weighs only 2.35 pounds."
How about the weight when extended?


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## prodorshak (Dec 10, 2019)

Cesar said:


> When not extended "it’s only 5.75 inches long and weighs only 2.35 pounds."
> How about the weight when extended?


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## cayenne (Dec 10, 2019)

Canon Rumors Guy said:


> OK, Boomer....



K-O Millenial...


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## Del Paso (Dec 10, 2019)

Maximilian said:


> Somehow this great piece of engineering makes me wanting this lens  damn me gearhead
> 
> Now let's see what Roger measures out of the optics...


And I naively thought 2019 was expensive, 2020 will drive me into bankrupcy-ditch.


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## YuengLinger (Dec 10, 2019)

Very informative. Enlightening, even!

I do have a great relationship with my ef 70-200mm f/2.8L IS II. But it doesn't like the EOS R, mostly because of balance issues. Almost like they weren't made for each other.  I have a very hard time getting sharp shots with the combo *in vertical orientation*, though other lenses on the R are great, and the ef 70-200mm on my 5D IV is great. But, wow, do my hands get awkward and wobbly with the R and the ef version.

If this is beautifully balanced on the R, does this give us an indication that future R bodies will have similar ergonomics?


But as long as I have my 5DIV, I cannot justify ditching the ef lens.



Great teardown and discussion of what hopefully is a great new lens.


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## SteveC (Dec 10, 2019)

prodorshak said:


> View attachment 187769




Aaaah, but you forgot the three pounds of dust that get sucked in every time.

Or so I am told is true for every extending "dust pump" lens.

(And yes, I'm being sarcastic.)


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## Drcampbellicu (Dec 10, 2019)

Canon is the best lens maker by a mile



Canon Rumors Guy said:


> Continue reading...


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## mb66energy (Dec 10, 2019)

Up to now I wasn't very much interestet in the R system but after ordering an RP with RF 35 @ just over 1000 EUR (just the packet is hanging on a postal hub, hopefully it will come in the next days or week) I couldn't resist. Added an FD2RF adapter to reuse my old FD glass and to check if I will keep it or sell it.

Checking the specs I found out that the RP is more or less the M50 mark ii I was searching for (two dials, Linear PCM, servo AF with eye detect and some minor but convenient tweaks) and if you strip down the price of that offer to a body only price it was as expensive as an M50.

While I will keep the M50 with the EF-M 32 which is a unique combination in terms of portability and IQ the RP with the RF 70-200 would make a great companion with large aperture, IS and similar weight compared to the f/4 70-200 IS + EF2RF adaptor. And it's more compact than the EF variant (while having maybe a similar volume).

TDP has it's standard comparison photos and from what I see the RF 70-200 is a very good lens - but it's not easy to compare because of the different resolutions of EOS R and 5Ds / 1Ds mark iii ...








Canon RF 70-200mm F2.8 L IS USM Lens Image Quality


View the image quality delivered by the Canon RF 70-200mm F2.8 L IS USM Lens using ISO 12233 Resolution Chart lab test results. Compare the image quality of this lens with other lenses.




www.the-digital-picture.com




The EF III seems to be a tad better at 70mm while the RF wins @ 200mm but this is a very rough estimate due to the different sensor resolutions.

Factoring in size, weight and the great MFD / max. reproduction ratio of 0.23 it might be a very good "to go" lens!


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## David - Sydney (Dec 10, 2019)

SteveC said:


> Aaaah, but you forgot the three pounds of dust that get sucked in every time.
> 
> Or so I am told is true for every extending "dust pump" lens.
> 
> (And yes, I'm being sarcastic.)


Interesting comment from Roger!
"Before we start, though, let’s get the extending barrel discussion out of the way. Some of you HATE extending barrel lenses. That’s cool; don’t get one. Some of you like to call them dust pumps. That’s cool, too, although it’s incorrect. (We take care of over 20,000 lenses. The most common ‘dusters’ among current lenses all happen to be primes that don’t zoom at all.) "


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## SteveC (Dec 10, 2019)

David - Sydney said:


> Interesting comment from Roger!
> "Before we start, though, let’s get the extending barrel discussion out of the way. Some of you HATE extending barrel lenses. That’s cool; don’t get one. Some of you like to call them dust pumps. That’s cool, too, although it’s incorrect. (We take care of over 20,000 lenses. The most common ‘dusters’ among current lenses all happen to be primes that don’t zoom at all.) "



I had that very thing in mind when I wrote.


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## dominic_siu (Dec 10, 2019)

Yesterday I brought the RF70200 to take some test shots, it’s very compact when stored and lightweight. I didn’t use 70200 2.8 of any EF version when I used DSLR, this is my first 70200 2.8 and I delivers great result, just love it!


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## Sator (Dec 11, 2019)

The most important thing in this article was this statement: "Canon claims that the shorter back focus distance with a wider opening allows them to place larger elements closer to the sensor to achieve this. The fact that the rear element is a large aspheric with subwavelength coating, and that the other rear elements are large, supports this".

Canon stated that they experimented with copying Sony by retro-converting their APS-C dimension M mount (almost identical in flange distance and diameter to the Sony E mount) into a 35mm format mount, but they found that the cramped APS-C dimension mount forced engineers to place heavy lens elements on the end of the lens and that you couldn't place them close to the sensor as you could with a large diameter mount (with a "wider opening" as Roger puts it). You also needed extra corrective elements to get the light to bend unnaturally into the sensor corners. These diagrams come from a presentation by Canon at the time the EOS R was released (I have added my own translation to Canon's captions).







So it's not just about being more compact in size but also less front heavy and imbalanced.

It took Canon longer to enter the 35mm mirrorless market because they had to build their 35mm mirrorless system from scratch. The Sony hare only managed to get in front of Canon and Nikon by taking a dirty little shortcut in retro-converting an APS-C mount into a 35mm mount, but this has left a critical vulnerability that the tortoises are going to slowly exploit. Are Sony ******* yet?


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## navastronia (Dec 11, 2019)

Sator said:


> The most important thing in this article was this statement: "Canon claims that the shorter back focus distance with a wider opening allows them to place larger elements closer to the sensor to achieve this. The fact that the rear element is a large aspheric with subwavelength coating, and that the other rear elements are large, supports this".
> 
> Canon stated that they experimented with copying Sony by retro-converting their APS-C dimension M mount (almost identical in flange distance and diameter to the Sony E mount) into a 35mm format mount, but they found that the cramped APS-C dimension mount forced engineers to place heavy lens elements on the end of the lens and that you couldn't place them close to the sensor as you could with a large diameter mount (with a "wider opening" as Roger puts it). You also needed extra corrective elements to get the light to bend unnaturally into the sensor corners. These diagrams come from a presentation by Canon at the time the EOS R was released (I have added my own translation to Canon's captions).
> 
> ...



I love this diagram and explanation, but Sony _has_ stated repeatedly that the mount diameter doesn't limit their lens design. I think they also claimed that the E mount could theoretically take f/0.95 lenses, but that they didn't have any planned. Would an f/0.95 lens also feature huge elements at the front of the lens and smaller ones at the rear, thus changing/throwing off the balance on the body? According to what you've posted, quite possibly.


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## brad-man (Dec 11, 2019)

If /when I retire my 5DIV and switch to R series, I hope they give the same treatment to an RF 70-200 f/4L IS. The performance/size/weight ratio would be most gratifying.


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## Cochese (Dec 11, 2019)

navastronia said:


> I love this diagram and explanation, but Sony _has_ stated repeatedly that the mount diameter doesn't limit their lens design. I think they also claimed that the E mount could theoretically take f/0.95 lenses, but that they didn't have any planned. Would an f/0.95 lens also feature huge elements at the front of the lens and smaller ones at the rear, thus changing/throwing off the balance on the body? According to what you've posted, quite possibly.


Would you really expect Sony to admit any fault with their mount though? Not likely. Theoretically they can make just about any lens, but they don't have the same freedom of design. Which we'll see as time goes on. There's a good reason Nikon's mount jumped by nearly 10mm from the DSLR to mirrorless.


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## Sator (Dec 11, 2019)

Cochese said:


> Would you really expect Sony to admit any fault with their mount though? Not likely. Theoretically they can make just about any lens, but they don't have the same freedom of design.



Exactly. A Sony engineer gave a public talk in Japan in which he admitted that there was a heated debate within the company as to whether they should retro-convert their APS-C E mount into a 35mm format mount. That suggests that there were almost certainly dissenters amongst the Sony engineers who questioned the wisdom of doing this. It is quite possible (although this is speculative) that the decision to proceed with a 35mm format mount with APS-C dimensions was made more by the marketing department wanting to draw first blood over Canon and Nikon and that the engineers were overruled.

Naturally, the marketing department at Sony will not admit to any errors. However, it is rather damning to think that three firms founded APS-C mirrorless mounts around the same time: Canon (M mount), Sony (NEX/E mount), and Fuji (X mount)—but only one of these companies has retro-converted their APS-C mount into a 35mm format mount. Other firms could have designed a 35mm mount with APS-C dimensions but none have. Leica hasn't, nor has Sigma, Panasonic, Canon, or Nikon. That's a lot of engineers from lots of firms across the world to shun the Sony approach. Sony is out on a limb, totally isolated, leaving its marketing department to predictably spin the supreme wisdom of their decision.

Sadly, I rather fear that the success of the Sony FE mount represents the success of marketing strategy over good engineering.


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## SecureGSM (Dec 11, 2019)

"... This ‘glass at the rear’ design is what allows this lens to be both shorter and lighter than other 70-200mm lenses...".

the above suggests that RF 400 F2.8 lens can be much lighter than EF 400 F2.8 III. I am thinking around 2.3kg ???


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## Sator (Dec 11, 2019)

navastronia said:


> I love this diagram and explanation, but Sony _has_ stated repeatedly that the mount diameter doesn't limit their lens design.



Of course, Sony would claim this. Sony issued this denial only with respect to the particular concern that the FE mount would not be able to support ultra-wide apertures. That is NOT the criticism of an ASP-C dimension 35mm format mount that Canon has come up with. The Canon internal R&D department state that they found that if they retro-converted their M mount into a 35mm format mount that it had negative repercussions on the ergonomics of the lens, making it front heavy, and requiring extra corrective elements i.e. a small and cramped mount means larger, more expensive, imbalanced and front heavy lens.

Fuji has also come up with similar criticism of the Sony FE mount based on what they call the "value angle" which simply implies that the dimensions of the FE mount hinder good lens design. This has also been recently the subject of a thread here:









Fujifilm thinks the Canon EF-M mount is the best in the business for ease of lens design


Here's an interesting one that came out of the recent X system summit by Fujifilm. They came up with something that is called the "value angle" when talki



www.canonrumors.com





Clearly, it was hardly in Fuji's self-interest to come up with this concept (although it won't stop Sony fanboys from dismissing it as self-interested Fuji propaganda). But it probably represents a fair consensus statement of what engineers within the optics industry overall think of the Sony FE mount.

Again, if retro-converting an APS-C mount into a 35mm format mount was such a fantastic idea (as Sony will predictably claim) then Canon would not have bothered spending a lot of time and money starting a new mount system from scratch, with Nikon independently coming up with its Z mount with almost an identical mount diameter to Canon.


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## Sator (Dec 11, 2019)

One more critical point. It is in Sony's vested self-interest to claim that a 35mm mount with APS-C dimensions presents no optical engineering limitations. It is in Canon's vested self-interest to claim that their time and effort in developing a new 35mm mirrorless mount with optimal dimensions has been worth it and the result of a superior engineering decision. Which should we believe?

The answer is we need an independent assessment of these rival claims. That's why Roger's statement, which I repeat again, is so important:

_Canon claims that the shorter back focus distance with a wider opening allows them to place larger elements closer to the sensor to achieve this. The fact that the rear element is a large aspheric with subwavelength coating, and that the other rear elements are large, supports this._

This should not be read as Roger definitively endorsing Canon's engineering department, but it is a tentative first step towards that. I think, watch this space.

As an aside, this is bad news for those interested in third party lenses for the RF mount. The Sigma CEO has said that they need to make their lenses work for all mounts starting with the most restrictive one, which in this case is the Sony FE mount. That means that Sigma won't be able to place large lens elements near the sensor for any of their native mirrorless 35mm format lenses. The limitations of the Sony FE mount will be endemic to both the Canon and Nikon versions of their mirrorless lenses. Ouch.


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## SecureGSM (Dec 11, 2019)

actually, Roger then went to say:

This ‘glass at the rear’ design is what allows this lens to be both shorter and lighter than other 70-200mm lenses.

which is quite a statement. so here is the confirmation you were looking for. right there.


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## koenkooi (Dec 11, 2019)

Sator said:


> [..]
> As an aside, this is bad news for those interested in third party lenses for the RF mount. The Sigma CEO has said that they need to make their lenses work for all mounts starting with the most restrictive one, which in this case is the Sony FE mount. That means that Sigma won't be able to place large lens elements near the sensor for any of their 35mm format lenses. The limitations of the Sony FE mount will be endemic to both the Canon and Nikon versions of their mirrorless lenses. Ouch.



I wonder if they'll stick with that for their L mount designs and if not, will they offer them in RF and Z and leave out FE?


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## Larsskv (Dec 11, 2019)

koenkooi said:


> I wonder if they'll stick with that for their L mount designs and if not, will they offer them in RF and Z and leave out FE?



Good question. They have to consider making a lens that isn’t compatible with Sony, if the design advantage by ditching Sony is significant...


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## geffy (Dec 11, 2019)

YuengLinger said:


> Very informative. Enlightening, even!
> 
> I do have a great relationship with my ef 70-200mm f/2.8L IS II. But it doesn't like the EOS R, mostly because of balance issues. Almost like they weren't made for each other.  I have a very hard time getting sharp shots with the combo *in vertical orientation*, though other lenses on the R are great, and the ef 70-200mm on my 5D IV is great. But, wow, do my hands get awkward and wobbly with the R and the ef version.
> 
> ...


 A fellow pro use the grip and swears it makes it more like a dslr but its more weight and a single battery life is awesome anyway


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## YuengLinger (Dec 11, 2019)

geffy said:


> A fellow pro use the grip and swears it makes it more like a dslr but its more weight and a single battery life is awesome anyway



I thought about the grip, and I like the idea of more mass to balance longer ef lenses (which have the extra length from the adapter). But I'm not sure, when shooting in vertical orientation, my thumb would reach the upper-right part of the back LCD for Touch and Drag. Somebody else on this forum suggested a firmware update could switch the active AF area of the LCD (like the AF point can automatically switch in portrait orientation), but as yet it is only a suggestion.

I'm not taking away anything from the ef 70-200mm f/2.8L IS II. It's great. Some of my best shots. But it just gets wobbly when vertical on the R--in my small-medium size hands.


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## jdavidse (Dec 12, 2019)

This is the reason I sold my EF 70-200 and and got the RF 70-200. While a great lens, the length and unwieldliness on the R was just a bridge too far. The RF is night and day a better lens to handle, and of course it comes with me a lot more often.

As for the 5D IV, I’m keeping it for now but I don’t think it’s as strong as the R for the uses I use the 70-200 for. Tracking, focus speed, sharpness are all a lot better on the R with the RF lens. It’s like night and day.

All that said, the RF is flawed- it has the front focus issue at MFD. Mine has been to Canon and back but they won’t admit to finding anything. I hope we will see a firmware fix in the near future; I am taking a gamble in keeping the lens because MFD isn’t something I shoot at a whole lot.



YuengLinger said:


> Very informative. Enlightening, even!
> 
> I do have a great relationship with my ef 70-200mm f/2.8L IS II. But it doesn't like the EOS R, mostly because of balance issues. Almost like they weren't made for each other.   I have a very hard time getting sharp shots with the combo *in vertical orientation*, though other lenses on the R are great, and the ef 70-200mm on my 5D IV is great. But, wow, do my hands get awkward and wobbly with the R and the ef version.
> 
> ...


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## Optics Patent (Dec 12, 2019)

I finally switched from Nikon to Canon because of this lens. Five figures of Ebay sales in the last month. 

This lens at 70mm is a great one to have around the house and kids. A totally different mission than an old 70-200 horse's leg. A 35mm pancake (or wide zoom) to supplement, and this could be the new "main zoom." Ideal wedding lens?


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## cayenne (Dec 12, 2019)

Optics Patent said:


> I finally switched from Nikon to Canon because of this lens. Five figures of Ebay sales in the last month.
> 
> This lens at 70mm is a great one to have around the house and kids. A totally different mission than an old 70-200 horse's leg. A 35mm pancake (or wide zoom) to supplement, and this could be the new "main zoom." Ideal wedding lens?



Impressive on the sales!!
I'd be very interested in seeing your work.....any links?


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## deletemyaccount (Dec 13, 2019)

I received this message this morning on my cellphone while doing a quick search. Take it for what it's worth.









Canon Users are Reporting That Their Brand New RF 70-200mm f/2.8 Has Focus Issues


Multiple Canon EOS R users on both the Fred Miranda and DPReview forums are reporting front focusing issues with their brand new RF 70-200mm f/2.8 lenses,




petapixel.com


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## Optics Patent (Dec 13, 2019)

Sator said:


> View attachment 187771
> 
> 
> View attachment 187770



These images are both helpful and maddening (I get the same in my optics patent law practice). Ray traces do NOT remain straight when passing through curved surfaces. The only qualitatively correct ray is that little red one. The rest are all wrong.


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## Optics Patent (Dec 13, 2019)

cayenne said:


> Impressive on the sales!!
> I'd be very interested in seeing your work.....any links?



I'm not selling photos. I'm selling Nikon equipment. 

I'm an amateur shooter who has been published and won awards, but my photography is personal family stuff mostly. I'm a patent lawyer who specializes in part in optics, and also an inventor in the digital photography space.


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## geffy (Dec 13, 2019)

camerabug said:


> I received this message this morning on my cellphone while doing a quick search. Take it for what it's worth.
> 
> 
> 
> ...


According to tomy northrup this is just a fact of life with focusing and fast lenses, he has a workaround, maybe in the future things might be perfect but photography is a practical thing and if you pixel peep and complain you will miss taking that picture


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## SecureGSM (Dec 14, 2019)

geffy said:


> According to tomy northrup this is just a fact of life with focusing and fast lenses, he has a workaround, maybe in the future things might be perfect but photography is a practical thing and if you pixel peep and complain you will miss taking that picture


Oh, you cannot be serious... what a bucket of bollocks. This has nothing to do with practicality. This is a US$2600 zoom lens.


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## koenkooi (Dec 14, 2019)

SecureGSM said:


> Oh, you cannot be serious... what a bucket of bollocks. This has nothing to do with practicality. This is a US$2600 zoom lens.



The use of 'Northrup' should have made that clear


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## geffy (Dec 14, 2019)

SecureGSM said:


> Oh, you cannot be serious... what a bucket of bollocks. This has nothing to do with practicality. This is a US$2600 zoom lens.


I wonder if canon do not do a "fix" might cause you to question your opinion and improve your skills, the problem is probably with the technology which will improve as the body is just not up to the task and hence the lens might need the r2 or r3 to show its capabilities


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## Mikehit (Dec 14, 2019)

Sator said:


> Of course, Sony would claim this. Sony issued this denial only with respect to the particular concern that the FE mount would not be able to support ultra-wide apertures. That is NOT the criticism of an ASP-C dimension 35mm format mount that Canon has come up with. The Canon internal R&D department state that they found that if they retro-converted their M mount into a 35mm format mount that it had negative repercussions on the ergonomics of the lens, making it front heavy, and requiring extra corrective elements i.e. a small and cramped mount means larger, more expensive, imbalanced and front heavy lens.
> 
> Fuji has also come up with similar criticism of the Sony FE mount based on what they call the "value angle" which simply implies that the dimensions of the FE mount hinder good lens design. This has also been recently the subject of a thread here:
> 
> ...




The issue is not the veracity of these comments, but under what circumstances the differences in latitiude for lens design really matter to the key market(s). Yes, there will be some who will revel in the possibility that having a lens closer to the sensor permits better edge-to-edge sharpness, and yes some will love the opportinuties for more compact lens design (let's not forget that newer technology is enabling smaller, lighter lens designs anyway. But how many people will think the difference(s) is important enough to differentiate between marques? My guess is not a lot.

I am just as interested in the fact that Canon has increased the number of electrical contacts in the mount - that suggests that they have some serious technological advances planned, possibly some of those years from now. Maybe those advances are still in the theoretical stage and the contacts are there 'just in case', maybe those advances are on the drawing board or already in place?


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## SecureGSM (Dec 15, 2019)

geffy said:


> I wonder if canon do not do a "fix" might cause you to question your opinion and improve your skills, the problem is probably with the technology which will improve as the body is just not up to the task and hence the lens might need the r2 or r3 to show its capabilities


1. The fix is pre-announced.
2. What do you know about my skills? Seriously, this is hilarious.


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## geffy (Dec 15, 2019)

SecureGSM said:


> 1. The fix is pre-announced.
> 2. What do you know about my skills? Seriously, this is hilarious.


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## geffy (Dec 15, 2019)

Any fix to focusing tends to open up a problem elsewhere so it remains to be seen how satisfactory it is and whether its partly a camera issue in the long run
nd


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## SecureGSM (Dec 15, 2019)

geffy said:


> Any fix to focusing tends to open up a problem elsewhere so it remains to be seen how satisfactory it is and whether its partly a camera issue in the long run
> nd



We Know nothing regarding root of the issue here nor We understand what the solution will be proposed. 
Can you focus on subjects you truly understand instead?


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## geffy (Dec 15, 2019)

SecureGSM said:


> We Know nothing regarding root of the issue here nor We understand what the solution will be proposed.
> Can you focus on subjects you truly understand instead?


hee hee


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## justaCanonuser (Dec 19, 2019)

This is my personal love letter to Canon's engineering :

I love to read Roger Cicala's blog, in particular before making a new investment. Over many years it does tell one story which IMO is more important than any lab tests: on the prosumer/pro level, Canon delivers exceptional quality. As a birder/wildlife photographers (amateur), my wife and I really mistreat our gear, we use it in heavy rain in the mountains, in sand & saltwater spray on winter shores etc., and I always experienced: my Canon simply works. Once my then already old and therefore a bit misused 7D swallowed sand in its thumb wheel, it crunched for a few weeks a bit and then the sand was milled out, but the camera never gave up to shoot. And my old battered EF 500mm crashed on rocks, was crusted with salt, banged against trees, but it still works flawlessly. Shooting side by side with comparable cameras and lenses, my wife's Nikon gear, unfortunately, proved many times to be much less reliable, we had a lot of repair so far. 

This is the main reason why I still use Canon, despite the fact, that they lost some of their technical leadership on the camera side within the past ten years.


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