# Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II, EOS



## Canon Rumors Guy (Aug 9, 2017)

```
As with <a href="http://www.canonrumors.com/how-to-fix-weird-visual-behaviour-with-pairing-the-eos-1d-x-mark-ii-sigma-lenses/">most new Canon DSLR releases</a>, there are some third party lenses that may present the odd vignette when “Lens Aberration Correction” is turned on with various Canon DSLRs.</p>
<p><strong>From Sigma:

</strong>We have found that some SIGMA interchangeable lenses for CANON are not fully compatible with CANON EOS 6D Mark II released on August 4th, as well as EOS 9000D (77D), EOS Kiss X9i (Rebel T7i) and EOS Kiss X9 (Rebel SL2).</p>
<p>When certain lenses are attached to these cameras and the “Lens aberration correction” function on these cameras is set to “Enable” for Live View shooting, an error would occur.</p>
<p>Please set the “Lens aberration correction” function of the cameras to “Disable” when using SIGMA’s interchangeable lenses for CANON.</p>
<p>In addition, please also refer to other notice below, related to the usage of EOS mount SIGMA lenses on Canon cameras.</p>
<p><!--more--></p>

<p><b>Phenomenon

</b>When the lenses listed below are used on EOS 6D Mark II, EOS 9000D, EOS Kiss X9i, or EOS Kiss X9 and the “Lens aberration correction” function on the camera is set to “Enable” for Live View shooting, an error would occur.</p>
<p><b>Products Affected</b></p>
<ul>
<li>SIGMA 30mm F1.4 DC HSM | Art</li>
<li>SIGMA 30mm F1.4 EX DC HSM</li>
<li>SIGMA 35mm F1.4 DG HSM | Art</li>
<li>SIGMA 50mm F1.4 EX DG HSM</li>
<li>SIGMA 85mm F1.4 EX DG HSM</li>
</ul>
<p><b>Usage Notice for customers who are using EOS mount SIGMA lenses on CANON cameras

</b>When using the SIGMA lenses for CANON, “Peripheral illumination correction”, “Chromatic aberration correction”, “Diffraction correction” as well as “Distortion correction” from the “Lens aberration correction” function of the camera are not supported. Therefore, we recommend you to set them to “Disable”.</p>
<p>If those functions are set to “Enable”, the performance of the lenses may not be accurate.</p>
<p>For further information, please contact your nearest authorized <a href="http://www.sigma-global.com/en/about/world-network/" target="_blank" rel="nofollow noopener">SIGMA subsidiary / distributor</a>.</p>
<p>We appreciate your continued support for our company and products.</p>
<span id="pty_trigger"></span>
<div style="font-size:0px;height:0px;line-height:0px;margin:0;padding:0;clear:both"></div>
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## Luds34 (Aug 9, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

Any info on liveview underexposing by like 3 or 4 stops?


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## blindcat (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

The day before yesterday I bought a 35mm 1,4 Art lens. I use it on the 5D MK IV. At home I thought first it's broken, because it showed circles and rings with sharp edges in the preview of the raws in camera (I dont store jpg). Googeling that problem brought no results! After I phoned with the store they told me to switch off all lens corrections. After that the circles and rings went away. I wish that would be clearer explained somehow. If I buy a sigma for the canon bayonett I would not be upset if at first there would be a note in the box for paying attention to lens corrections on canon cameras.
Greets,
frankie


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## weixing (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

Hi,
Did Sigma actually mention this is a bug?? Because it isn't... it work as advertised, but not with lens that "impersonate" as a Canon lens. 

By the way, I just wonder is there any Sigma lens that is compatible with Canon "Lens Aberration Correction" function? 

May be Sigma should use those lens code that Canon don't provide correction data for it, so no correction will be applied when the feature is turn on.

Have a nice day.


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## Valvebounce (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

Hi weixing. 
My understanding is that Sigma (and other 3rd party manufacturers?) use a code for a lens (not necessarily in the same focal length range?) that has similar drive requirements for the AF and IS systems so that the camera drives these systems at the desired rates? 
Using an unallocated number might result in the body identifying the lens as "no lens attached" or even worse, driving the focus system in to the end of the travel at full speed due to not having any parameters set? 
I'm not certain of any of this hence marking them as questions so that hopefully one or more of the knowledgeable members will correct or verify my understanding of the situation. 

Cheers, Graham. 



weixing said:


> Hi,
> May be Sigma should use those lens code that Canon don't provide correction data for it, so no correction will be applied when the feature is turn on.
> 
> Have a nice day.


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## weixing (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

Hi,
May be those who use third party lens affected by this issue can try removing the lens data from the camera one by one to find out which is use by that third party lens and remove them from their camera if they don't want to disable the function. When the lens data is not in the camera, no correction will be done.

Have a nice day.


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## scrup (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

Incompatibilities like this turn me off Sigma completely. You save some cash initially, in the long run it works out even if you had just gone OEM.


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## factor (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

This is not Sigmas fault - seems like Canon crippled their cameras first, and third party lenses support now...
So mutch attention to protect self pastly ... there is no other arguments more for Canon ... ?


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## privatebydesign (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



factor said:


> This is not Sigmas fault - seems like Canon crippled their cameras first, and third party lenses support now...
> So mutch attention to protect self pastly ... there is no other arguments more for Canon ... ?



Yes it is 100% Sigma's fault.

They choose not to pay for a lens registration code, that means they spoof an official Canon code, that means the camera thinks a different lens than is actually on it is on it, therefore it applies the wrong aberration corrections. How is that not Sigma's fault?

By the way Zeiss do pay Canon for unique lens codes, that is why the same thing doesn't happen to people who use native fit Zeiss glass on their Canon bodies.


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## factor (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

then ... why theese lenses are working on older Canon cameras without issues ... ?


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## privatebydesign (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



factor said:


> then ... why theese lenses are working on older Canon cameras without issues ... ?



Bescause Canon don't test for Sigma compatibility on new body firmware, Sigma do test for compatibility on older body firmware. Canon shouldn't be held responsible for Sigma spoofing lens codes.


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## Ryananthony (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



privatebydesign said:


> factor said:
> 
> 
> > then ... why theese lenses are working on older Canon cameras without issues ... ?
> ...



True. But I don't see this as being an issue anyway. As far as I'm aware, this only effects in camera jpg and it is only a problem until sigma releases a firmware update and solves the issue.


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## factor (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



privatebydesign said:


> factor said:
> 
> 
> > then ... why theese lenses are working on older Canon cameras without issues ... ?
> ...



hmmm - I realy do not think that "lens code" change self on lens, depend on what body mounted (old or new) ... ?


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## slclick (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

It's a setting, not a bug. Saying this turns you off to Sigma is a huge overreaction. Isn't it common knowledge that 3rd party glass has compatibility issues with newer bodies? Too much whining not enough understanding.


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## Mt Spokane Photography (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

All third party manufacturers have a tough time with lenses, since they must provide a code to the camera that identifies the lens. The camera firmware has a table of lenses and codes, and the capabilities and corrections for each lens. As canon expands their in-camera correction of lenses to include more models of lens, suddenly it appears that a lens is not working on the new camera. I keep the in camera corrections turned off, the corrections can be done by DPP, Lightroom, DXO, and probably most serious image editing software.

If you use third party lenses, flashes, or other accessories that electrically connect to the camera, you should expect issues until firmware fixes are issued, or you may just have a paperweight. That happened to me with Sigma lenses, 4 of 5 became paperweights because Sigma did not update the firmware. The 5th cost me $100 for the upgrade due to their poor reverse engineering. I've avoided Sigma since. Others who get caught like this are house brands which are rebadged Sigma, Tamron, or Tokina lenses. The manufacturers will not touch them, so you have to hope the original seller can fix them.


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## factor (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



Mt Spokane Photography said:


> All third party manufacturers have a tough time with lenses, since they must provide a code to the camera that identifies the lens. The camera firmware has a table of lenses and codes, and the capabilities and corrections for each lens. As canon expands their in-camera correction of lenses to include more models of lens, suddenly it appears that a lens is not working on the new camera. I keep the in camera corrections turned off, the corrections can be done by DPP, Lightroom, DXO, and probably most serious image editing software.
> 
> If you use third party lenses, flashes, or other accessories that electrically connect to the camera, you should expect issues until firmware fixes are issued, or you may just have a paperweight. That happened to me with Sigma lenses, 4 of 5 became paperweights because Sigma did not update the firmware. The 5th cost me $100 for the upgrade due to their poor reverse engineering. I've avoided Sigma since. Others who get caught like this are house brands which are rebadged Sigma, Tamron, or Tokina lenses. The manufacturers will not touch them, so you have to hope the original seller can fix them.



... thats OK - I got it ... 
I just like to highlit that corporations ( including canon) are not so friendly, like some of us can imagine maybe ...
... and are not our 'friends' ... at alll ... 
Somehow it's boring, that for all should 'pay' consumer ... isn't ?


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## gmon750 (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



factor said:


> This is not Sigmas fault - seems like Canon crippled their cameras first, and third party lenses support now...
> So mutch attention to protect self pastly ... there is no other arguments more for Canon ... ?



This conspiracy theory gets old. Stop making stuff up. Canon is not sitting around some table discussing how best to screw 3rd-party lens manufacturers. 

Canon, Nikon, and Sony are not under any obligation to keep companies like Sigma in the loop (or ask permission) when they update their cameras.

You might need a thicker tin-foil hat there buddy.


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## factor (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



gmon750 said:


> factor said:
> 
> 
> > This is not Sigmas fault - seems like Canon crippled their cameras first, and third party lenses support now...
> ...



I agree - that's not about 'conspiracy', buddy - it's about how consumers are threaded ...
anyway - I'm just trying understud myself, what kind of agreements have canon and third parties ...


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## Mt Spokane Photography (Aug 10, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



factor said:


> gmon750 said:
> 
> 
> > factor said:
> ...



Canon has stated multiple times that they do not license their lens technology to other companies. That means that the companies must reverse engineer the canon communication codes. That is not easy, as history shows. There are lens capabilities that may be unused at the present, and activated when the camera is able to make use. The new commands being sent confuse reverse engineering.

As for purposely trying to break third party lenses, there would be some very stiff fines levied in almost every country around the world if it could be proven. That does not mean they don't do it, as long as they are adding some new lens or camera capability that requires a new command to the lens or flash or whatever, they can justify breaking the 3rd party devices.


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## Romain (Aug 11, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

Firmware update needed... 5dIV has the same kind of issue at launching before the first firmware update, if i remember well... No panic mates!..


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## privatebydesign (Aug 11, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



Romain said:


> Firmware update needed... 5dIV has the same kind of issue at launching before the first firmware update, if i remember well... No panic mates!..



Yes, and the point is it is Sigma firmware update needed not a Canon one. Ergo it is a Sigma issue not a Canon one.


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## Mt Spokane Photography (Aug 11, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



Romain said:


> Firmware update needed... 5dIV has the same kind of issue at launching before the first firmware update, if i remember well... No panic mates!..



Unless a user wants to use his camera, of course. Many only own a lens or two, and if they would not work, I'd panic. Of course, there is a work around, but its been almost two weeks before Sigma admitted the issue and the work around.

Sigma erroneously misstates the release date for the 6D MK II, and the issue applies to many cameras like the 77D which was released long long ago. 

There is no mention of a firmware update, I don't think they know how.


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## Romain (Aug 11, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



privatebydesign said:



> Romain said:
> 
> 
> > Firmware update needed... 5dIV has the same kind of issue at launching before the first firmware update, if i remember well... No panic mates!..
> ...


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## rrcphoto (Aug 11, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



factor said:


> This is not Sigmas fault - seems like Canon crippled their cameras first, and third party lenses support now...
> So mutch attention to protect self pastly ... there is no other arguments more for Canon ... ?



that's rediculous. the problem is how Sigma mimics their lenses to the camera body. they give an ID number of an existing canon lens that may not even be relevant. For instance their 24-70 may be mimiced to a canon camera as being a 14mm 2.8.

at times they give an ID of lenses that are no longer supported by canon. this happened with tamron years back. caused all sorts of problems because the camera body didn't have an idea on what AF points the lens supports.

In this case, the body takes a look at the lensID number, and *assumes* it's a canon lens of a particular type - it then applies the lens aberration / vignetting correction for that lens. and lo and behold, it looks like sheit because it was actually a sigma lens instead.


care to tell me how that's canon's fault?


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## neuroanatomist (Aug 11, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



rrcphoto said:


> care to tell me how that's canon's fault?



It just is. Trust him.


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## hne (Aug 11, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



Valvebounce said:


> Hi weixing.
> My understanding is that Sigma (and other 3rd party manufacturers?) use a code for a lens (not necessarily in the same focal length range?) that has similar drive requirements for the AF and IS systems so that the camera drives these systems at the desired rates?
> Using an unallocated number might result in the body identifying the lens as "no lens attached" or even worse, driving the focus system in to the end of the travel at full speed due to not having any parameters set?
> I'm not certain of any of this hence marking them as questions so that hopefully one or more of the knowledgeable members will correct or verify my understanding of the situation.
> ...



I think you've got that wrong. If the camera had to know something about the lens so as not to drive the AF at full speed into the end (and if that was actually potentially damaging for the lens), we would be warned about having to upgrade firmware in cameras before mounting new lenses on old cameras. How many of the lenses in my signature do you think would be harmed if I mounted them to my old announced-1990 EOS 1000 (original Rebel in the US)? My guess is zero. Of all the lenses I own, only the 50/1.8 II is old enough to have been announced the same year as or earlier than the EOS 1000.

Lens aberration correction is using data stored in the body, most probably looked up by lens code. The lens codes used by Sigma/Tamron/Cosina/... are only some times values for similar Canon lenses. For example, the 35Art uses a 17-35/2.8 code and the 18-35Art uses the 85/1.2L code: https://sno.phy.queensu.ca/~phil/exiftool/TagNames/Canon.html#LensType
Modern cameras are delivered with profiles for a bizarre number of lenses. My 5DmkIV was delivered with all profiles known to the canon lens registration utility installed.

Somewhere I once found a page with detailed protocol information written by someone who had painstakingly reverse-engineered quite a bit of the EF lens protocol as a hobby project. The lens has to be surprisingly smart for a late 1980s protocol. The camera body tells the lens to refocus a number of steps in a direction and can then query the new distance (for some newer lenses, list current as of ETTL-II introduction in 2008 here: http://www.bobatkins.com/photography/eosfaq/ettl2.html )


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## LonelyBoy (Aug 11, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*



Mt Spokane Photography said:


> Romain said:
> 
> 
> > Firmware update needed... 5dIV has the same kind of issue at launching before the first firmware update, if i remember well... No panic mates!..
> ...



If you only have a lens or two, and sell your old camera before getting a new one and making sure it works for you (ideally inside the return window), my sympathy is rather low.


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## Valvebounce (Aug 12, 2017)

*Re: Sigma Warns of Lens Aberration Correction Bug with Select Sigma Lenses and Canon EOS 6D Mark II,*

Hi hne. 
Good point re the older bodies not knowing about new lenses, I guess my supposition about unused codes causing harm was wrong. 
Maybe canon know how to get their new lenses to tell older bodies what they are and what is required of the body to a level commensurate with the intellectual ability of each body, they are after all mini computers that communicate with each other! 
Maybe Σ hasn't reverse engineered that part correctly? 
On the other hand Σ don't spoof Canon lens ID's to get the lens corrections ;D, we know they don't work :, so they must spoof the ID's for some other reason leaving AF and IS parameters as the likely reasons, using unassigned ID's must have some issue or they would likely use them. Maybe the hazard with unused codes is that Canon may use that code next for a lens with completely different requirements from the Σ lens that is using it? Imagine what problems that could cause! 

Cheers, Graham. 



hne said:


> Valvebounce said:
> 
> 
> > Hi weixing.
> ...


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