Canon 70d center focus point -bug- problem

[wickidwombat]

Have gone through the POTN thread and some people there are even implying that people "without" this problem do not know how to use their cameras. So, I guess the people posting excellent shots on the 70d sample thread don't know how to use their 70ds.

Ah - the dreaded "Dunning-Kruger Effect":

"The skills needed to produce logically sound arguments, for instance, are the same skills that are necessary to recognize when a logically sound argument has been made. Thus, if people lack the skills to produce correct answers, they are also cursed with an inability to know when their answers, or anyone else's, are right or wrong. They cannot recognize their responses as mistaken, or other people's responses as superior to their own."


"The Dunning-Kruger effect occurs where people fail to adequately assess their level of competence — or specifically, their incompetence — at a task.

This lack of awareness is attributed to their lower level of competence robbing them of the ability to critically analyse their performance, leading to a significant overestimate of themselves. Put more crudely, they're too stupid to realize they're stupid."

LOL I like this post alot

 

[unadog]

LOL I like this post alot

I suppose it is a bit mean, at least that last line is.

But the only ones who should take offense to that are the ones who insist that "if you don't have a problem, you don't know how to use your camera."

Just another internet conspiracy theory. Lots of talk in those threads about how widespread the problem is, how "1 in 1,000 defects is too many", how Canon is hiding it the problem, etc.

People just need to educate themselves.

Cheers!

 

[unadog]

This issue really says one thing: DPAF rocks! Some of the videos out there are pixel peeping at 200% to notice the difference. This is not a new issue, but since live view focusing is suddenly super accurate people start to realize that phase detection AF has acceptable tolerances. That is why AFMA was created.

This is a great summary!

Luds34's post was also spot on.

I don't mean to be mean to anyone, but this is very sophisticated equipment in many ways. What people are describing as a defect is 1.) Present on every camera made, and 2.) User error ...

Cheers!

 

[Logan]

Last time I checked, germany runs on 50hz power, and sometimes 41?

Either that or a popular german youtube video causing "wind power syndrome" are my guesses as to why the conspiracy exists mainly in germany.

 

[Don Haines]

Last time I checked, germany runs on 50hz power, and sometimes 41?

Either that or a popular german youtube video causing "wind power syndrome" are my guesses as to why the conspiracy exists mainly in germany.

Great Britain also runs of 50Hz and the problem has not been reported there.... but then again, it could be that because Brittan is so foggy that nobody can tell if the image is out of focus.....

 

[Mt Spokane Photography]

check this out for a bit more detail.

http://photography-on-the.net/forum/showthread.php?t=1354075


Not all the people reporting issues are as poor at photography as your comments suggest.

The issue is sorting out the experts, from those who do not have a clue.

There are plenty of web sites that do competent testing of products, and a few that don't. However, there are tons of people having issues with equipment who have not determined what the cause of the issue might be. Competent sites test known good lenses, and if one fails, they test three more. Since the Canon 50mm f/1.8, for example, is well known to be inconsistent in autofocusing (There is a lot of carefully done testing on this), any test using a lens like that is suspect, because of the issue that they are using a lens that is almost certainly the issue.

If you want to leave CR because experienced people are telling you something you don't want to hear, you can delete your own account, you do not need to ask a administrator.

I'd suggest that you take advantage of advice from the many good photographers on this site, and go to some of the premiere test sites and read actual test reports rather than taking posters in forums at face value. Many forums have some really good photographers, but the test sites tend to be a cut above because they have expensive software and the knowhow to avoid the pitfalls that do it your self experts step into. Some of those experts post on multiple sites, and others pick those posts up and repost links to them, and pretty soon, there are hundreds of reports that are really started by the single clueless individual.

Here are some of the well known sites that are fairly competent, and do testing on equipment that was not supplied by the manufacturer. Photography on the Net does not buy and test equipment or issue test reports. I don't bother to read their forums, there are probably some good and accurate reports among the many bad ones, its always that way. We always get a laugh when someone reports a finding by Ken Rockwell, so don't use him as a expert.

The Digital Picture

Photozone

Digital Photography Review

Lens Rentals. They have some of the most sophisticated gear of any test site, and know how to use it. They also test many copies of the same brand and model of gear, so they know when one is different from the other X hundred they tested.

Luminous Landscape (Gets Sony cameras to review from a dealer, sometimes Sony as well). They do not pull punches if a Sony camera has a issue.

Lens Tip is competent, but they get equipment loaned by manufacturers, so that always casts some doubt as to whether the equipment was hand picked for testing.

 

[jarrieta]

Have gone through the POTN thread and some people there are even implying that people "without" this problem do not know how to use their cameras. So, I guess the people posting excellent shots on the 70d sample thread don't know how to use their 70ds.

Ah - the dreaded "Dunning-Kruger Effect":

"The skills needed to produce logically sound arguments, for instance, are the same skills that are necessary to recognize when a logically sound argument has been made. Thus, if people lack the skills to produce correct answers, they are also cursed with an inability to know when their answers, or anyone else's, are right or wrong. They cannot recognize their responses as mistaken, or other people's responses as superior to their own."


"The Dunning-Kruger effect occurs where people fail to adequately assess their level of competence — or specifically, their incompetence — at a task.

This lack of awareness is attributed to their lower level of competence robbing them of the ability to critically analyse their performance, leading to a significant overestimate of themselves. Put more crudely, they're too stupid to realize they're stupid."

LOL! Nice.

 

[Lightmaster]

well the 70D seems to have a center focus point bug with some lenses.

that´s why some people are unable to get sharp images, for example, with a 24mm f1.4 and the center AF point on a 70D.

you can´t do much wrong when your camera is on a stative and you test the same setup with a 60D and it works.

http://www.canonrumors.com/forum/index.php?topic=19673.msg380127#msg380127

there are a lot of people who complain about this.. no need to add insult to injury and claim they are all idiots.

 

[Lightmaster]

Last time I checked, germany runs on 50hz power, and sometimes 41?

Either that or a popular german youtube video causing "wind power syndrome" are my guesses as to why the conspiracy exists mainly in germany.

in fact i just checked the two main german forums i visit and yes.. i count at least 80 different people claiming to have this problem. then i stopped counting.

Some of those experts post on multiple sites, and others pick those posts up and repost links to them, and pretty soon, there are hundreds of reports that are really started by the single clueless individual.

saying they are all the same individual is a bold claim .. but you are mr. knowitall so i guess you must know. :

they guy in the youtube video i have posted month ago is maybe not a good artist.
but he wrote countless books about canon cameras... so he knows the settings.
im not a fan of his website but in this case i don´t see what he has done wrong and why the 60D works fine in his hands but the 70D not.

especially as i watched my friend doing a similiar test with the same result.

Lens Rentals. They have some of the most sophisticated gear of any test site, and know how to use it. They also test many copies of the same brand and model of gear, so they know when one is different from the other X hundred they tested.

and they test every camera model with every canon lens model in center AF focusing mode?
you know your reply is nonsense?

some 70D owners say their 50D or 60D work flawless with certain lenses... but the 70D not.
i have no reason to call them all liars.

please explain how these people are "experts" and good photographers when they use the 50D/60D but suddenly become clueless noobs when they use the 70D.

I'd suggest that you take advantage of advice from the many good photographers on this site, and go to some of the premiere test sites and read actual test reports rather than taking posters in forums at face value.

but only as longs as it fits your own opinion i guess.
DXO is not well received under canon users... all their equipment and know-how suprisingly does not change that. :

 

[Lightmaster]

I also why "30-50 percent of cameras in Germany" have this problem....

Hysteria!!


The second video should have taken this on much more strongly. This is just nonsense,

1. YOU CANNOT HAND HOLD AN 85 1.2 or 50 1.4 and hit your focus target consistently wide open!

2. YOU CANNOT FOCUS AND RECOMPOSE wide open! The camera needs to be locked down on a tripod for these tests.

3. You have to learn A LOT about autofocus to understand how to accurately test your focus.

all done in other tests.. same result: 70D does not focus correctly... 60D does.

4. You have to learn A LOT about autofocus to understand the different features/settings on auto focus.

so why not enlighten the noobs who have this problem?
why is it so much harder to focus with the 70D and certain lenses in AF center point mode... compared to, for example, the 60D or 50D?

i don´t have the 70D but a friend showed me the issues with his 24mm f1.4... i saw no fault in his test setup.

tripod, fixed target, same light conditions. what can an AF system ask for more?
60D was able to find the point of sharpest focus every time.
the 70D not, but with contrast AF the 70D was fine.

 

[PicaPica]

[quote author=Mt Spokane Photography]

There are plenty of web sites that do competent testing of products, and a few that don't.

I'd suggest that you take advantage of advice from the many good photographers on this site, and go to some of the premiere test sites and read actual test reports rather than taking posters in forums at face value. Many forums have some really good photographers, but the test sites tend to be a cut above because they have expensive software and the knowhow to avoid the pitfalls that do it your self experts step into.
[/quote]

When was the last time one of the websites you mention have found a bug in one of the products they have tested? Found! Not just reported.

The light leak bug in the 5D MK3.
Not a bug some say.. yet canon has fixed it.

The "white rubber" issue.

Tons of other examples where the "Bugfinder" are ordinary people in photography forums.

A testchart and other testgear will not help you find issues outside their line of use.
Review sites are usually in a hurry to get their reviews out. Longtime tests.. who does them, beside Lensrentals?

Don´t be naive. No review websites can test everything.
It is the same as with car magazines.
If you would believe them no car ever would need a recall.

 

[PicaPica]

Here are links about this:

Well, the first video is a useless joke. Evidence? I see none. Zero information about the lens used, the camera settings, or the set up. The most obvious answer to that "problem" is that the lens needs AFMA – sharper with live view than with phase AF is the easiest test to determine that. I chuckled at the claim that "a good knowledge of photography" is necessary to detect the problem. That's what we call irony. :

The second video says exactly what I just said – the focus was off with the 50/1.4 at f/1.4, and AFMA corrected the problem. Duh. He then goes on to suggest there is, in fact, a problem with some cameras – but he has no evidence for that, except "some people on the Internet say"…

Were these two videos the best 'evidence' you could come up with? I think the only problems you're seeing are wetware errors – the person holding the camera is the issue.

I guess you have not read the discussions about it?
No amount of AFMA will fix the problem.

As it was stated by Lightmaster.. that does not explain why other Canon Bodys work fine with the same lens type.

His argument that advanced Photographers do not suddenly become newbies when they use a 70D makes sense.

 

[Loswr]

60D was able to find the point of sharpest focus every time.
the 70D not, but with contrast AF the 70D was fine.

I have several lenses which needed 10 units or more different AFMA settings on different bodies – over a full depth of focus off. So it's easily possible that a 60D could focus correctly and a 70D could be way off with the same lens.

In the case where the center AF point consistently misses focus, but an immediately adjacent AF point consistently achieves correct focus (assuming equivalent directional contrast for both points), that pretty clearly indicates a hardware or firmware defect. So far, I've seen one – just one – example of that.

There's also confirmation bias...one person with a defective camera posts information about it (perhaps in German on a German forum?), and suddenly many people 'find' the same problem (if they read German?), except their cameras are fine, it's their testing that's defective.

Tons of other examples where the "Bugfinder" are ordinary people in photography forums.

Canon doesn't care about 'bug reports' on Internet forums. Anyone who thinks their camera is defective should send it to Canon. It seems that several people have done so, and been told that their camera is within spec. A Canon 'coverup'? No, you can put away the conspiracy theories. The simple answer is their cameras weren't defective.

When there's an issue, Canon fixes it. If a hardware issue is widespread, Canon issues a Product Advisory; firmware issues are fixed with a firmware update.

 

[Don Haines]

It's the claim of 35-50 percent of people in Germany have this problem that gets me....

The logic is flawed. If the problem is so widespread in Germany, it must be the same elsewhere, so why is it not showing up elsewhere in those numbers?

 

[dadgummit]

I don't know if there is a bug or not but I just purchased a new 70D from B&H last week and the center focus point works perfectly with the 85mm f1.2 and other faster than f2.8 lenses.

Personally I am willing to bet that there are a few defective cameras out there with some kind of issue and when other people start pixel peeping their fast lenses at long distances the are surprized that the camera has issues getting a sharp f1.4 shot at 20 feet out. So they think they have the issue too.

Whenever I shoot a wedding with low light I have the cameras in High speed continuous all the time. Out of 4 shots of the bride eating her cake maybe 2 are in perfect focus. The ironic thing is that she will often choose one of the less perfect shiots for her 8x10 and guess what it, comes out great! Pixel Peeping has made the lives of Canon's engineers in the af department very difficult.

 

[unadog]

What we need to see to know if there really is a problem is an autofocus test similar to those done by Roger Cicala.

Every auto focus system will deliver a range of values. Look at how he measured the accuracy of focus on different bodies and different lenses.

He did 10 repeated focus attempts with phase detection and manual focus. Gave us the standard deviation of the focus error.

Compared that between older Canon bodies and newer Canon bodies. And also found out that newer lenses focused more accurately.

So you need to repeat the focus test 10 times, because it will vary. Measure those errors. Use one of the newer Canon lenses. And compare that to cameras of the same class - 60D, 50D, T4i.

SHOW US THE STATISTICALICAL ANALYSIS. ACCOUNT FOR KNOWN VARIATION IN PERFORMANCE.

Show that you understand the system well enough to demonstrate an anomoly.

Most of this is just people finally learning how auto focus works.

Please, read these articles. Then we can talk:

Roger Cicala's posts on auto focus:

Autofocus Reality Part 1

http://www.lensrentals.com/blog/2012/07/autofocus-reality-part-1-center-point-single-shot-accuracy

http://www.lensrentals.com/blog/2012/07/autofocus-reality-part-ii-1-vs-2-and-old-vs-new

http://www.lensrentals.com/blog/2012/08/autofocus-reality-part-3b-canon-ca


Roger Cicala: "Why You Can't Optically Test Your Lens With Autofocus"

http://www.lensrentals.com/blog/2014/02/why-you-cant-optically-test-your-lens-with-autofocus

 

[unadog]

Roger Cicala: "Why You Can't Optically Test Your Lens With Autofocus"

http://www.lensrentals.com/blog/2014/02/why-you-cant-optically-test-your-lens-with-autofocus

To summarize my point, if I am checking a lens like our techs do all day, manual focus is simply much more accurate than phase-detection autofocus.

 

[unadog]

More text from that article:

"Let me again differentiate ‘testing quality focus’ from ‘picture taking focus’.

If I was taking a 3-Dimensional picture, all of the images above the 850 line would be virtually indistinguishable. The two phase-detection shots that are lower would probably be acceptable; if you were comparing identical shots you might notice the two had slightly missed focus, but not horribly.

But when we’re assessing a 2-dimensional test chart, that would be enough to make the lens look unacceptable.

Phase detection accuracy is different with different cameras and even with different lenses on the same camera. The pair used in this example are quite accurate; not the very best, but better than average. The very best (in these conditions) we’ve tested, the Canon 5DIII or 1Dx with certain lenses, are nearly as accurate as contrast detection AF.


Good microfocus adjustment lets the phase detection system focus at the proper location, but it can’t make the pattern of variation much smaller. (If MF adjustment is really off, the pattern can be bigger than this, but this is about as good as it gets.)

One other point that will become more apparent with the next two posts: some of the most sensitive indicators of a decentered lens are seen when it’s just barely out of focus. So the testing I’m going to describe will require evaluating the lens both in focus, and just barely out of focus in both directions. You can’t do that kind of evaluation with phase-detection AF.

So What’s Next?

This first post was to demonstrate that hand-held, autofocus optical testing isn’t very useful. If you want to test a lens using autofocus go take pictures and see if you like the lens, which is really what I recommend everyone do, anyway.

 

[unadog]

OLD Lens Versus NEW Lens



http://www.lensrentals.com/blog/2012/07/autofocus-reality-part-ii-1-vs-2-and-old-vs-new

The OLD Canon 24mm f/2.8 lens was released in 1988 making it one of the oldest designed Canon lenses available.

while the NEW Canon 24mm f/2.8 IS USM was just released last year.


GRAPHS IN ORDER:

1.) The OLD 24 mm on an OLD 5D Mk2

2.) The OLD 24 2.8 on a NEW 5D M3

3.) The NEW 24 2.8 IS on a NEW 5D M3


Look at that last graph! Newer lenses are amazingly good on a newer body.

 

[David_in_Seattle]

I rented a 70D right when it was released to compare it to my aging 60D for both photos and videos (primarily for video). I never encountered a problem using the center AF point with a fast prime (50mm f1.2, 85mm f1.2, Sigma 18-35 f1.8 ) under normal lighting conditions. Note: all cameras will have problems focusing on low contrast subjects or in poor lighting conditions; for that I recommend attaching a Canon speedlite.

When using the live view the AF phase detection system is very useful, though it also has problems focusing on low contrast subjects. I've used it to record a break dancing competition under terrible lighting conditions while using the Canon 17-55 f2.8 IS. Overall, focusing was hardly a problem whereas most of my concern was recording at ISO 3200.

Ultimately I recently decided to buy a 70D to replace my 60D. I prefer using the 70D for run and gun video recording compared to my 5Dmk3 and 1Dx because it's lighter and has a useful live view AF system.