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Frequent Contributor
Posts: 42
Registered: ‎06-17-2014

Re: When will canon fix the focus issues with the 70D?

[ Edited ]

@70Downer wrote:

That does abosultely nothing to help any of the people with the broken 70D's does it Keithr?  Or when canon will have a fix out for all of the broken 70D's. Good thing you chimed into a thread labeled when will canon fix the 70D with "yours is excellent"

 

What great input, thanks.  SMH


Let's be clear about a few things.

 

In terms of challenging Photogirl's assertion that the internet is aflame with complaints that the 70D can't AF - in other words, in terms of suggesting that keeping a realistic sense of perspective would probably be a good idea - my comments are very helpful indeed.

 

But they weren't intended to help you, because you've given us precisely nothing on which to base helpful suggestions, and you've done nothing to prove your case except point at other people's supposed problems, and to charcterise anyone who has the temerity to take a slightly different view to yours, as a fanboy.

 

Where's your proof? How do we know that you haven't got your 70D set up badly?

 

And don't assume that you know everything about how to use your camera: it's not that long ago that I helped my shooting partner - an ex pro - with his 7D's AF "problems", by getting him out of AI Focus... 

 

So how do we know that for whatever you shoot (and for clarity, I use my 70D for birds and fast motor sport - an AF challenge if ever there was one) you haven't got entirely the wrong AF menu options selected?

 

In other words, where's the evidence that you've definitively ruled yourself out as the problem?

 

Do that, and maybe there'll some basis for progress. But don't expect to win any moral high ground with your "I'm shouting loudest so that must be enough proof..." line of thinking. We've seen it all before, and righteous indignation is no substitute for evidence.

Frequent Contributor
Posts: 42
Registered: ‎06-17-2014

Re: When will canon fix the focus issues with the 70D?


@70Downer wrote:

Also the DOF is not paper thin at 30 feet.


It's thin enough: just yesterday I was shooting a bird at about that distance at f/2.8: I'd focused on its "shoulder" rather than on its eye, and at that distance, the "missed" focus was enough to give me a picture of a sharp body and OOF head.

Frequent Contributor
Posts: 42
Registered: ‎06-17-2014

Re: When will canon fix the focus issues with the 70D?


@Molybdo42 wrote:
Look at the pictures in these post, and tell me if that's how a camera's AF is supposed to work

Well, obviously not.

 

But in both of those shots, what has happened could have happened with any camera: in the first one, the AF point has overlapped the subject and - because there was more behind him for the AF to grab onto - has focused on the backgound clutter; and on the second one, it's just out of focus, which sometimes just happens - although given that the grass around the same plane of focus as the intended AF point is sharp, I'd put this one down to a thin DoF.   

 

Point being, neither of these behaviours is unique to the 70D, and in that very thread, for pretty much every "definitive" claim made by Scoobert, there are well-argued rebuttals.

 

As it happens, he might well have a squirrely camera (it happens), but the idea that the 70d is inherently flawed is just - to be blunt - ridiculous: believe me, I'd be at the front of the queue with proof, if that was indeed the case.

 

More to the point, I can post umpteen "proofs" that the 70D per se isn't "flawed" - but for some reason there's always this "selective reading" in these situations, where only the online evidence that "proves the probem" is ever cited.

 

Confirmation bias.

 

Funny, that..

 

Oh - and for completeness, "Mike55", one of the complainants on that thread admits he's using One Shot AF for his OOF bird shots!

 

Wrong AF mode! 

 
Frequent Contributor
Posts: 44
Registered: ‎06-08-2014

Re: When will canon fix the focus issues with the 70D?

[ Edited ]

@ KeithR,

I can understand that you can be sceptical about focus issues on a dslr because indeed the cause is often behind the camera !

 

I know that some people have 70D with no issues, and you seem to be one of the lucky ones.

 

I'll go further and say that I'm almost convinced that the 70D issue doesn't come from a design error but from some in factory calibration or some camera components not being to spec. I'm talking about tens of microns here !

 

For example, I bought a focus screen with split prism on ebay for my 500D. Unfortunately, the prism was a little too thick and gave me some serious back focus issues in manual focus through the viewfinder. I solved that issue with a trick used in optics : simple 3M masking tape has thickness of rougthly 50µm, so, to adjust the total tickness, I "simply" had to use several layers of tape on the side of my focus screen until I could get the desired focus. So imagin, in the case of the focus screen, the distance has to be +-50µm from the ideal position to give correct focus ! That's the thickness of a hair !

 

WIth a margin for error so small, it's easy to understand that the AF sensor can be misaligned on several 70D. The origin could be that Canon has a problem with one of his calibration equipment or methodology, that's the fun part because this can result in a wide batch of defective cameras...

 

 

Now since the "give me proof" argument works both ways, I really want to know if my AF zones are normal, and if in my case the focus issues can come from a misalignment of the AF sensor. But up until now no one did the same test as me. Also for some reason, no one answered all my questions, do I need to rephrase them ?

 

 

Since you kindly proposed it could you please provide me some test pictures to map the AF points in your camera ? No need to assemble the images by yourself, put the pictures somewhere where I can download them. You can send them in low res jpeg (keep the raw files in case), I will merge them and post the results here.

 

 

Here's the testing procedure :

You'll need a computer screen, a mirror, the image file below with the black rectangle, a tripod, and if possible a remote.

It should take you one to two hours to map the 19 focus points (76 pictures) ; but for a quick assessment, I think you can limit yourself to the nine focus points located at the center. The goal is to move the black and white edge ntil the camera is barely able to focus.

http://i1262.photobucket.com/albums/ii604/Molybdo42/AF_areaTest-01_zps4366f833.png

 

Setup procedure :

  • Set the camera to manual mode single point focus, lens in autofocus mode
  • Set the file size to record full size raw and 5 megapixels JPEGs (S1)
  • Put the camera on a tripod
  • Open the picture with windows viewer, and zoom in until you can move the black rectangle across the entire screen
  • Quickly adjust the camera height position distance until you see nothing else except the black rectangle on white background,
  • Put the mirror flat against the lcd (you can use some 3M paper tape, the white one ; careful not to damage your screen)
  • Adjust the camera height, position, tip, and tilt ; until the image of the lens (visible in the mirror) is aligned with the center of the LCD (use LiveView). Tighten the tripod and check that the camera hasn't moved.
  • Remove the mirror

 

For each focus point :

  • With your mouse, while pressing several times the "AF-on" button (don't forget to configure the button to do auto focus) move the black rectangle towards the exterior of the focus mark until the focus can no longer be achieved (lens hunting)
  • Move back the rectangle a tiny bit until you can lock focus (use the green dot in the viewfinder to confirm the focus)
  • Take one picture, do the same for all four sides of the focus mark (you will see the focus area extends quite a bit
  • Repeat steps for all focus points

 

Important : for me, in order to analyze the pictures, the file numbering is important, so for each focus point take four (only four) consecutive pictures, don't mix them.

 

Frequent Contributor
Posts: 34
Registered: ‎06-16-2014

Re: When will canon fix the focus issues with the 70D?

Hopefully somebody with a 70D or maybe even canon techs can help you Molybdo42.  Mine is on its way to canon virginia for this focus issue now or I would try to do what you want.

 

Also would like to appologies to TCampbell for calling him names while he was trying to do nothing but help.

Sorry sir.

Highlighted
Occasional Contributor
Posts: 5
Registered: ‎07-14-2014

Re: When will canon fix the focus issues with the 70D?

Molybdo is the first person who's suggested an actual test that benefits anyone who thinks they have a focus issue... MAJOR KUDOS. You know as a new photographer, I find it interesting that the "old pros" (who obviously must be old because of how much of a curmudgeon they are) chim in on these things, all they do is rip on people and insult them. Heck, that's what I view as what's wrong witht he photography industry as a whole. Why would I even enter, when the public's perception is that "we" are all jerks? LOL

 

If "this kind of thing" is SOOO common, you "old pros", why don't you have a copy & paste doc readily available with suggested tests that the various people could use for help, rather than just being negative to everyone... 

 

There's a right way to say things, and there's a wrong way to say things... Try to use a little tact or simply don't respond. You're not doing people much good in the way you seem to be doing things right now. 

 

Frequent Contributor
Posts: 44
Registered: ‎06-08-2014

Re: When will canon fix the focus issues with the 70D?

@ ghstinshll Thanks !

But I still don't know if this method works or not, no one (with a working or faulty camera) did the same measurements.

 

The only other test that I could think of would be to use Reikan Focal to measure the micro focus adjust values for all focus points. This allowed many users with faulty Nikon D800 to check their AF system :

http://www.falklumo.com/lumolabs/articles/D800Focus/SensorArray.html

 

Another step by step can be found here :

http://www.bythom.com/autofocus.htm

 

Now troubleshooting whether or not the AF sensor is misaligned is difficult without any equipment and it might need taking appart the camera (things that I don't want to do, so I sent mine for repair). For the moment my best guess would be that my camera's AF sensor is almost parallel to the imaging sensor, but too far or too close from it's ideal position. That would mean that the phase detect would try to work with a blurred signal, losing all details. For the moment that would explain why I can focus reliably on wide black and white focus targets (typically the kind of thing used when doing micro focus adjust), but not on sujects with lots of small details.

 

I found a description of the AF repair procedure for Nikon :

http://hifivoice.wordpress.com/2012/07/14/d800-autofocus-repair-overview/

In Canon's case, no idea...

 

Also, I don't know if camera manufacturers also calibrate the position of the AF sensitive areas and then disable unused pixels on the AF sensor strips (that would be evil...). I certainly know that this would be feasible because the 7D (not the 70D) has a spot AF mode.

Respected Contributor
Posts: 1,861
Registered: ‎12-02-2012

Re: When will canon fix the focus issues with the 70D?

[ Edited ]
I feel bad for anyone with a frustrating camera problem, whether it is a widespread design flaw for the whole product, a rare bad unit, or simply user error.
I will say I find the backlash sort of funny though. On Canon forums (not just this official one) you see the True Believers savaging anyone who thinks there could be a defect in Canon equipment/firmware/ etc.. They get so defensive it sometimes gets a little ugly.
And YET you will see the same ones claiming that there is an incurable inherent fatal flaw in third party lenses (like Sigma) and hotly denying that it could be an isolated bad unit or, gasp, user error.
Just amusing is all.
Scott

Canon 5d mk 4, Canon 6D, EF 70-200mm L f/2.8 IS mk2; EF 16-35 f/2.8 L mk. III; Sigma 35mm f/1.4 "Art" EF 100mm f/2.8L Macro; EF 85mm f/1.8; EF 1.4x extender mk. 3; EF 24-105 f/4 L; EF-S 17-55mm f/2.8 IS; 3x Phottix Mitros+ speedlites

Why do so many people say "FER-tographer"? Do they take "fertographs"?
Valued Contributor
Posts: 425
Registered: ‎01-19-2014

Re: When will canon fix the focus issues with the 70D?


@ScottyP wrote:
I feel bad for anyone with a frustrating camera problem, whether it is a widespread design flaw for the whole product, a rare bad unit, or simply user error.
I will say I find the backlash sort of funny though. On Canon forums (not just this official one) you see the True Believers savaging anyone who thinks there could be a defect in Canon equipment/firmware/ etc.. They get so defensive it sometimes gets a little ugly.
And YET you will see the same ones claiming that there is an incurable inherent fatal flaw in third party lenses (like Sigma) and hotly denying that it could be an isolated bad unit or, gasp, user error.
Just amusing is all.

Oh yeah? So... how do we rate?

Frequent Contributor
Posts: 42
Registered: ‎06-17-2014

Re: When will canon fix the focus issues with the 70D?

[ Edited ]

@ScottyP wrote:
 you see the True Believers savaging anyone who thinks there could be a defect in Canon equipment/firmware/ etc.. 

There's been no "savaging" here - although the infantile reaction to the reasonable expectation that the "victims" demonstrably rule themselves out as "The Problem" is predicatble enough.

 

It's not defensive to expect this, and utterly unfair to characterise it as such: it's a fundamental part of trouble-shooting, and all your post does, Scotty, is to act as provocation to both of these supposed sides: there are no sides here - everyone posting wants to get to the bottom of this. Some of us just want to see the job done properly.

 

And that's because it's clear beyond any doubt that there's no "focus issues with the 70D", as the title of the thread asserts.

 

There will certainly be some faulty individual bodies, but that's not the same thing by any stretch of the imagination: and anyone who tries to stretch the occcasional faulty camera into proof of inherent failure in design/manufacture is - well, to be kind - not very bright, and they're also ignoring history - I've seen exactly the same nonsense from the 30D onwards.

 

Some of us have been doing this long enough to know the difference - which fact is apparently enough in itself to provoke condemnation from some contributors, like @ghstinshll - but it's a foolish thing indeed to ignore that experience in favour of cheap shots which help nobody and which move the discussion backwards, especially given threads like this one: 

 

http://forums.usa.canon.com/t5/EOS/70D-Image-Quality-Worse-than-T3i/td-p/104094 

 

which makes my case for me better than I ever could myself. User error, pure and simple - as most of these "problems" will surely be. 

 

Like I say: you ignore experience at your peril. None of this is new.

 

There's nothing fanboyish in taking this view (God knows, there are plently of things to berate Canon for - I'm still waiting for a camera with same Auto ISO capabilities that I had in my Nikon D70 way back in 2005) but - once more for the avoidance of any doubt - some faulty cameras (and a lot of poorly-used ones) does not equal across-the-board "focus issues with the 70D".

.  

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