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Esteemed Contributor
Posts: 3,809
Registered: ‎06-11-2013

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

I can search Google for "<brand> <model> focusing issue" (substituting various cameras in the search) and can find lots of hits of the focusing isssues for every camera I've searched for (I tried quite a few.)

 

The fact that you can find people writing about a focus problem does NOT necessarily mean that those users are using the focus system correctly.  I could not find a valid focus test (e.g. one in which the camera was stationary and an actual focus target capable of detecting front focus & back focus was used.)  I could only find hand-held snapshots for examples to validate the claim.  Perhaps something does indeed exist in which valid test conditions were used ... but in the handful of examples that I dug into, I did not come across one.

 

I did find some articles that indicated that they only seemed to be able to replicate the problem at very low focal ratios ... while doing a focus & recompose (and in fact, when I dug into other posts that were less specific, I noted that they were complaining about the center focus point and yet the out-of-focus object in the image was never actually in the center -- which further establishes that the person making the post didn't understand how to perform a test that controls the test conditions such that it would yield false results.  If you focus at f/1.4 and then recompose the frame, of course it's going to throw focus.  But that's due to the nature of very shallow depth of field and the fact that you're moving the focus plane when you recompose the camera.

 

To test focus, the camera MUST be on a tripod (no exceptions... no tripd... no valid test.  Nobody is steady enough to deal with paper thin DOF when using something like f/1.4 or f/1.2)

 

The target must be stationary.  While a focus test target is ideal (these are specially constructed to provide the contrast that the AF system needs to see AND provides a scale to determine the true focus distance -- which means you can draw more meaningful conclusions such as noticing if the camera is consistently back-focusing, etc.)  But lacking a focus test chart, you should at least be using a flat wall with a high-contrast subject ... a sheet of newsprint taped to the wall would even work.  The sensor plane on the camera must be parallel to the wall/focus-target.   The camera must not be moved after locking focus.

 

I may have been doing this long enough to know that there are people who will improperly use a piece of equipment and then blame the equipment.  There may indeed be a problem with the 70D focus system, but you'd have to test correctly to draw that conclusion. 

 

 

Tim Campbell
5D III, 5D IV, 60Da
Frequent Contributor
Posts: 34
Registered: ‎06-16-2014

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

[ Edited ]

@TCampbell wrote:

I can search Google for "<brand> <model> focusing issue" (substituting various cameras in the search) and can find lots of hits of the focusing isssues for every camera I've searched for (I tried quite a few.)

 

The fact that you can find people writing about a focus problem does NOT necessarily mean that those users are using the focus system correctly.  I could not find a valid focus test (e.g. one in which the camera was stationary and an actual focus target capable of detecting front focus & back focus was used.)  I could only find hand-held snapshots for examples to validate the claim.  Perhaps something does indeed exist in which valid test conditions were used ... but in the handful of examples that I dug into, I did not come across one.

 

I did find some articles that indicated that they only seemed to be able to replicate the problem at very low focal ratios ... while doing a focus & recompose (and in fact, when I dug into other posts that were less specific, I noted that they were complaining about the center focus point and yet the out-of-focus object in the image was never actually in the center -- which further establishes that the person making the post didn't understand how to perform a test that controls the test conditions such that it would yield false results.  If you focus at f/1.4 and then recompose the frame, of course it's going to throw focus.  But that's due to the nature of very shallow depth of field and the fact that you're moving the focus plane when you recompose the camera.

 

To test focus, the camera MUST be on a tripod (no exceptions... no tripd... no valid test.  Nobody is steady enough to deal with paper thin DOF when using something like f/1.4 or f/1.2)

 

The target must be stationary.  While a focus test target is ideal (these are specially constructed to provide the contrast that the AF system needs to see AND provides a scale to determine the true focus distance -- which means you can draw more meaningful conclusions such as noticing if the camera is consistently back-focusing, etc.)  But lacking a focus test chart, you should at least be using a flat wall with a high-contrast subject ... a sheet of newsprint taped to the wall would even work.  The sensor plane on the camera must be parallel to the wall/focus-target.   The camera must not be moved after locking focus.

 

I may have been doing this long enough to know that there are people who will improperly use a piece of equipment and then blame the equipment.  There may indeed be a problem with the 70D focus system, but you'd have to test correctly to draw that conclusion. 

 

 


The issue and how to test for it.

 

http://digital.photorecommendations.com/recs/2014/03/70d-center-focus-point-issue/

 

Also the DOF is not paper thin at 30 feet.

Esteemed Contributor
Posts: 3,809
Registered: ‎06-11-2013

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

The video that starts with "I have been shooting with my 70D for 6 months and never noticed this issue" followed by "and after I applied the AF micro-adjust the issue went away".

 

There is a reason your camera has an AF micro-adjustmment option. The camera can track the AF micro-adjust setting for each unique lens because simply changing lenses (even switching to another copy of an otherwise identical model lens) can mean you'd have to tweak it again -- that's normal and for all DSLR cameras that use separate phase detect AF points.

 

See:  http://www.lensrentals.com/blog/2008/12/this-lens-is-soft-and-other-myths

 

 

Tim Campbell
5D III, 5D IV, 60Da
Frequent Contributor
Posts: 34
Registered: ‎06-16-2014

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


@TCampbell wrote:

The video that starts with "I have been shooting with my 70D for 6 months and never noticed this issue" followed by "and after I applied the AF micro-adjust the issue went away".

 

There is a reason your camera has an AF micro-adjustmment option. The camera can track the AF micro-adjust setting for each unique lens because simply changing lenses (even switching to another copy of an otherwise identical model lens) can mean you'd have to tweak it again -- that's normal and for all DSLR cameras that use separate phase detect AF points.

 

See:  http://www.lensrentals.com/blog/2008/12/this-lens-is-soft-and-other-myths

 

 

 


 So you have no clue of the issue, you hear what you want to hear and just stay in denial there is a problem. That worked perfect with the 1Diii focus issues as well....right up until the recall.

 

Thats fine, thats what fanboys do, just own the fact and move along.

 

HE SAID.... he made mfa adjustments and it made it better but it still has inconsistant focus. So he sent it to canon repair. MFA is useless because sometimes it will front focus and other times it will back focus all in a series of ten shots. Also its next to impossible to mfa your lenses because the focus is inconsistant you never get a set number to use as a mfa baseline. After 1 test it might be +4, on the very next test it will be -3 then +12

But I am sure it wont matter just stay in denial. and all the people and all the photographers on all the forums are all just noobs who cant run the perfect 70D camera.

 

Valued Contributor
Posts: 425
Registered: ‎01-19-2014

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

@70Downer, In fairness to TC, you don't have to have your head in the sand to question whether reliability issues are genuine or not. Camera companies will always depend on customer satisfaction as a hedge against market changes and Canon is not alone in this respect. My point is, your concerns may in fact be considerable, a fix may be in the works, and try to chill - this isn't "class action" sort of material. At least, not IMHO.

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

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


@cale_kat wrote:

@70Downer, In fairness to TC, you don't have to have your head in the sand to question whether reliability issues are genuine or not. Camera companies will always depend on customer satisfaction as a hedge against market changes and Canon is not alone in this respect. My point is, your concerns may in fact be considerable, a fix may be in the works, and try to chill - this isn't "class action" sort of material. At least, not IMHO.


Nobody said anything about class action suits or anything else. just when is canon going to fix a KNOWN problem with many 70D's. Its a valid question, especially if you have one of the bad ones.

Only to be greated by obvious fanboys who live in a bubble where all canon cameras are great and any known issue is a user error.

He is the same type that hollered all the same things about people who were having problems with their 1D iii's. It took 2 years of constant canon (and their fanboys) denial before a second recall and most of them who still owned the camera got a fix. Many just sold the POS at a loss

The 70D appears to be going down the same exact path.

Esteemed Contributor
Posts: 3,809
Registered: ‎06-11-2013

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

[ Edited ]

So... wanting a valid test with controlled conditions to isolate a "problem" (a problem... I should point out, that in the last two videos I watched seems to be so difficult to detect that the people who made the videos claimed to have never even noticed at all.) makes someone a fanboy??

 

This is sort of like the people who screamed about the iPhone camera "well... if I point the camera DIRECTLY AT THE SUN ... then I notice this extremely slight purple fringe around the corner of the frame".  <sigh>

 

You seem a bit paranoid as if we're all against you.  Expecting a valid test before we all start pounding on Canon is hardly grounds for dismissing someone as a fanboy.

 

If you knew me, you would hardly consider me to be a "fanboy".  But what I am is a very science-minded person and I expect you to bring solid evidence to back up claims.  Go do your homework.... DO YOUR OWN HOMEWORK and stop watching YouTube videos. 

 

There may well be a problem with the focus system on the 70D.  But currently there doesn't seem to be a rash of people who can actually notice this issue all on their own... just a tiny population of people using FUD (fear uncertainty doubt) to scare people into a panic.  Get me some evidence (real evidence) and I'll be on your side -- better yet... Canon might actually be on your side.

 

 

Tim Campbell
5D III, 5D IV, 60Da
Frequent Contributor
Posts: 34
Registered: ‎06-16-2014

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

There are many valid test out their. I am not going to go dig them up and try to convience you of anything. I really dont care if you believe me or any other person. You can stay in your fanboy world forever. I dont care if you are on any side.

But take your fanboy denial and go to a different thread if you have nothing to offer to the people who asked a ligitimate question. Other then you aren't satisfired there is a problem, do you really think of yourself that highly rated that people on a forum must meet your conditions?

There is a problem, many people have the same exact problem and yes its pretty limited in that you must have a fast lens and shot at longer ranges with it and of all things expect your 1200 dollar camera to get focus. At least at a better rate then a t3i. It leaves out many of the people who just use the kit lens and many dont know their camera will focus badly at 1.4. They just think it was operator error. Until you put it on a tripod and start testing it to try and figure out why your t3i with no mfa or high tech focus system can out perform your new camera with the same lenses.

 

I really dont think anybody is against me, not even you. Cale mentioned a class action suit which i never said and agree with. This is nowhere near class action suit material.

You, I am sure you are the same type that thought all the 1D iii's focus issues were a small section people who couldn't use their new camera's. And there is nothing wrong with that, the world needs fanboys too.

Valued Contributor
Posts: 425
Registered: ‎01-19-2014

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

Last call.Smiley Very Happy

 

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

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

@TCampbell
In my case, it's been very complicated to isolate the issue with test pictures (but I'm working on it). Because it looks like the wide black and white test targets are too easy for the sensor, the camera seems able to see that it is out of focus. But as soon as you do some subject photography, on less contrasted elements, it's completely out of focus.

The only measurement I could reliably make (with several lenses) was mapping the AF area.
Look at that post :
http://forums.usa.canon.com/t5/EOS/EOS-70D-focus-issue-question/m-p/97566#U97566

And answer my question : is it normal to have something so misaligned ? I haven't got a 7D or a second 70D to compare, so I have no clue.

More importantly, can Canon technicians fix that issue ? Because on the service manuals I found, I didn't see any procedure for AF sensor mechanical alignment. It looks like Canon just screws on the AF sensor and then does a software calibration wishing the manufacturing tolerances to be within specs. For the moment, my best explanation would be that if the sensor is too far or too close from it's ideal position, it might be trying to focus on a blurred signal, and it can only see extremely wide and well contrasted subjects.

Look at the pictures in these post, and tell me if that's how a camera's AF is supposed to work :
http://photography-on-the.net/forum/showpost.php?p=16974971&postcount=832

http://photography-on-the.net/forum/showpost.php?p=16969299&postcount=814
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