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7D focus issue help

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Zee Char said:
The EXIF shows that shot was taken in AI-Servo.
Click to expand...
Thanks Zee! How did you view the EXIF?

OP ..

Do not shoot your LensAlign target in AI-Servo!

Please use One-Shot AF when testing and when MFA'ing.

Redo your MFA in One-Shot, then retest and let us know how you go.

It's not a problem - you probably didn't know or were misled. No big deal. But it really is important to use One-Shot for your MFA'ing. :-)

Hopefully we'll get a bit closer to getting your 7D working as it should! :-)
 
schmegg said:
Zee Char said:
The EXIF shows that shot was taken in AI-Servo.
Click to expand...
Thanks Zee! How did you view the EXIF?

OP ..

Do not shoot your LensAlign target in AI-Servo!

Please use One-Shot AF when testing and when MFA'ing.

Redo your MFA in One-Shot, then retest and let us know how you go.

It's not a problem - you probably didn't know or were misled. No big deal. But it really is important to use One-Shot for your MFA'ing. :-)

Hopefully we'll get a bit closer to getting your 7D working as it should! :-)
Click to expand...
OP did a screen shot on the third post. Also take the IS off when doing MFA.

--

Weaseling out of things is important to learn! It's what separates us from the animals. Except the weasel.

Homer Simpson
 
Hi all,

Thank you very much for all of the responses.

The first picture I posted (of the boy) was using AI-Servo.

The second LensAlign pictures were done in Single shot focus mode. The difference in AF functionality is what bothers me the most about these photos. FWIW I also tested using Live Mode AF and every image was spot on.

I have MA'd all of my lenses and both groups of pictures were done with my MA settings turned on (+5 in this case).

Some people mentioned that you should never use AI-Servo with static subjects. I thought AI-Servo with back-button focus was similar to Single shot because you can simply let go of the button to lock focus. Is this not suggested?

I will report back once I have some natural light shots. I will post them with full EXIF.

Thanks again!
 
Maybe it was just me, but when I tried to MFA my lenses using the Spyder LensCal target I was misjudging the amount of change needed, even with all the techniques mentioned in other posts. So I broke down and purchased FoCal ( http://www.reikan.co.uk/focal/ ) and the amount needed was less then what I thought on every lens. So maybe your calibration isn't as accurate as you think?

Again, this may just be me with my bad eyesite, but thought I'd throw that out there. Either way, I hope you getting figured out soon.
 
Just a few of clarifications:
  1. One shot: The subject is static. The AF assumes that the subject is static. The focus is achieved immediately and that's it, you can remove your finger from the back button, it won't keep on focusing.
  2. One shot: The subject is moving. The AF assumes that the subject is static. The photo will be out of focus.
  3. AI Servo: The subject is static: The AF assumes that the subject is moving. The focus will immediately starts tracking the movements. Oops, the subject is static, so now the AF realizes and achieves focus, which is why often the 1st photo is out of focus and the next one in the serie is in focus. Canon is telling you that you are in the wrong mode.
  4. AI Servo: The subject is moving. The AF assumes that the subject is moving. The focus will immediately starts tracking the movements.
  5. AI Focus: The subject is static. The AF assumes that the subject is static. The focus is achieved immediately and that's it.
  6. AI Focus: The subject is moving. The AF assumes that the subject is static. The focus is not achieved. The AF switches to Servo. Which is why often the 1st photo is out of focus and the next one in the serie is in focus. Canon is telling you that you are in the wrong mode.
The difference between the One Shot and the AI Focus. The AF assumes that the subject is static but with the AI Focus the AF will switch to Servo if needed.

Source: Rudy Winston of Canon

--
Thanks
http://foto-biz.com
The Business of Being a Photographer -- Lightroom Q&A
 
AF SHOOTING MODE OPTIONS

One Shot AF

In this mode the AF system is set to focus on a stationary object. Once the system has confirmed sharp focus, a halfpress on the shutter button will lock focus. You can then re-compose (if you wish) before you release the shutter.

AI Servo AF

In this mode the AF system is set to detect a moving subject, focus on it, and maintain focus as you release the shutter. This mode is ideal for subjects moving in
three-dimensional space; that is, toward or away from the camera.

AI Focus AF

The AF system will automatically choose between One Shot AF or AI Servo AF based on whether it perceives the subject to be still or in motion. Keep in mind, however, that because AI Focus may not always be able to discriminate between subject and camera motion, you will have more predictable results if you choose One Shot AF for stationary subjects or AI Servo AF for subjects in motion. Also note that automatic AF point selection and the viewfinder display will function differently depending on whether the EOS 7D is set to One Shot or AI Servo AF.

--
-Joe
 
Anthony Curcione said:
Maybe it was just me, but when I tried to MFA my lenses using the Spyder LensCal target I was misjudging the amount of change needed, even with all the techniques mentioned in other posts. So I broke down and purchased FoCal ( http://www.reikan.co.uk/focal/ ) and the amount needed was less then what I thought on every lens. So maybe your calibration isn't as accurate as you think?

Again, this may just be me with my bad eyesite, but thought I'd throw that out there. Either way, I hope you getting figured out soon.
Click to expand...
I had the same issues. I have always thought there should be software to do this. Finally FoCal came out but it is only for PC. I am waiting for the Mac version and it might be a long time. Until that happens I send my stuff to Canon if need be.

--

Weaseling out of things is important to learn! It's what separates us from the animals. Except the weasel.

Homer Simpson
 
I have had this exact problem and have had the camera back to Canon twice for "electronic adjustment". It still does it occasionally and there is no real explanation why.

I can't understand if it can't lock on a subject you are focusing on why does it confirm lock when it it is front focusing? I would rather have the lens hunt. This happens with a 24-105 and a 70-200 is f4. Anything that is slightly back lit you have to take your time and use a couple of different focus points to nail the shot sometimes. Never had the same problem with my 40D!
Binister said:
Hello,

I purchased my 7D the first month it was released. I have had it in for service once and the standard "electrical adjustment" was made at the service center.

I have done extensive focus testing with it and have never been 100% happy with how often it misses. I have read these forums a long time so I know how heated this debate becomes.

I am sure it has something to do with my technique and I am hoping to get some tips from everyone.

Here is some background:

I shoot Manual 90% of the time and am very comfortable making exposure adjustments on the fly.

I use back-button focus 100% of the time and usually use Servo mode. I am comfortable adjusting the focus point quickly to capture better framing.

The image below is what I often see. I was shooting a friend's child playing and had moved the focus point over his mouth (shooting thirds), focused and shot. I have confirmed in DPP the focus point was over his mouth however the camera obviously focused on his hand.

I know Servo will often focus on the closest subject in the frame but I thought that was only after a new subject enters the frame. Nothing much was moving in this frame.

Any suggestions?
Click to expand...
 
Seriously, the Lens Align photos should be taken to Canon. With the camera. For attention.

And when you go to pick it up, bring the charts and tripod and shoot a series in the shop . (Let the staff control the camera if they think it's your fault.) Problem not fixed - hand it right back.
--
call me Arg
 
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