Approve the Cookies
This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies and our Privacy Policy.
OK
Index  •   • New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
Guest
New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
Register to forums    Log in

 
FORUMS Canon Cameras, Lenses & Accessories Canon EOS Digital Cameras 
Thread started 13 Apr 2010 (Tuesday) 22:19
Search threadPrev/next
sponsored links
(this ad will go away when you log in as a registered member)

7D - question for people who had focus problems ...

 
wheresdavid
Mostly Lurking
10 posts
Joined Apr 2010
     
Apr 13, 2010 22:19 |  #1

I have a 7D which doesn't seem to be focusing properly and I would like to know from others who had "focus issues":

1) were you able to get the AF repaired to work properly and if so what did the repair center say?

The reason I ask this is that I have been traveling in Asia and Finally I was able to get to Bangkok to get my camera looked at. I told them the problem I was having: soft, oof and front focus/back focus problems with my L series lenses. I showed them examples of the problem. They checked the AF twice and said there were no problems. I had to leave Thailand but the problem continued. Finally I got so fed up of looking at a portfolio of soft shots - (granted there are some sharp shots but very few unless I am looking at shots from my 40D which are sharp) so I returned to Thailand from Laos to get the camera "fixed". I had written Canon US tech support twice explaining my problem and they told me they had never heard of such a problem.

I would like to be able to make sure I know what tests should be done to test the AF system in order to ensure that these tests are being performed when I take my camera to get repaired next Monday, April 19th. All I was told by Canon Thailand was that they tested the AF system on the computer and all was well.

I use single shot AF mode, with a single auto focus or spot focus point, usually the center one. At times it seems like the AF system is picking up the highest contrast area surrounding the selected AF point (again, I am using single AF mode, not expanded). I shoot a lot of portraits and environmental portraits. If I take a fairly close portrait I can get a sharp (but usually not tack sharp compared to my 40) shot. If I take an environmental portrait (the single focus point on the face of the subject) this is where the problems really start - back focus (focuses on a high contrast object behind the subject) , front focus (focuses on a high contrast object in front the subject), soft focus. By the way I shoot in RAW and process using Lightroom 2.6

Any input will greatly appreciated




  
  LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as a registered member)
bsmotril
Goldmember
Avatar
2,532 posts
Gallery: 11 photos
Likes: 337
Joined Feb 2006
Location: Austin TX
     
Apr 13, 2010 22:41 |  #2

Have have you tried the spot focus option for a single point? The actual focus sensor is quite a bit bigger than the square in the viewfinder, and it fill pick up the highest contrast objects it sees. The spot focus option shrinks the sensor so that it is just barely bigger than the square in the viewfinder. Also, if you could post some sample images with the EXIF data intact, that would help. Include a 100% pixel cropped view of a portion of the image where you think it is soft.


Gear List
Galleries: http://www.flickr.com/​photos/smopho/ (external link) --- http://billsmotrilla.z​enfolio.com/ (external link)

  
  LOG IN TO REPLY
wheresdavid
THREAD ­ STARTER
Mostly Lurking
10 posts
Joined Apr 2010
     
Apr 14, 2010 02:58 as a reply to  @ bsmotril's post |  #3

Thanks for the input, yes I do use spot focus most of the time but at times I do switch back to single-point AF mode. You brought up a good point about the focus area being much larger than the "square", I am aware of that but totally spaced out on thinking that may be a cause since I also was getting soft and just plain oof shots, especially when comparing shots with my 40D under similar conditions. So maybe some (all?) of the front back focus issues may be a result of the focus area being larger than what I think it is and thus it isn't actually back/front focusing but rather it is focusing "within" the actual focus area (on the highest contrast area) which is larger than the area I see inside the focus point. I have to keep in mind that I do have an actual front/back focus issue with my 135L lens.

I will upload work on uploading some examples. Thinking out load, I am now wondering if a lot of the soft shots are with my 24-105 wide open at 105mm.

Cheers,

Dave




  
  LOG IN TO REPLY
artyman
Sleepless in Hampshire
Avatar
14,412 posts
Gallery: 17 photos
Likes: 73
Joined Feb 2009
Location: Hampshire UK
     
Apr 14, 2010 03:05 |  #4

The AF system must have some detail with which to work, and from what you say it seems the camera is picking the high contrast area withing your focus point which is what it is designed to do, so I can understand that Canon Thailand said it was OK. You also say your 135 lens is front focusing, so you need to test with a lens that you know is OK. You can of course micro adjust your 135 to correct the front focus on the 7D. Set up a proper test target to check the focusing is the only way.


Art that takes you there. http://www.artyman.co.​uk (external link)
Ken
Canon 7D, 350D, 15-85, 18-55, 75-300, Cosina 100 Macro, Sigma 120-300

  
  LOG IN TO REPLY
riokid
Member
Avatar
31 posts
Joined Mar 2010
Location: Southern California
     
Apr 14, 2010 03:27 |  #5

You may want to bring the 24~105 and the body together to Canon so they can check and calibrate both. Is the perceived focusing problem happening on all your lenses or just one lens?

Good luck :)

dan


Mostly Canon stuff

  
  LOG IN TO REPLY
snyderman
Cream of the Crop
Avatar
7,084 posts
Likes: 8
Joined Nov 2008
Location: Wadsworth, Ohio
     
Apr 14, 2010 08:02 |  #6

I'm one of the 'user-error' morons with a 7D that had focus issues. Much of what you have stated was present with my 7D before a trip to Canon US repair in NJ. Here is a written example of before and after repair issue:

Before repair shooting a bird in tree: Single-point focus, in one shot mode. Aim center focus point squarely on bird and ask camera to focus lens. Take 5 shots. On average, 1 in 5 shots bird would be in focus. The other 4 would randomly focus on something else in the frame, at times, maybe nothing at all in frame would be in focus.

After repair: Same setup, put singlepoint (center) focus point on bird. Five shots in a row with accurate focus on bird. Took 25 shots in single-point (center) in One-Shot and 24 achieved accurate focus.

The same 'random focus' issues showed up with all lenses with similar shooting conditions. Sports shooting, portrait shoots, still things, moving targets, etc. The camera would lock focus instantly, it just wouldn't lock ACCURATE focus most of the time.

Canon repair document said that they adjusted electrical contacts or something of that nature. The document didn't admit an actual REPAIR, but indicated 'adjustments' were made to the camera.

On a note of interest, they reset the camera back to original setup. I'm now starting to see that straying from initial camera setup to my own preferences, i.e., using the back button (*) as focus in AI Servo again causing focus issues. For example, my 70-200 f/2.8L IS lens is constantly 'hunting and jerking' for focus, so I know the camera isn't locking onto accurate focus. Also, when I move the single-point focus away from the center position, the keeper rate goes down.

I sincerely believe there are design issues involved with assigning camera functions and how they relate/interact with the new and improved focus system on the 7D.

What works best: Single point focus (center chosen) in One-Shot mode. This combination produces near 100% accuracy on my repaired 7D. As I move away from this mode and use the other focus features, focus accuracy decreases.

I'll continue to work with the 7D because it's capable of very high-quality results. Getting those results on a consistent basis is apparently something I need to completely understand and get a handle on how everything relates to the 7D focus system design.

dave


Canon 5D2 > 35L-85L-135L

  
  LOG IN TO REPLY
lannes
Goldmember
Avatar
4,370 posts
Likes: 6
Joined Dec 2009
Location: Perth, Australia
     
Apr 14, 2010 08:22 as a reply to  @ snyderman's post |  #7

+1 on the Micro adjust, have a look at this before sending the body in


1Dx, 1DM4, 5DM2, 7D, EOS-M, 8-15L, 17-40L, 24 TSE II, 24-105L, 50L, 85L II, 100L, 135L, 200L f/2.8, 300L f/4, 70-200L II, 70-300L, 400Lf/5.6

  
  LOG IN TO REPLY
tstawarz
Member
79 posts
Joined Dec 2008
     
Apr 14, 2010 08:24 as a reply to  @ snyderman's post |  #8

I had a focus issue with my 7D and my 24-105. I did a micro adjustment because my real life shots were just not right. It took a micro adjustment of -20 to get sharp pictures. I sent the camera and the lens to Canon NJ and they came back perfect. It is now perfect with no adjustment at all. Some of my other lenses needed minor adjustments and some needed none at all. I am so happy with this camera.


5DIII gripped, 24-105L IS, 70-200 f/2.8L IS MKII, 100-400f 4.5-5.6L IS, 100 f/2.8 Macro,580 EX II Flash

  
  LOG IN TO REPLY
riokid
Member
Avatar
31 posts
Joined Mar 2010
Location: Southern California
     
Apr 14, 2010 10:51 |  #9

This link might help if you want to try microadjustment:

https://photography-on-the.net/forum/showthre​ad.php?t=750736

HTH :)

dan


Mostly Canon stuff

  
  LOG IN TO REPLY
wheresdavid
THREAD ­ STARTER
Mostly Lurking
10 posts
Joined Apr 2010
     
Apr 15, 2010 01:24 as a reply to  @ artyman's post |  #10

At times, (I think) the AF is not picking the high contrast area within the autofocus point, it picks the high contrast area outside the AF point. I understand that the actual focus area is larger than the focus point we see in the viewfinder but this occurs when I use single shot AF mode with a single spot AF point.




  
  LOG IN TO REPLY
wheresdavid
THREAD ­ STARTER
Mostly Lurking
10 posts
Joined Apr 2010
     
Apr 15, 2010 01:26 as a reply to  @ riokid's post |  #11

I'm afraid to do that. Last time when I brought the 7D with the 135L for calibration - what they did caused the 135 to be very soft on my 40D. I can't risk my 24-105 not working properly on my 40D. Unfortunately, I only have a few days in Bangkok so I can't risk it. Sorry, I just realized that my responses are going at the bottom of this post and not underneath the post that I am responding to.




  
  LOG IN TO REPLY
shedberg
Goldmember
Avatar
1,122 posts
Likes: 1
Joined Mar 2010
Location: Terrace, B.C. Canada
     
Apr 15, 2010 01:36 |  #12

snyderman wrote in post #9992584 (external link)
On a note of interest, they reset the camera back to original setup. I'm now starting to see that straying from initial camera setup to my own preferences, i.e., using the back button (*) as focus in AI Servo again causing focus issues. For example, my 70-200 f/2.8L IS lens is constantly 'hunting and jerking' for focus, so I know the camera isn't locking onto accurate focus. Also, when I move the single-point focus away from the center position, the keeper rate goes down.

Hey Dave, just to clarify... using the back button focus was causing focus issues? When you use the shutter button half-press it was more accurate?

That's really interesting, I wonder if I should switch back as well...


My Flickr Page (external link)
6D / 7D / 16-35 II / 35 2.0 IS / 60 macro / 85 1.8 / 135 2 / 100-400 / 430EX II

  
  LOG IN TO REPLY
wheresdavid
THREAD ­ STARTER
Mostly Lurking
10 posts
Joined Apr 2010
     
Apr 15, 2010 02:17 as a reply to  @ snyderman's post |  #13

Dave (Snyderman) your problems are exactly the problems I am having! I do shoot in single shot mode with spot AF. I don't lock and recompose. Following this things have improved slightly but I still have a low percentage of "Sharp" photos.




  
  LOG IN TO REPLY
wheresdavid
THREAD ­ STARTER
Mostly Lurking
10 posts
Joined Apr 2010
     
Apr 15, 2010 02:18 as a reply to  @ shedberg's post |  #14

I don't use the back button to focus, I use the shutter release button to focus




  
  LOG IN TO REPLY
wheresdavid
THREAD ­ STARTER
Mostly Lurking
10 posts
Joined Apr 2010
     
Apr 15, 2010 05:04 |  #15

Here are some cropped examples of soft/oof shots. how do you get the autofocus points to show on the photos using DPP?

IMAGE: http://www.fotosbydavid.com/photos/837497896_XYkEd-M.jpg
http://www.fotosbydavi​d.com/photos/837497889​_xG3MH-M.jpg (external link)
http://www.fotosbydavi​d.com/photos/837497882​_qaxJQ-M.jpg (external link)
http://www.fotosbydavi​d.com/photos/837497876​_NyP97-M.jpg (external link)



  
  LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as a registered member)

8,381 views & 0 likes for this thread
7D - question for people who had focus problems ...
FORUMS Canon Cameras, Lenses & Accessories Canon EOS Digital Cameras 
AAA
x 1600
y 1600

Jump to forum...   •  Rules   •  Index   •  New posts   •  RTAT   •  'Best of'   •  Gallery   •  Gear   •  Reviews   •  Member list   •  Polls   •  Image rules   •  Search   •  Password reset

Not a member yet?
Register to forums
Registered members may log in to forums and access all the features: full search, image upload, follow forums, own gear list and ratings, likes, more forums, private messaging, thread follow, notifications, own gallery, all settings, view hosted photos, own reviews, see more and do more... and all is free. Don't be a stranger - register now and start posting!


COOKIES DISCLAIMER: This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies and to our privacy policy.
Privacy policy and cookie usage info.


POWERED BY AMASS forum software 2.1forum software
version 2.1 /
code and design
by Pekka Saarinen ©
for photography-on-the.net

Latest registered member is MaryAxiom
957 guests, 218 members online
Simultaneous users record so far is 15144, that happened on Nov 22, 2018

Photography-on-the.net Digital Photography Forums is the website for photographers and all who love great photos, camera and post processing techniques, gear talk, discussion and sharing. Professionals, hobbyists, newbies and those who don't even own a camera -- all are welcome regardless of skill, favourite brand, gear, gender or age. Registering and usage is free.