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 07 Mar 2018 (Wednesday) 17:21
Search threadPrev/next
sponsored links
(this ad will go away when you log in as a registered member)

7d AF doesn't work, exept in Liveview

 
Valokuva
Mostly Lurking
11 posts
Joined Feb 2018
     
Mar 07, 2018 17:21 |  #1

Hello,

I was wondering if anyone has an experience with following problem..

Canon 7d autofocus doesn't work when used through viewfinder, seems like connection to the lens is somehow disturbed when I move lens AF/MF switch to AF postition. It won't even try to focus (nothing moves) from shutter or AF-ON button, also an aperture blades won't move when depht of field preview button is pressed. I can see and change aperture numbers on display so I think it still sees that lens is connected.

When I flip switch on lens back to MF, I can focus manually (no conf.) and can take a picture. Also aparture blades will move from preview button.

Everything works good when using Liveview.


Don't know about history, got it in that condition. At least looks like new :)

Basic things already tried:
Different settings
Reboot
Firmware update (2.0.6)
Different lenses (all work on other 7d)
Different batteries
Remote control (so not shutter button fault)


Other things done:
Disassembled/assembled few times
Cleaned connectors of ribbon cables of top and middle main boards and the board at the bottom (sorry for not knowing names of all internal components)
Cleaned 2 and 3 pin normal connectors(molex maybe?) on bottom board.
Got about 10 shocks from 300v flash capasitor :)

Just some thoughts:
If focusing sensor at the pentaprism fails does it affect aparture( or at least preview button)?

If there were poor connection between lens and camera AF wouldn't work in Liveview too?

One thing is still disturbing me.. Firmware was already 2.0.6. I updated it but I used the file that was already on CF card that came with camera (I'm lazy sometimes) so what if that file was broken.. I actually think that camera had problem before that file got there but mayby I try another file once I get camera assembeled once again.

One of the ribbon connectors at main board had quite a lot of oxide on it, I belive I got it cleaned but I don't now is it even related to my problem as I don't have diagrams.

I'd like to hear about similar problems and possible solutions to them.
Also if anyone happen to have a knowledge or documentation to figure out electrical routes inside camera please let me know.

Any other suggestions?

Thank you!

Toni




  
  LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as a registered member)
John ­ from ­ PA
Cream of the Crop
7,946 posts
Likes: 469
Joined May 2003
Location: Southeast Pennsylvania
Post edited 3 months ago by John from PA.
     
Mar 07, 2018 17:26 |  #2

Your comment about not knowing its history makes me recommend to set it back to factory defaults and the retest. I would also consider a reflash of the firmware.




  
  LOG IN TO REPLY
Valokuva
THREAD ­ STARTER
Mostly Lurking
11 posts
Joined Feb 2018
     
Mar 07, 2018 17:29 |  #3

Just for the record..
I can see and change focus points in viewfinder. Don't know does it say anything about focus sensor being ok or not..


Toni




  
  LOG IN TO REPLY
Valokuva
THREAD ­ STARTER
Mostly Lurking
11 posts
Joined Feb 2018
     
Mar 07, 2018 17:31 as a reply to  @ John from PA's post |  #4

Thank's.
I got factory defaults already and also updated firmware.. But as I said that firmware was on the card already so I'll download a new one just in case

Toni




  
  LOG IN TO REPLY
Wilt
Reader's Digest Condensed version of War and Peace [POTN Vol 1]
Avatar
40,183 posts
Gallery: 1 photo
Likes: 2023
Joined Aug 2005
Location: Belmont, CA
Post edited 3 months ago by Wilt.
     
Mar 07, 2018 17:38 |  #5

In viewfinder mode, the system diverts light downward to the AF sensor in the base of the camera.
In LiveView mode, the sensor in the base gets no light, so the AF system uses the sensor signals to compute AF.
It could be a malfunction with the AF sensor in the base, which prevents AF detection during viewfinder mode.

But Op says, "also an aperture blades won't move when depht of field preview button is pressed. I can see and change aperture numbers on display so I think it still sees that lens is connected. When I flip switch on lens back to MF, I can focus manually (no conf.) and can take a picture. Also aparture blades will move from preview button."
So I suspect some other issue going on, that causes DOF Preview from activating the aperture blades.


You need to give me OK to edit your image and repost! Keep POTN alive and well with member support https://photography-on-the.net/forum/donate.p​hp
Canon dSLR system, Olympus OM 35mm system, Bronica ETRSi 645 system, Horseman LS 4x5 system, Metz flashes, Dynalite studio lighting, and too many accessories to mention

  
  LOG IN TO REPLY
John ­ from ­ PA
Cream of the Crop
7,946 posts
Likes: 469
Joined May 2003
Location: Southeast Pennsylvania
     
Mar 07, 2018 19:51 |  #6

Valokuva wrote in post #18579907 (external link)
Thank's.
I got factory defaults already and also updated firmware.. But as I said that firmware was on the card already so I'll download a new one just in case

Toni

On the card already makes me wonder, are you running MagicLantern?




  
  LOG IN TO REPLY
TeamSpeed
01010100 01010011
Avatar
33,282 posts
Gallery: 72 photos
Best ofs: 2
Likes: 3543
Joined May 2002
Location: Northern Indiana
Post edited 3 months ago by TeamSpeed.
     
Mar 07, 2018 19:55 |  #7

If you have reset everything, the lens has AF turned on, liveview works at focusing, but using viewfinder/phase detect using the AF ON or half press, the lens won't AF, then there is a problem. This info, combined with the fact that the camera was taken apart a few times with ribbon cables being attached/detached, etc, I will have to say that it is an issue of a connector that is bad/not making contact where phase detect AF module would send AF signals to the lens mount.

This is not a normal thing, and in fact in almost 9 years I have never heard of this particular situation.


Past Equipment | My Gallery (external link)

  
  LOG IN TO REPLY
Valokuva
THREAD ­ STARTER
Mostly Lurking
11 posts
Joined Feb 2018
     
Mar 08, 2018 01:45 |  #8

John from PA wrote in post #18579981 (external link)
On the card already makes me wonder, are you running MagicLantern?

No I don't.. And I actually think that if anyone has done some damage with Magic lantern in the past it would't affect AF only. Am I right?




  
  LOG IN TO REPLY
Valokuva
THREAD ­ STARTER
Mostly Lurking
11 posts
Joined Feb 2018
     
Mar 08, 2018 01:52 as a reply to  @ Wilt's post |  #9

Thank's Wilt. You said what I already new but somehow you made me think.. Think that I still don't know is it DOF preview button itself that doesn't work when lens is on AF or is it aperture blades inside lens that don't move when button is pressed.. Knowing that could locate the problem to lens connection or to the area around AF sensor and DOF button.




  
  LOG IN TO REPLY
Valokuva
THREAD ­ STARTER
Mostly Lurking
11 posts
Joined Feb 2018
     
Mar 08, 2018 02:06 |  #10

TeamSpeed wrote in post #18579983 (external link)
If you have reset everything, the lens has AF turned on, liveview works at focusing, but using viewfinder/phase detect using the AF ON or half press, the lens won't AF, then there is a problem. This info, combined with the fact that the camera was taken apart a few times with ribbon cables being attached/detached, etc, I will have to say that it is an issue of a connector that is bad/not making contact where phase detect AF module would send AF signals to the lens mount.

This is not a normal thing, and in fact in almost 9 years I have never heard of this particular situation.

I'm pretty sure myself too that there is a bad connection somewhere. It seems that it hasn't opened before or atleast it is done using right tools. If I was first to open ot then the problem was there long before.. Also I have reassembled it few times and there is only one issue that remains :)
I believe that only one small pin somewhere is corroded but they are so small and there is quite few of them that it's difficult to find without knowing the right connectors that has to be checked.

I'm an automotive electrician and I may say that 95% of all electrical problems are bad connections of some kind. The rest is a broken components and misunderstandings :)




  
  LOG IN TO REPLY
Valokuva
THREAD ­ STARTER
Mostly Lurking
11 posts
Joined Feb 2018
     
Mar 08, 2018 02:37 |  #11

TeamSpeed wrote in post #18579983 (external link)
I will have to say that it is an issue of a connector that is bad/not making contact where phase detect AF module would send AF signals to the lens mount.

I'm just wondering.. If aperture blades move when lens is on MF so there should be enough "connection" to the lens to move them.
When I switch to AF, power consumption of the lens should not change unless I try to focus so how could bad connection take down the aperture system? (I know it's digital I/Os that is not so easy to fit into basic electrical formulas but still..)

Can anyone confirm or deny that focusing sensor also gives power to aperture motor when used in AF mode?

Toni




  
  LOG IN TO REPLY
TeamSpeed
01010100 01010011
Avatar
33,282 posts
Gallery: 72 photos
Best ofs: 2
Likes: 3543
Joined May 2002
Location: Northern Indiana
Post edited 3 months ago by TeamSpeed. (5 edits in all)
     
Mar 08, 2018 06:01 |  #12

Valokuva wrote in post #18580153 (external link)
I'm just wondering.. If aperture blades move when lens is on MF so there should be enough "connection" to the lens to move them.
When I switch to AF, power consumption of the lens should not change unless I try to focus so how could bad connection take down the aperture system? (I know it's digital I/Os that is not so easy to fit into basic electrical formulas but still..)

Can anyone confirm or deny that focusing sensor also gives power to aperture motor when used in AF mode?

Toni

Moving lens groups to focus will draw more power than closing aperture blades. The fact that LiveView all works and phase detect doesn't, which are two completely different systems, lends itself to a logical conclusion that the board or ribbon cables from the phase detect system has a problem. Liveview uses the sensor to determine lens movement, the shutter closing determines the aperture blades to close (again two different functions here as well), and phase detect uses a different board. My guess is that the phase detect system is compromised and not able to do anything. However the DOF preview not working sounds like a 2nd problem.

Automotive electronics are a bit different (even when you are talking about the onboard computers, unless you are working on the internals of those) than PCBs and ribbon cables and very, very small connectors. I also work with automotive electrical, designing wiring harnesses for accessories and also being a past gearhead getting cars down the track just a bit faster than others. ;)

There could be a tear or break in just one line in that ribbon cable and you may miss it. All it would take is one line somewhere to cause issues. An onboard capacitor or transistor could be corroded too. If there was this level of corrosion in the camera, then I assume it had water damage in the past? Corrosion is so pervasive depending on the salinity of the water that it is often tough to get everything fixed back up.

Sometimes when dealing with compromised hardware such as this, it is better to get another "for parts" camera and start taking the best from each to create one working unit. So if there is a camera out there with a broken rear screen, for example, it might be easier to put the back panel of the almost working camera onto the broken rear panel camera. Again, much like the car industry! I know a guy that bought up wrecked and flooded Teslas, took them completely apart, cleaned up what he could, mixed parts from several to one fully working car, and sold off the other parts. He has a nicely working and good looking Tesla for about $16K, when he was done.

Not sure if this is even detailed enough at this point, but maybe?



Past Equipment | My Gallery (external link)

  
  LOG IN TO REPLY
Valokuva
THREAD ­ STARTER
Mostly Lurking
11 posts
Joined Feb 2018
     
Mar 08, 2018 06:54 |  #13

TeamSpeed wrote in post #18580214 (external link)
Moving lens groups to focus will draw more power than closing aperture blades...

So it's you designing those wiring harnesses I have to repair :lol:
I also deal with internal parts of electronics, not daily though. I have an experience fixing ECUs, ABS contol modules, some sensors etc. but only if damages can be seen and defective components can be identified.

About the subject.. I agree, moving parts in lens draw more power but as I said only moving the switch on lens to AF position is enough to stop aperture blades/or DOF button. No need to press the shutter for the fault to occur.

It might have some minor water damage in the past but never drowned or similar. Just few minor signs of it at lower part of camera. There are not so many gaskets in 7d so it's probably what many other cameras look like that have been outdoor for longer periods of time.
And I agree with you again.. Poor connection at only one pin is probably the reason of all that mess :-|

And thank's for the video, I've seen it before in google but never open it yet. I'll be back in garage in few hours then I'll watch it.

Toni




  
  LOG IN TO REPLY
Ramon-uk
Senior Member
613 posts
Gallery: 41 photos
Likes: 149
Joined Mar 2006
     
Mar 08, 2018 07:09 as a reply to  @ Valokuva's post |  #14

Have you actually tried with another lens ?




  
  LOG IN TO REPLY
Valokuva
THREAD ­ STARTER
Mostly Lurking
11 posts
Joined Feb 2018
     
Mar 08, 2018 07:36 |  #15

Ramon-uk wrote in post #18580237 (external link)
Have you actually tried with another lens ?

Yes I have, three of them :lol: Also 18-55mm that it came with work on other camera.




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

4,672 views & 1 like for this thread
7d AF doesn't work, exept in Liveview
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 shaikh
826 guests, 261 members online
Simultaneous users record so far is 6430, that happened on Dec 03, 2017

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.