# 5D Mark iii AF issues



## naterz (Apr 9, 2012)

I've gone through and tried af fine tuning. Tried turning it off. Etc. Here's my issue with my 5d Mark iii camera that I want so desperately to love. Maybe I have a dud? I dunno? I will put the camera on a tripod, point it at a brick wall and focus and shoot, and sometimes it will nail it, and sometimes it will be dreadfully soft. I'm using the center point. I've tried all different focusing modes, and I'm shooting a very contrasty (should be easy to focus on) brick wall. Again, it's about 50/50. Sometimes it nails it. Other times it locks on very fast, which is great. I take the shot, zoom in and see how ugly soft the image is. 

The reason I'm even doing these test is I've taken it on two engagement shoots so far. And have seen this issue. There will be times when it will lock SOLID on exactly what I'm trying to focus on, I'll take the shot and it's awfully soft. Other times it was doing great. So I was thinking it was user error until I set up these very controlled tests shooting at a brick wall. I'm shooting with nice L lenses as well. Any help? What would you do? Would you send it in? Would you return and just get a new one?


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## wickidwombat (Apr 10, 2012)

naterz said:


> I've gone through and tried af fine tuning. Tried turning it off. Etc. Here's my issue with my 5d Mark iii camera that I want so desperately to love. Maybe I have a dud? I dunno? I will put the camera on a tripod, point it at a brick wall and focus and shoot, and sometimes it will nail it, and sometimes it will be dreadfully soft. I'm using the center point. I've tried all different focusing modes, and I'm shooting a very contrasty (should be easy to focus on) brick wall. Again, it's about 50/50. Sometimes it nails it. Other times it locks on very fast, which is great. I take the shot, zoom in and see how ugly soft the image is.
> 
> The reason I'm even doing these test is I've taken it on two engagement shoots so far. And have seen this issue. There will be times when it will lock SOLID on exactly what I'm trying to focus on, I'll take the shot and it's awfully soft. Other times it was doing great. So I was thinking it was user error until I set up these very controlled tests shooting at a brick wall. I'm shooting with nice L lenses as well. Any help? What would you do? Would you send it in? Would you return and just get a new one?


Sounds exactly like the problem I had, I took it back and i'm waiting on a replacement
going back to using my 5dmk2 I NEVER ever thought I would say this but ah my nice reliable 5Dmk2 center point
just nails it every time.

Take it back see if you can get a new one. most people dont seem to have this problem (I think JR also had this problem on his too) but overall most people are reporting accurate focusing so I think is likely a bad unit


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## PhilDrinkwater (Apr 10, 2012)

I Presume you've tried several lenses? All have the same issues?


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## Mt Spokane Photography (Apr 10, 2012)

See which lenses cause the issue. 

Activate the expansion points. If it has difficulty finding focus, you will see the expansion points briefly flash as it calls on them for help. Pg 72-73 of our manual. 

The camera will focus on the center point unless it can't find enough contrast, then the expansion points help out. 

Some lenses are just plain erratic in focusing, even L lenses.


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## wickidwombat (Apr 10, 2012)

Mt Spokane Photography said:


> See which lenses cause the issue.
> 
> Activate the expansion points. If it has difficulty finding focus, you will see the expansion points briefly flash as it calls on them for help. Pg 72-73 of our manual.
> 
> ...



for mine the problem occured on all lenses, it is a good test to see if its hapening accross all your lenses and not just limited to one not playing nice


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## V8Beast (Apr 10, 2012)

Sounds like a dud. Send it back. I haven't done any micro focusing with an of my lenses, and my 5DIII's AF system is dead nuts accurate. A brick wall isn't exactly a challenging subject for the AF system to lock onto. Most people seem happy with their MKIII's, but it sounds like there are some duds out there.


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## naterz (Apr 10, 2012)

Yes I've tried it with multiple lenses and multiple focusing modes, including expansion. The results are very erratic. Sometimes it will be great. Sometime it will totally front focus, and sometimes it will back focus. All without even moving my tripod in front of the brick wall...which like mentioned above, is not hard at all to focus on to. : / I seriously DON'T want to send it back, but I will if I have to. I wish B&H wasn't closed for another week.


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