# Ai servo inconsistency with zone af on canon 5d3



## KKCFamilyman (May 12, 2014)

I was shooting a 5k for family today. I fired test shots before my group was coming and all were good. When the time came I shot 1/250, f9, iso 400, eval meter, center zone, case 1, burst high. In dpp most of the shots are soft whent they should be sharper.
Camera 5d3
Canon 70-300L
Most were in the 2-300 range.
I am going on a trip in three weeks and am curious if this sounds like a user error or a lens issue?


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## wickidwombat (May 12, 2014)

more likely user error
which AF case were you using?

at f9 everything should have been sharp.


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## KKCFamilyman (May 12, 2014)

wickidwombat said:


> more likely user error
> which AF case were you using?
> 
> at f9 everything should have been sharp.


Case 1


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## wickidwombat (May 12, 2014)

KKCFamilyman said:


> wickidwombat said:
> 
> 
> > more likely user error
> ...



try case 2, i've had better luck using that and i leave it in that mode now pretty much
hang on i'll get a pic of the settings and post it because i did modify it a bit


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## wickidwombat (May 12, 2014)

Here are my settings


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## KKCFamilyman (May 12, 2014)

Thanks I will try that.


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## wickidwombat (May 12, 2014)

also what is a 5k? and can you post any of the pictures you have issues with?

edit 

oh and also are you using back button focus? or not? 
back button focus is considerably better for AI servo than the normal setup


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## wickidwombat (May 12, 2014)

have a look here too

http://shutterfreaks.com/Tips/CanonAIServo.html


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## climber (May 12, 2014)

wickidwombat said:


> also what is a 5k? and can you post any of the pictures you have issues with?
> 
> edit
> 
> ...



Why do you think better? And should he press and hold on back button or just one press for focusing and then let it off before start shooting?


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## wickidwombat (May 12, 2014)

climber said:


> wickidwombat said:
> 
> 
> > also what is a 5k? and can you post any of the pictures you have issues with?
> ...


This is where a lot of people come unstuck with servo 
It only works while you have at lock pressed so you either have to use bb af and hold it the whole time then you can shoot at will (this is the best option) or you have to have your finger hanging in purgatory with the shutter button half pressed while tracking this introduces potential shake and fatigue of your trigger finger and also potential to lose tracking between shoots.
If you let off the af in bb af it will miss focus every time 
So the key rules for servo are
1) learn and use back button at
2) hold af the whole time even when shooting
3) begin tracking early a second or 2 if possible but the new 61 point system is pretty good at grabbing stuff that just pops up if you have the right settings
4) keep an eye on the af confirm dot in the vf it tells you what the servo af is doing


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## Valvebounce (May 12, 2014)

Hi Wikedwombat.
Very good summary of the requirements, nice job, AIServo is definitely one of the best excuses reasons to learn to use BBF! 

Cheers Graham.



wickidwombat said:


> climber said:
> 
> 
> > wickidwombat said:
> ...


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## climber (May 12, 2014)

Thanks.

I know that you have to hold on bb all the time for AI Servo working. But what if you are shooting a group of people like original poster said. If they are still (unmoving), would you just press once to focus and then release it? Or would you holding it all the time?


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## scotia (May 12, 2014)

Is it definitely a focus issue? A shutter speed of 1/250s sounds a bit slow for runners if you want them to be sharp (depends on runner speed, of course, but I tend to find that I need at least 1/500s to avoid motion blur, even for longer distance events).


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## tolusina (May 12, 2014)

wickidwombat said:


> also what is a 5k?......


A 5 kilometer running race or run/walk event.

I'm surprised no one has yet answered this question, knowing that the OP was shooting runners seems pretty relevant to the discussion.




.


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## wickidwombat (May 12, 2014)

climber said:


> Thanks.
> 
> I know that you have to hold on bb all the time for AI Servo working. But what if you are shooting a group of people like original poster said. If they are still (unmoving), would you just press once to focus and then release it? Or would you holding it all the time?



if they are standing still and the af confirm dot in the VF is solid the focus will have been achieved and if you let off the af and shoot it should still be sharp. That is if you are using back button af if you are using the standard setting and you remove your finger from the half press then press to take the picture it will try to refocus as it crosses the half press again
another reason back button rules.


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## wickidwombat (May 12, 2014)

tolusina said:


> wickidwombat said:
> 
> 
> > also what is a 5k?......
> ...


Oh thanks well in that case i think my AF settings should be fine for this, i've found this works well for everything i've tried to shoot with servo so have not seen a need to change the setting since getting it setup
check the other factors i've mentioned in your technique if you are still having issues maybe its the gear
i think 1/250 should be fine for runners although i think panning with a much slower shutter speed of say 1/30 would be pretty cool to try too (but get the servo sorted first  )
bear in mind my first bleeding edge 5Dmk3 had a faulty AF module and couldnt focus on anything but it was obvious from the get go something was wrong with it as it sucked in single shot servo and everything you can imagine. but they swapped the cameras out and the new one has been good as gold for the last couple of years. My wifes 5Dmk3 also had to go in for a lose connection in the lens mount where when a heavy lens was mounted it would lose connectivity and not focus, canon replaced the lens mount and associated electronics and its all good now. So it CAN be the gear too 

hope this all helps KC family man


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## Viggo (May 12, 2014)

Anything slower than 1/1000s for my kids running results in motion blur. I usually keep it set at 1/2000s lower limit.

I've seen hundreds of times that slight motion blur will be disguised as slight missed focus. Usually shutter speed is to slow.

Anyway, I have removed Zone AF and 61pt auto from my options and use only single point and with 4 pt expansion if needed, anything else and I have no control of where focusing is locked. BIF and things against a pure background might work better with Zone, but even then I got a wingtip instead of the birds head in focus.


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## scottkinfw (May 12, 2014)

Try case 2 and maybe use only 9 focus points.

sek


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## wickidwombat (May 12, 2014)

Viggo said:


> Anything slower than 1/1000s for my kids running results in motion blur. I usually keep it set at 1/2000s lower limit.
> 
> I've seen hundreds of times that slight motion blur will be disguised as slight missed focus. Usually shutter speed is to slow.
> 
> Anyway, I have removed Zone AF and 61pt auto from my options and use only single point and with 4 pt expansion if needed, anything else and I have no control of where focusing is locked. BIF and things against a pure background might work better with Zone, but even then I got a wingtip instead of the birds head in focus.


I have to use zone as a minimum for BIF as I'm just not god enough to track them with single point


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## Valvebounce (May 13, 2014)

Hi Wikedwombat. 
I guess I'm not a god either, ;D as I try to use singe point and always miss focus, used to blame the 7D based on what I read about its focus system, then I visited the BIF forum here and saw some of the excellent shots, finally had to accept it was operator error! 
Thanks for your typo, it gave me a chuckle as it still made sense.

Cheers Graham.



wickidwombat said:


> I have to use zone as a minimum for BIF as I'm just not god enough to track them with single point


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## KKCFamilyman (May 13, 2014)

wickidwombat said:


> tolusina said:
> 
> 
> > wickidwombat said:
> ...



Thanks
I will try that. Canon ask me to do a focus test with my lens on both bodies to determine body first then maybe lens but maybe. I am just paranoid because I am going on a 10 day trip soon and if 
I dont send it in soon then I will have to rent a lens. I have to try that bb af and case 2 settings. Also i will try reducing some of my af options. I know the random test shots were fine and when time came all were just oof to notice. Uggh. Also at the 70mm end all was fine but half a block straight in front of me they were off.


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## Nelu (May 13, 2014)

wickidwombat said:


> more likely user error
> which AF case were you using?
> 
> at f9 everything should have been sharp.


Let`s put it this way: f9 will provide a good depth of field but 1/250s is too long of a time for moving subjects, like people running.
I would recommend using f5.6 or f8 and a shorter time, like 1/1000s or 1/500s.
For example for soccer I never go use a time longer than 1/750s and I don`t have any problems with motion blur.
Additionally I would recommend not to use Zone AF at all because the camera will focus on the closest (nearest) subject, which is not always what you want.

Cheers
Nelu


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