# AI Servo AF not reliable in 5D4



## drolo61 (May 2, 2018)

Dear all,

I have had an intense weekend shooting children's hats for my wifes company.

I use BBF with AI servo to be able to follow the running little beauties. For the first time I have a relatively lower rate of critically sharp images (70-200 2.8 II IS), although working faster than 1/200 and ~ at least 4.0

The "non-keepers" happen also with more or less static subjects and I have no real idea why.

Nevertheless I noticed, that very subtle movements seem not to be detected/followed by the AI Servo. Has anyone encountered a similar behaviour? Will try to go back to <One Shot> to see, if this brings up my rate of keepers in these situations.

Sending the body to CPS is no option, as we have to finalise the shooting befor May 25th.

Second option of cause can be rent, but so far we do get the keepers needed and budget is scarce.

Thanks for any help - as always highly apprechiated

Cheers
Olaf


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## Hector1970 (May 2, 2018)

Were you using back button focusing?


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## drolo61 (May 2, 2018)

Yes, sorry for my shorthand "BBF"


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## Valvebounce (May 2, 2018)

Hi Olaf. 
Just a thought, might you have accidentally selected AI Focus, this lets the camera decide whether things are static or moving, there must be a reason Canon left it off the 1D series bodies! 

Cheers, Graham.


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## drolo61 (May 2, 2018)

Hi Graham,

I will check that - I intend to work with AI Servo, as I need to catch playing kids. 

My isse is, that very small movements are not (always) detected (properly). 
Or I have more difficulties steadying my lens than I would like to have, I dont know.

Thanks
Olaf


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## dab963 (May 2, 2018)

Hi,
try these settings:

AI Servo Tracking Sensitivity +2
AI Servo 1st image priority "Focus"
AI Servo 2nd image priority +1 or +2

Best, Daniele


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## Handrews (May 2, 2018)

Hi there,

It might also be useful if you could provide some info about the lighting conditions and distance from subjects.
If lighting is dim, AI servo tends to be less reliable than One shot. 
What about the number of AF points? If set to one point, try to increase the number of AF points and see if it makes a difference.
The distance to subjects should also be taken into account, if the kids are running towards you, 1/200 is not enough.

Hope these help!


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## BillB (May 2, 2018)

drolo61 said:


> Dear all,
> 
> I have had an intense weekend shooting children's hats for my wifes company.
> 
> ...



If very subtle motions are an issue, maybe shutter speed is the problem, especially if you are pretty close to the subject. Can you tell if the problem photos are related to slower shutter speed? Anyway, it might be good to try faster shutter speeds.

Also, the 5DIV manual around pages 127-130 describes possible AI servo settings. Also, It might be useful to experiment with manually selecting a single point with expansion to the surrounding points.


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## drolo61 (May 2, 2018)

dear all,

thanks for the valuable input.
I will check all recommended details tonight.
The next shooting will be tomorrw afternoon and I will let you know of the outcome.

@daniele - will use your settings and have already re-read the manual in the sections @BillB pointed to

Lightning conditions where mid-ok I would say. Overcast skies during normal daylight. Lightning was ok at ISO 800, 1/320 and F5.6. I used a softbox to light the faces under the hats. I use <one AF spot> point, as I need to get "under the brim". Sometimes I can understand what went wrong - I used the "show focus point" LR plug-in.

If I hit the brim of a cap because the head (or I) moved slightly, than out-of-focus is expected behaviour.

@handrews - it is for this accuracy needed, that I did not (yet) expand the numer of points. In the manual the described behaviour of such settings is that focus will be locked on the nearst part of the subject - in most cases brim or nose but the intended eye. 

But sometimes - even with the focus point right on target - I get miss focussed shots.

I will show examples, should the problem still be present after the tweeaks have been applied and the shooting.
is done.

Enjoy your day, people, and thanks again for the fast responses.


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## Don Haines (May 2, 2018)

I have no specific experience with the 5D4, but in other cameras I have noticed that while AI Servo works well on moving subjects, it seems to fail on stationary or slow moving ones.... I tend to use the custom functions for the camera, and set up C2 with Ai Servo for moving objects and to set up 1 shot in C1 for stationary objects.


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## Mikehit (May 2, 2018)

Don Haines said:


> I have no specific experience with the 5D4, but in other cameras I have noticed that while AI Servo works well on moving subjects, it seems to fail on stationary or slow moving ones.... I tend to use the custom functions for the camera, and set up C2 with Ai Servo for moving objects and to set up 1 shot in C1 for stationary objects.



Using AI Focus on stationary subjects is a recognised issue when trying for a very shallow DOF because the algorithm is hunting for movement that is not there and the shallow DOF shows this up. 
As has been mentioned above, Canon will tell you that the best AF is achieved using stationary subject, centre point, one shot focus on good contrast subject - anything from there will not be as good, but in a vast majority of conditions will be good enough. 
Also remember that the AF area in the focussing mechanism is nearly always slightly larger than what you see in the viewfinder so if you are focusing on the (relatively) low contrast in the shadow of a hat you may see some variability.


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## Random Orbits (May 2, 2018)

I've used the 5D4 + 70-200 IS II for soccer and portraits with no problem (AI servo and one shot).

Have you tried checking AFMA? If you have a tripod, mount the camera and try focusing in one shot on a high contrast static subject using the center point with spot. Then switch over to live view and focus on the same subject. The "sharpness" on the magnified live view should not change much. If it is, then the body/lens combo needs to be AFMAed. I'm assuming the body is rental or a new purchase and that the 70-200 works well with your other cameras. If it works well for one shot without AFMA then I'd suggest playing with the use cases for AI servo or trying for a higher contrast target at the same distance.


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## YuengLinger (May 2, 2018)

Have you spent time testing the camera and lens in good light under controlled condtions? That is, with a subject first walking towards you, then running towards you, then moving a little more erratically? 

Or are you basing your assessment only on the results of a recent "live" photo session?

You need to eliminate as many variables as possible, then try making some changes to your AF scenario settings. And also try with more than one lens to determine if the lens or the body is a source of problems.

Keeping up with kids in the viewfinder isn't always easy...I have been having better luck with the four-point spread when they are running around. With a 70-200mm, once I get beyond 85mm, just a tiny motion of the lens results in a big change to where the AF spot hits, and with little kids moving erratically, I sometimes move too far off the target and get the background.

And don't forget to blow clean the AF sensor area! That solved some similar issues I was having a few months back.

But you can't know if it is technique or a hardware problem until you have patiently gone through a controlled practice session with different scenarios.

As far as sending to CPS, they usually have equipment back to me within 10 days of me sending it to them, which is still close but should give you enough time if you get it out this afternoon or tomorrow.

Do you have a backup camera that might be good enough?

Sounds like a frustrating time to discover an issue, but you might be able to solve it with testing and changing settings. 

Check out this link to go through a checklist and maybe get some more ideas...

https://lensvid.com/technique/a-guide-to-solving-autofocus-problems/


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## LDS (May 2, 2018)

This is for the 5DIII but should still be useful:

https://www.learn.usa.canon.com/app/pdfs/quickguides/CDLC_EOS-1DX_Mark_III_AF_tracking_QuickGuide.pdf

Especially, selecting the proper "case" (or selecting proper parameters directly) for the subject is important, because it changes how the AF reacts to change in speed and direction. Especially "Acceleration/Deceleration Sensitivity" could impact how the AF behaves when subject in movement stop.


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## drolo61 (May 2, 2018)

@YuengLinger - camera with lens has been ALMAed via Focal - the set performed well - testing has been done ~6 month ago - will re-test over the weekend, if issue continues - current assessment is based on live shoot - will blow clean and stick to <One shot> for really critical pictures - unfortunately currently no back-up, but get one - there is enough keepers to survive this job ;-)

@randomorbits - AFMA about 6month old and (at the time) spot on - will re-do

@mikehit - will go switch more frequently between <one shot> and <AI servo> depending on the complexity of the situation - will be an additional challenge on top of keeping track of the subject(s) - I do this for ~15 years now and the ambition of my art director (alias wife) always raises with the quality we produced last time ;-) - Thanks for mentioning the larger area covered - that may be the clue I have been looking for - will try to get some safety margin away from the brims...

@DonHaines - I recall, insoired by your idea for C1 and C2, that there has been a You Tube tutorial that showed how to configure one of the buttons to switch specifically between these two modes <One shot> and <AF servo> - will share if I find it

@all - thanks people ;.-)


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## Mt Spokane Photography (May 2, 2018)

Focus issues that suddenly pop up can often be traced to dust on the AF sensor that sits behind the mirror at the bottom of the camera. You can use a rocket blower to try and dislodge any dust or debris, be gentle. 

Google how to clean it if necessary.

Thats about the only thing that can be serviced by the user.


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## sebasan (May 2, 2018)

Hi, my two cents, there are also some buttons that you can configure to change AI Servo to One Shot or viceversa. In situations when the subject is almost static, you can change your configuration of AF without changing from C1 to C2 or similar.


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## unfocused (May 2, 2018)

Personally, I think people are making this too complicated.

I doubt if one-shot vs. servo is your problem.

First, how many autofocus points are you using? One point, expanded, zone, all? With moving subjects, one of the expanded points is usually best. 

Second, what autofocus case are you using? If it's just one child then you should set it to track on the subject. The default case is pretty good, but it doesn't hurt to try others. 

Finally, be realistic about both depth of field and shutter speed. Getting a running child's eye in focus at f2.8 is no small feat. Nor is stopping the action if they are hyperactive. 

Finally, the high pass filter is your friend. Learn to use it. Short tutorial: After your adjustments are all done in Photoshop, copy everything and merge the copied layers into a single layer (always copy, so you preserve the original layers in case you need to go back.) 

Duplicate the layer. Go to blending modes, choose "hard light." Go to filters, pick High Pass. Choose a fairly small amount like 2-3 px. Compare the image with the high pass layer on and off. If you've done it right, you will be amazed at how much sharper the eyes look. 

Now, add a black mask to the high pass layer, so everything is obscured. Then paint the mask white for the eyes, mouth, hair and other details you want sharp. 

High pass will increase the perceived noise, but if you are shooting at ISO 400 or so, it won't be noticeable in the final product. I've saved hundreds of images this way.


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## foo (May 2, 2018)

drolo61 said:


> @DonHaines - I recall, insoired by your idea for C1 and C2, that there has been a You Tube tutorial that showed how to configure one of the buttons to switch specifically between these two modes <One shot> and <AF servo> - will share if I find it



The manual tells you how, but relatively easy to do in the button config menu. You can only do it with certain buttons though.

Two ways to set the button up, either it toggles the mode every time you press it, or hold it down for AI servo when you're in one-shot, release and you go back. Possibly other variations, but that's the way I use it.

If I recall, you can do much more than just flip the mode, you can also configure some (all?) of the settings when you hit the button which allows you to have different subsets of AI Servo on a couple of different buttons. So quite versatile assuming you can remember what you programmed each button to do - I can't really so tend to stick with just the one.


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## Don Haines (May 2, 2018)

foo said:


> drolo61 said:
> 
> 
> > @DonHaines - I recall, insoired by your idea for C1 and C2, that there has been a You Tube tutorial that showed how to configure one of the buttons to switch specifically between these two modes <One shot> and <AF servo> - will share if I find it
> ...



For me, it was easier to remember.... C1 is still, C2 is moving.... and for the still targets I am on one AF point, for the moving it is the central zone (7D2) or all the points (6D2). This way I am a bit more consistent across cameras...


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## drolo61 (May 4, 2018)

Dear all,

Shooting yesterday had way improved keeper rates.

What I did - blowing the AF sensor area, going closing the apperture to f 7.1 to f10 (instead of 4-5.6) and tried to keep a better "safety margin" when trying to go "under the brim".

Some pictures attached from before 2CONSULTATION2, after to follow.
Unedited JPEG standard exports from LR with size restriction.

Thank you for the helpful comments and suggestions.
BTW: will go to the C1 and C2 suggestion for distinctly different settings for <still> and <moving>


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## Hector1970 (May 15, 2018)

Interesting topic. 
I'd have always said the 5DIV had a good focusing system but I have found putting it to more complicated tests that the 7DII focuses better.
I'm not sure which has the more advanced focusing system


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## Ah-Keong (May 16, 2018)

Not sure if this help.
Coming from the 7D2, if the three settings (tracking sensitivity=lock-on responsiveness, accel/decal tracking=erratic motion, AF pt auto switching=handover trigger of using more AF squares) does not work,

you can try setting the AI servo 1st image priority to Release and AI servo 2nd image priority to Focus. This would help for faster subjects or complex background.

This would help the 1st shot to go off faster while taking more time for 2nd and subsequent frames for the processor to do the focusing.

Another would be using the 5-point assisted AF squares. For the three settings, I would duplicate into a custom function to play around so as not to play around the 6 template cases together with the two AI servo priority options


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## fullstop (May 31, 2018)

on 5D IV maybe "face tracking AF" (in live view mode) might work well enough in the situation described in starting post? possibly a quicker/less frustrating solution than trying to find the one right combination of servo-af custom settings. would also eliminate any potential AFMA issues. 

well working "Eye Tracking AF" would really be the easiest solution, but not available on 5D4 or any other Canon DSLR (yet) ... Canon EOS M50 has it ... or Sony. 

But have not tried it myself (yet). Don't know if/how well it would work with faces in shade under hat brim. I do however share the frustration of trying to find the best combination of Canon Servo AF custom settings (5D3 here) for a given capturing situation, under time pressure, in the field. "needle in a huge haystack". i would very much prefer not having to fiddle around with it, but rather have a camera deserving of the "AI servo AF" moniker! A camera that "intelligently" uses most appropriate AF mode and options on its own and perfectly tracks the (left or right) eye of a person after i select it with a tap on the touchscreen and from there on delivers shots perfectly focused on that very eye - at least as long as it is visible in the frame and opened. 

AT the very minimum, it would help immensely if Canon would finally show AF fields correctly sized and positioned, rather than real AF fields being LARGER than the marking white rectangles in viewfinder / on LCD indicate. If in novative Canon is unable to correctly match up marking and real AF field, then at least make the marking box LARGER than the real AF field, not the other way round. Current implementation is the worst of all options. GRRR.


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## pwp (May 31, 2018)

drolo61 said:


> I have had an intense weekend shooting children's hats for my wife's company.
> 
> I use BBF with AI servo to be able to follow the running little beauties. For the first time I have a relatively lower rate of critically sharp images (70-200 2.8 II IS), although working faster than 1/200 and ~ at least 4.0
> 
> ...


I have nothing but praise for the 5D4 AI Servo performance. Even in low light shoots such as a dress rehearsal earlier this week, the keeper rate was reassuringly high. For this particular job I was running four bodies (not all at once!) the 5D4 with 24-70 f/2.8II, 1DX with 70-200 f/2.8 is II, 7DII with 300 f/2.8is and an amazing Panasonic G9 with a brand new 43.5 f/1.7 set to auto iso. All bodies were on AI Servo focus. For a good look, all lens apertures were either wide open or just one click down.

So I'd be inclined to think your low keeper rate is linked to user error. The first thing I see is shutter speed, with the 70-200 you really need to get that shutter speed up a lot, particularly with fast moving children. The 5D4 may have actually focused accurately, but motion blur lost the shot for you. For the job you've described, I'd be using single AF point and keeping that point right on the subject's eyes. At the most, I just might have chosen to expand that AF point to seven in Custom Functions, but I generally only do that for track and field athletics and sometimes football. 

I see in your later post you're shooting stopped right down to f/10. _Hmmm_, not really the best idea unless you're chasing a certain look, I'd be shooting your project at f/3.5 or f/4 at the most. This has the multiple benefits of blurred out backgrounds, a faster shutter speed and lower iso. 

Regarding the keeper rate success at the dress rehearsal, all four cameras were very satisfyingly high. The surprise winner was the recently purchased Panasonic G9 with the 43.5mm f/1.7, (87mm FF equivalent) mostly shot wide open. Interestingly the G9 files comfortably outperformed the 7D MkII at equivalent iso. Next best was the remarkable 1DX, followed almost line-ball with the 5D Mk4 and the 7DII not far behind. This is likely a lot to do with inadequate shutter speed with the 480mm equivalent focal length with the 300mm lens on the x1.6 crop APS-C body. 

In all cases I used the default AF servo Case setting. 

-pw


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## YuengLinger (May 31, 2018)

pwp said:


> drolo61 said:
> 
> 
> > I have had an intense weekend shooting children's hats for my wife's company.
> ...



I hear you, -pwp, but I've had enough odd things happen with gadgets to no longer "be inclined" to blame the user.


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## klickflip (Jun 6, 2018)

Similarly becoming more sceptical of 5`d4 focusing the more I use mine . 

I’ll post a new tread with my current problems which are in studio still life setting and it can be shocking ...


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