# Auto Focus



## chauncey (Apr 19, 2015)

Assuming that there is sufficient contrast in a subject...can you set-up Canon's AF to detect movement in a scene and lock onto that movement?


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## Marsu42 (Apr 19, 2015)

chauncey said:


> Assuming that there is sufficient contrast in a subject...can you set-up Canon's AF to detect movement in a scene and lock onto that movement?



I can answer that for non-premium cameras like 60d (9-pt af system) and 6d (5d2-type af with 11 pts): No, you can't - these camera's just have "servo af" and don't "track" at all as in locking onto something and handing it over between af points.

Better af system, esp. in 1d-type cameras (and esp. 1dx w/ rgb metering) might do better tough, I'll let the CR heavyweights comment on this.


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## takesome1 (Apr 19, 2015)

Lock on to something not moving and then track it's movement once it starts?
Or lock on to something only because it starts moving?

The first we know the answer is yes. Pick up and lock on moving object yes. Switch from one stationary object or moving object to another that comes in view yes.

The second I have never seen a function mentioned that focus only because of motion, but it would be interesting if such a function exists.


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## chauncey (Apr 19, 2015)

> Or lock on to something only because it starts moving?


That's what I had in mind.


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## Marsu42 (Apr 19, 2015)

chauncey said:


> > Or lock on to something only because it starts moving?
> 
> 
> That's what I had in mind.



That would be the "ai focus" mode that isn't there on premium models for a reason - sounds nice, but doesn't work (at least not for me, nor anyone I've read of).


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## takesome1 (Apr 19, 2015)

There are settings that would simulate what you are asking, for instance a subject moves toward you and becomes the closest object. You can change settings to help in various scenarios.

But what you are proposing you would have to find a setting that might pick up a person who in a crowd suddenly runs away or moves sideways behind other subjects. That one is tougher but certain settings might help.

Doing a word search in the 1Dx manual I see nothing for movement or motion that says it will focus as you suggest.


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## takesome1 (Apr 19, 2015)

Marsu42 said:


> chauncey said:
> 
> 
> > > Or lock on to something only because it starts moving?
> ...



I though "ai focus" would require a point to be focused in single point then it goes in ai servo to track.

If I understand the question, it would be like this scenario. Take a picture of a crowd, then one person in the upper part of the frame either runs forward backwards or sideways and the camera would pick this up and focus on the person because he is moving.


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## Marsu42 (Apr 19, 2015)

takesome1 said:


> I though "ai focus" would require a point to be focused in single point then it goes in ai servo to track.



Well, this ai focus thingy can be enabled with all af pts selected, too (6d).



takesome1 said:


> If I understand the question, it would be like this scenario. Take a picture of a crowd, then one person in the
> upper part of the frame either runs forward backwards or sideways and the camera would pick this up and focus on the person because he is moving.



Right, always good understanding the question . In this case, my answer would be what I often write in "the dawn of mirrorless" threads: The current af system is essentially dumb, even 1dx and such devices can manage some image recognition on selected patterns.

If you want fancy, you have to have the sensor see the image all the time and apply a huge load of image processing power on it - but then, the sky's the limit ("lock on and track all birds with a red point at the end of the wings, please".


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## neuroanatomist (Apr 19, 2015)

chauncey said:


> > Or lock on to something only because it starts moving?
> 
> 
> That's what I had in mind.



In that case, no.


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## Valvebounce (Apr 20, 2015)

Hi Chauncey. 
If you are able to work tethered you might be able to do it with free security camera software, after the workshops where mine is were burgled we looked in to how to set up security cameras, I found some free software out there with motion detection but went with the software that came with the PCI camera connection card. 
I don't remember the names, I found them by searching for free (or maybe open source) security camera software. 
Only issues I can see are the limit of time on live view operation to prevent camera overheat, and whether the software can trigger the focus action in live view. 
Also Magic Lantern or DSLR Controller might be able to do what you want?

Cheers, Graham.


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