# Focusing



## climber (Jan 26, 2014)

Hi guys. I saw this video (How To Use AF-On And Back Button Autofocus) where that man talk how to use AF-On button on a camera. How much of you use this technique and how usefull is it?


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## neuroanatomist (Jan 26, 2014)

I use back-button AF. Great for birds (bump-focus), useful for focus recompose. Only downside is if you hand your camera to someone else, but green-square mode cancels back-button AF.


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## Zen (Jan 28, 2014)

neuroanatomist said:


> I use back-button AF. Great for birds (bump-focus), useful for focus recompose. Only downside is if you hand your camera to someone else, but green-square mode cancels back-button AF.




Me too!


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## RustyTheGeek (Feb 2, 2014)

+1 Ditto. Only problem is when you hand the camera to someone else.

Otherwise, I got used to shooting this way years ago. I do quite a bit of low light photography where once I get a focus point sharp, I can shoot several pictures at approx that same distance without losing the focus. In low light you often run into problems with slow focus hunting so shooting without AF happening with every shot is helpful.


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## slclick (Feb 2, 2014)

it's a tough couple of first days but after that you can't go back


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## climber (Feb 3, 2014)

But if I put it in AI Servo mode, then there is no "beep" confirmation. How do you make sure that the object is in focus when shooting stationary objects?

PS: I have 5D mk III and as I know there is no option to make a beep confirmation in AI Servo mode.


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## Viggo (Feb 3, 2014)

climber said:


> But if I put it in AI Servo mode, then there is no "beep" confirmation. How do you make sure that the object is in focus when shooting stationary objects?
> 
> PS: I have 5D mk III and as I know there is no option to make a beep confirmation in AI Servo mode.



You don't need it, it's in focus .. Otherwise you can assign your DOF preview button to switch between Ai and One shot. I don't have any problems shooting stationary subjects with Servo, I have used one shot less than ten shots out of the 70.000 shot with the 1dx and it was the same with the 5d3.

BBF takes a few days to master, but it's not even
Something I think about now, it's automatic.


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## sagittariansrock (Feb 3, 2014)

climber said:


> But if I put it in AI Servo mode, then there is no "beep" confirmation. How do you make sure that the object is in focus when shooting stationary objects?
> 
> PS: I have 5D mk III and as I know there is no option to make a beep confirmation in AI Servo mode.



You can use the AF point "blink"- set it to show up before focusing and once it is focused. Then it will blink at the moment it is focused.


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## climber (Feb 3, 2014)

sagittariansrock said:


> climber said:
> 
> 
> > But if I put it in AI Servo mode, then there is no "beep" confirmation. How do you make sure that the object is in focus when shooting stationary objects?
> ...



I'm not sure but I think that's not possible with AI Servo. Or at least I don't know how to set it.


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## Viggo (Feb 3, 2014)

climber said:


> sagittariansrock said:
> 
> 
> > climber said:
> ...



AF menu>AF5>AF Point display during focusing>selected(focused)


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## jrista (Feb 3, 2014)

neuroanatomist said:


> I use back-button AF. Great for birds (bump-focus), useful for focus recompose. Only downside is if you hand your camera to someone else, but green-square mode cancels back-button AF.



Ditto! And whenver I hand my camera to someone else, I always take the opportunity to teach them about rear-button AF so they can be cool to. 8)

Personally, though, I remap AF-On and * functions. The * button is vastly more convenient for me as an AF on button. I don't use AE lock all that much, so I assign it to AF-On, which is kind of weird to reach given how it is depressed a little relative to the * button. (BTW, this is on a 7D right now.) 

I honestly couldn't live without rear-button AF anymore. I live and die by AI Servo mode...the only times my camera comes out of AI Servo are when I'm doing astrophotography.


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## Zv (Feb 3, 2014)

BBF - love it. Once focus is acquired you can sit relaxed and wait for that perfect shot and still be ready if something crosses your path. It's a street shooter's best buddy. 

For AI Servo it's a must. You can be constantly tracking something without firing a shot. (Technically the half shutter press method can too but how long can you hold your finger there before it cramps up?). 

Oh and you never have to touch the AF/MF switch ever again. It's always in MF until you press the AF-On button.


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## sagittariansrock (Feb 4, 2014)

Viggo said:


> climber said:
> 
> 
> > sagittariansrock said:
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+1. That's how to do it. And yes, it still works with AI servo.


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## cervantes (Feb 6, 2014)

Hi,

I published an article about Configuring your 5D Mark III AF for fast action.
There is also quite a big section about back-button AF AND a quite different way to use it than most guys do.

You maybe want to check it out!

http://www.dpreview.com/articles/9174241280/configuring-your-5d-mark-iii-af-for-fast-action

Greetings!


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## climber (Feb 6, 2014)

cervantes said:


> Hi,
> 
> I published an article about Configuring your 5D Mark III AF for fast action.
> There is also quite a big section about back-button AF AND a quite different way to use it than most guys do.
> ...



Yes, I saw it. Great article. I have already asked you something about focusing in the other thread.


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## mackguyver (Feb 6, 2014)

Zen said:


> neuroanatomist said:
> 
> 
> > I use back-button AF. Great for birds (bump-focus), useful for focus recompose. Only downside is if you hand your camera to someone else, but green-square mode cancels back-button AF.
> ...


Me three! I have so many blurry photos of myself that I actually set C3 to Shutter AF+AE, f/8, Auto-ISO, and other settings to make the shots as idiot proof as possible


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## sagittariansrock (Feb 7, 2014)

mackguyver said:


> Zen said:
> 
> 
> > neuroanatomist said:
> ...



I usually switch to manual, pre focus, pre zoom, set a very small aperture and then give the camera away. Usually works fine.


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