July 29, 2014, 07:04:23 PM

Author Topic: Back Button Focussing and AF Points  (Read 2353 times)

Sabaki

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Back Button Focussing and AF Points
« on: April 16, 2014, 06:31:35 AM »
I just attended a Canon Roadshow over the weekend where one of the speakers was extolling the virtues of Back Button Focussing (BBF).

The presenter explained about using BBF to gain sharpness on your subject and then recomposing your frame before engaging the shutter. It seems so logical and more precise to me!

His presentation finally made me 'get' BBF and I've decided to convert. Well, once the muscle memory kicks in
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Back Button Focussing and AF Points
« on: April 16, 2014, 06:31:35 AM »

J.R.

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Re: Back Button Focussing and AF Points
« Reply #1 on: April 16, 2014, 07:44:17 AM »
Yes it is great to be able to have the two functions, AF and shutter release work with separate buttons when you need time between locking focus and releasing the shutter.

However, personally I use both methods depending on what I am shooting. I also believe that benefits of the BBF are overhyped. For most shooting, it makes very little difference which method you use - there are situations where using BBF does little except exercising the thumb ;)
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privatebydesign

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Re: Back Button Focussing and AF Points
« Reply #2 on: April 16, 2014, 08:41:19 AM »
I tried it several times and never got the point, what I do find very useful though is AF button for AF OFF, this does the same thing in that it disconnects the AF from metering when you want, but I found I want them linked much more often than I don't want them linked.

Give both methods a try, most people I have demonstrated the idea to have found it makes more sense than the normal BBF.
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johnf3f

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Re: Back Button Focussing and AF Points
« Reply #3 on: April 16, 2014, 08:48:17 AM »
It took me quite a while to be convinced to try BBF, I was very skeptical! Well now I am happily eating my words, it is much more flexible - once you get used to it!

neuroanatomist

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Re: Back Button Focussing and AF Points
« Reply #4 on: April 16, 2014, 08:55:14 AM »
It took me quite a while to be convinced to try BBF, I was very skeptical! Well now I am happily eating my words, it is much more flexible - once you get used to it!

Agreed.  I've tried the AF-OFF approach, but I don't find it as useful.
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privatebydesign

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Re: Back Button Focussing and AF Points
« Reply #5 on: April 16, 2014, 09:07:39 AM »
It took me quite a while to be convinced to try BBF, I was very skeptical! Well now I am happily eating my words, it is much more flexible - once you get used to it!

Agreed.  I've tried the AF-OFF approach, but I don't find it as useful.

I think its usefulness depends on your general subject matter, if you regularly shoot sports, BIF and other dynamic subjects it makes much more sense and once you are used to a way of doing it it makes sense to just use that approach for everything. If you shoot less dynamic subjects and have a camera with good off center AF points then it becomes less important, indeed it is the focus recompose scenario where I want to place the focus point out to the edge of the frame that I use BBOFF most. (I just registered BBOFF as a trademark  :) )
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neuroanatomist

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Re: Back Button Focussing and AF Points
« Reply #6 on: April 16, 2014, 09:24:45 AM »
I think its usefulness depends on your general subject matter, if you regularly shoot sports, BIF and other dynamic subjects it makes much more sense and once you are used to a way of doing it it makes sense to just use that approach for everything.

That makes sense.  Most of what I shoot is pretty dynamic (birds, kids, etc.), and when I'm shooting static subjects, I'm often on a tripod and using Live View anyway.
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Re: Back Button Focussing and AF Points
« Reply #6 on: April 16, 2014, 09:24:45 AM »

AcutancePhotography

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Re: Back Button Focussing and AF Points
« Reply #7 on: April 16, 2014, 10:22:23 AM »
Like most things in photography, there is no best technique.  A lot of togs use BBF and a lot of togs never use it.  Both groups are happy.

Since I do must of my stuff on a tripod, I find using the BBF and EL buttons easier to use.  The advantage of using the shutter button is that one button does two separate functions.  The disadvantage of using the shutter button is that one button does two seperate functions.  ;D

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mackguyver

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Re: Back Button Focussing and AF Points
« Reply #8 on: April 16, 2014, 10:55:47 AM »
I think its usefulness depends on your general subject matter, if you regularly shoot sports, BIF and other dynamic subjects it makes much more sense and once you are used to a way of doing it it makes sense to just use that approach for everything.

That makes sense.  Most of what I shoot is pretty dynamic (birds, kids, etc.), and when I'm shooting static subjects, I'm often on a tripod and using Live View anyway.
+1 though I use BBF so much for wildlife that it feels alien to me to press the shutter to focus now, even for static subjects.  There is one huge danger to using BBF.  If you hand someone your camera the shots will be out of focus.  I have lots of blurry photos of me & my wife to prove it! 
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cid

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Re: Back Button Focussing and AF Points
« Reply #9 on: April 16, 2014, 11:39:31 AM »
I think its usefulness depends on your general subject matter, if you regularly shoot sports, BIF and other dynamic subjects it makes much more sense and once you are used to a way of doing it it makes sense to just use that approach for everything.

That makes sense.  Most of what I shoot is pretty dynamic (birds, kids, etc.), and when I'm shooting static subjects, I'm often on a tripod and using Live View anyway.
+1 though I use BBF so much for wildlife that it feels alien to me to press the shutter to focus now, even for static subjects.  There is one huge danger to using BBF.  If you hand someone your camera the shots will be out of focus.  I have lots of blurry photos of me & my wife to prove it! 

I have one custom mode registered that doesn't use BBF, in AI servo mode, zone focussing and switch to it when I want someone to take a photo of me  ;)
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mackguyver

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Re: Back Button Focussing and AF Points
« Reply #10 on: April 16, 2014, 11:44:56 AM »
I think its usefulness depends on your general subject matter, if you regularly shoot sports, BIF and other dynamic subjects it makes much more sense and once you are used to a way of doing it it makes sense to just use that approach for everything.

That makes sense.  Most of what I shoot is pretty dynamic (birds, kids, etc.), and when I'm shooting static subjects, I'm often on a tripod and using Live View anyway.
+1 though I use BBF so much for wildlife that it feels alien to me to press the shutter to focus now, even for static subjects.  There is one huge danger to using BBF.  If you hand someone your camera the shots will be out of focus.  I have lots of blurry photos of me & my wife to prove it! 

I have one custom mode registered that doesn't use BBF, in AI servo mode, zone focussing and switch to it when I want someone to take a photo of me  ;)
Yep, that's what I did, too :)
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cid

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Re: Back Button Focussing and AF Points
« Reply #11 on: April 16, 2014, 12:01:26 PM »
I think its usefulness depends on your general subject matter, if you regularly shoot sports, BIF and other dynamic subjects it makes much more sense and once you are used to a way of doing it it makes sense to just use that approach for everything.

That makes sense.  Most of what I shoot is pretty dynamic (birds, kids, etc.), and when I'm shooting static subjects, I'm often on a tripod and using Live View anyway.
+1 though I use BBF so much for wildlife that it feels alien to me to press the shutter to focus now, even for static subjects.  There is one huge danger to using BBF.  If you hand someone your camera the shots will be out of focus.  I have lots of blurry photos of me & my wife to prove it! 

I have one custom mode registered that doesn't use BBF, in AI servo mode, zone focussing and switch to it when I want someone to take a photo of me  ;)
Yep, that's what I did, too :)
Oh and I should mention I use it primarily for handheld closeups/macro  ;)
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JPAZ

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Re: Back Button Focussing and AF Points
« Reply #12 on: April 16, 2014, 12:11:28 PM »
I'm "hooked" on BBF.  Not better or worse, just what now works for me.  I recently got more aggressive using differing focus points, as well (had been center focus then recompose) and really appreciate the versatility this brings to the 5diii.  Still training my fingers to find the button I want when I want it, but it is getting to be second nature.

And, I've gotten used to switching to the green square when I hand off the camera for someone to take a shot of us.  Yeah, DOF not always ideal but the camera does a pretty good job of setting it up and exposing.
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Re: Back Button Focussing and AF Points
« Reply #12 on: April 16, 2014, 12:11:28 PM »

Sabaki

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Re: Back Button Focussing and AF Points
« Reply #13 on: April 18, 2014, 11:42:21 AM »
Thank you everybody so much for your feedback.

I am predominantly an action photographer, BIF, macro and other wild life so I'll keep an open mind as I go forward.

Quick question: Using BBF, is the camera's AF performance still relevant? Number of AF points etc?
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AcutancePhotography

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Re: Back Button Focussing and AF Points
« Reply #14 on: April 18, 2014, 12:13:27 PM »

Quick question: Using BBF, is the camera's AF performance still relevant? Number of AF points etc?

For all practical purposes the only thing BBF does is, if set up this way, to deactivate the shutter button from activating the AF and set up the back button.

There are some differences depending on how you set the AF servo mode, but the performance of AF and the number of AF points should not change whether you are using the shutter button or BBF.
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Re: Back Button Focussing and AF Points
« Reply #14 on: April 18, 2014, 12:13:27 PM »