Back button focussing, why would you?

[pecrow]

i see a few people using bb focussing and wonder what advantage this gives you and why/when it would be useful, anyone......

 

[buckas]

http://www.talkphotography.co.uk/forums/showthread.php?t=145628&highlight=bbf

 

[pecrow]

right, thanks
so its bb focussing for action and normal button for static is it?

 

[Alzibiff]

so its bb focussing for action and normal button for static is it?

Not read through the thread above but ... not for me!
It's one or the other for everything in my view, there isn't any point switching from one set up to another. Can only lead to a lot of head scratching when the camera doesn't autofocus .. until you realise you haven't got into whatever focus mode you recently switched to.

I have used back button focussing for the last four years or so - started on my 10D - and stuck with it.

Alan

 

[andrewc]

The advantage is that if the shutter button does everything, exposure is set when the button is first pressed but because the subject may move the exposure may not be correct.

Back button makes the focussing independent of the exposure.