Back Button Focus

[Eric Patdu]

I've just learned about the Back Button Focus when I've heard Art Morris mention it on his video on B&H.

I tried reading more about it but is confused about what settings is best for bird photography.

I guess it's either:

2: Metering start / Meter + AF start
3: AE Lock / Metering + AF start

but don't really know which to use.

Can those who use Back Button Focus share what setting they use and why?


Thanks,
Eric

[Ed Cordes]

I use BBF all the time on both my 7D and 1D4. The shutter is used to meter and release the shutter. I have the AF function set to AI Servo so that if I press the back button once it acts like one shot. If I hold it down it works like servo. The IS is activated with either the back button or the shutter button. I really like the fast selection between servo and one shot this arrangement offers. I also like the separation metering from AF. It took a day or so to get used to it, but now it is totally natural.

[Doug Brown]

I prefer metering/metering + AF. You've always got both one shot and AI Servo available.

[Eric Patdu]

Thanks guys! I'll try the setting you suggested.... and I just might not go back to shutter button focus. :S3:

[shane shacaluga]

I have been trying this for the last week and now I am hooked. its great for manual macro work too as you can do a quick focus then use your body to make the final adjustment before the shot

[Daniel Cadieux]

Back button focus should be made default mode on new cameras :S3:.

[John Chardine]

I use back-button focus most of the time but when I'm shooting birds in flight I turn AF-ON back to the shutter button. I find the ergonomics a little easier for BIF. I have this in the Custom menu so it's dead easy to switch back and forth.

[Gary Kinard]

It is very good and habit forming. Funny I just bought a new camera body and that is all I thought about when I looked at it. LOL

[andresleon]

My first post in this forum. I had heard of back button focus but never really understood it until I heard Art talk about it in the Tampa seminar this past weekend. I went ahead and started using it yesterday and have to admit that it is a bit hard to get used to it. I missed a few good shots because of I forgot to press the back button. That being said, I now realize the tremendous benefit it has to offer due to the fact that you can now one-shoot and AI servo focus without having to switch modes. That is a huge advantage! I know that it will take time for this action to become second nature, but I see the value in it.

[Diane Miller]

I finally got BBF through my head a couple of years ago and never went back. I love it! But I have one nitpick -- I'd appreciate comments on it from the more advanced and experienced users here.

Initially, I always left the camera set to AI Servo, but there is some "jitter" in the focus in that mode (Canon 5D Mk II and Mk III), and if I used a brief press and release of the back button sometimes the focus was a little off. Several repeats gave slightly different focus. (Controlled conditions where a small difference would show, and, yes, focus calibrated for each lens and body.)

So now when I'm shooting a still subject where focus is critical and I want max detail, I go back to One Shot, still using the back button though. There's time for the switch in that situation. But the default mode in any situation where action is possible is AI Servo.

[van bogaert erik]

so that if I press the back button once it acts like one shot. The IS is activated with either the back button or the shutter button. .

so when you do like the above you loose time i reckon , because you stopt IS (let go of the back button) and have to start it again with the schutter ?

[Daniel Cadieux]

so when you do like the above you loose time i reckon , because you stopt IS (let go of the back button) and have to start it again with the schutter ?

It's the same with the shutter button if you let it go though, so you are not losing any more time.

With back button, if you keep the shutter button half depressed this keeps the IS going (and locks metering if you are setup to do so). BTW, I cannot say that I've ever missed a shot due to IS having to start.

[van bogaert erik]

1) i have set the AF on the rear button and shutter for metering and to take the picture ; when i NOT press halfway the shutter button , so only the AF rear button : is the IS then activated also ? or is this only active when i press the shutter button halfway ?

2) In the case that the IS is activated also with the rear buttony ; Is it than necessary to press the shutter button always halfway when focusing with the AF rear button or can i press it only complete to take the picture ?

[Diane Miller]

Yes, IS is activated when you press the rear button. No need to press the shutter button until you want to take the picture.

You can also press the rear button to focus, then release it and recompose, and then press the shutter button to take the picture. IS will remain on for a few seconds after letting go of the back button, and of course you don't want the distance to the focus point on the subject to change before you take the picture.

Make sure you are in AI Servo (Canon) or the Nikon equivalent (Continuous Focus?) If you are always going to use BB focus, leave it there.