7D Back Button AF?????

Hi
can you set the 7D to have the Back Button AF ? I found how to get it to Af using the back button, but it still meters, I am so confused.

See the manual Page 217

Yup, you can definitely turn off metering on the back button, and have the half-press of the shutter button take care of it. There's a whole menu screen for assigning button actions--easy to reach from custom functions as well.

I still can not find it, I can turn off af ion the front button, but can not figure out how to stop the metering on the back AF-on button

peregrineflier wrote in post #10888666
I still can not find it, I can turn off af ion the front button, but can not figure out how to stop the metering on the back AF-on button

I use the * button for focus on my 7d.

malla1962 wrote in post #10888765
I use the * button for focus on my 7d.

Same

You can't turn off metering when you are focusing. Why would you?
You can turn off focusing when you are metering with the half-press of the trigger button, though.

If you use AF-ON (properly labelled for it) or * (legacy solution for when cameras didn't have AF-ON) is of course up to you. When shooting action I have focusing with selected AF point on AF-ON and with registered Home Point on *.

So you can actually have both.

apersson850 wrote in post #10888982
You can't turn off metering when you are focusing. Why would you?
You can turn off focusing when you are metering with the half-press of the trigger button, though.

If you use AF-ON (properly labelled for it) or * (legacy solution for when cameras didn't have AF-ON) is of course up to you. When shooting action I have focusing with selected AF point on AF-ON and with registered Home Point on *.

So you can actually have both.

That sounds like exactly how I would have it... How to you register a Home Point?

User's manual page 219.

Select a single point, hold AF point selection button and press lamp button on top.
The registration can be cancelled by pressing AF select button and ISO button at the same time.

If you use orientation dependent AF point selection, you'll have to register Home Points (HP) for all orientations.
When you set AF-ON and/or * to autofocus, you can press INFO to get deeper into the details, and there select with which point they should focus. You can also select if pressing the joystick should go to HP or not.

The registered point will be shown as a small dot in the viewfinder.

Last time I had good use for this was when shooting racing cars going in and out of a hairpin. For composition reasons, I didn't want to use the center AF point, but one a bit to the side. But the side changed when the cars changed direction in the hairpin. So by just selecting a point to the left and registering a point to the right, I could hold * when going into the hairpin and just changed to AF-ON when going out. A flick of the thumb while I tracked the car in the viewfinder.

/\ Awesome.

Never knew that, and could never find the way to set the 'Home Point; in the manual.

apersson850 wrote in post #10889309
User's manual page 219.

Select a single point, hold AF point selection button and press lamp button on top.
The registration can be cancelled by pressing AF select button and ISO button at the same time.

If you use orientation dependent AF point selection, you'll have to register Home Points (HP) for all orientations.
When you set AF-ON and/or * to autofocus, you can press INFO to get deeper into the details, and there select with which point they should focus. You can also select if pressing the joystick should go to HP or not.

The registered point will be shown as a small dot in the viewfinder.

Last time I had good use for this was when shooting racing cars going in and out of a hairpin. For composition reasons, I didn't want to use the center AF point, but one a bit to the side. But the side changed when the cars changed direction in the hairpin. So by just selecting a point to the left and registering a point to the right, I could hold * when going into the hairpin and just changed to AF-ON when going out. A flick of the thumb while I tracked the car in the viewfinder.

Thanks! I can't wait to get my 7D (soon ) - I am going to have shutter 1/2 way as metering/AE Lock, AF-On btn as Metering/AF Start, and * btn as AF home button...

Cars going in and out of the hairpin I wrote about above.

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NPuter wrote in post #10889377
Thanks! I can't wait to get my 7D (soon ) - I am going to have shutter 1/2 way as metering/AE Lock, AF-On btn as Metering/AF Start, and * btn as AF home button...

If you use evaluative metering and One Shot AF, the shutter button half-press is AE lock by default.
Don't forget that if you don't always want AE lock on half-press, you have yet another button now, the M-Fn. When shooting action with automatic exposure, I ususally move AE lock to the M-Fn button. Thus it's there, but still allows me to follow and adjust exposure automatically accordingly, if needed. I'm often taking photos of people running between bushes and branches, in and out of sunlit areas, so the difference in illumination is often too much to handle smoothly in M mode. There's enough to think about regarding focusing and tracking. Tv allows me to keep the shutter speed I want for the motion effect, while I'm busy adjusting zoom, AF-ON, * and DOF buttons to control framing and focus point and mode selection.

The photo is one in a long sequence I shot when I evaluated the different AF settings for tracking runners that sometimes are hardly visible at all.

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apersson850 wrote in post #10889396
If you use evaluative metering and One Shot AF, the shutter button half-press is AE lock by default.
Don't forget that if you don't always want AE lock on half-press, you have yet another button now, the M-Fn. When shooting action with automatic exposure, I ususally move AE lock to the M-Fn button. Thus it's there, but still allows me to follow and adjust exposure automatically accordingly, if needed. I'm often taking photos of people running between bushes and branches, in and out of sunlit areas, so the difference in illumination is often too much to handle smoothly in M mode. There's enough to think about regarding focusing and tracking. Tv allows me to keep the shutter speed I want for the motion effect, while I'm busy adjusting zoom, AF-ON, * and DOF buttons to control framing and focus point and mode selection.

The photo is one in a long sequence I shot when I evaluated the different AF settings for tracking runners that sometimes are hardly visible at all.

Yep - I totally know what you are saying... On my T1i, I have always had * as focusing and shutter 1/2 press as AE lock - I actually like the shutter 1/2 press as AE lock for 90% of my shooting...

However, for action/tracking shooting, I plan on removing AE lock from the shutter button...

All combinations of AF and metering except evaluative and One Shot AF will allow you to make the decision about if you want AE lock or not.

In many cases, if you do need AE lock when shooting action, it may be easier to use M mode instead, and get locked exposure all the time.