What settings do I use to back button focus set up for the d5 mark 3? TIA

[TinkersRealm]

5D Mark 3

[7D5D]

Lots of basic video tutorials here, one is how to separate focus from the shutter button, I'm assuming that is what you are asking.
http://learn.usa.canon.com/galleries/galleries/tutorials/eos_5d_markiii_tutorials.shtml

[TinkersRealm]

Yes, I have watched them but it seems like there are about 10 different options so I was hoping someone would just have the basic select custom # 1 or custom 5 & 6 or something very specific LOL!  

I am switiching over from Nikon to Canon and so am in a small learning curve. 

[TCampbell · Accepted solution]

When you activate the menu, scroll over (using the dial on the front of the camera) to the orange "C.Fn2: Disp./Operation" menu. (that's the icon of a camera that has a index marks for a light meter below it -- right of the wrench icon, left of the star icon.)

Each of those menu's on the 5D III have multiple pages.  It's the 2nd page (the 2nd dot from the left) that has the category for "Custom Controls".  Highlight that (using the dial on the back this time) and click the 'set' button.

That brings up a menu showing each of the major controls on the back of the camera and what they do.  Highlight the icon for the shutter button (this only changes the behavior of a half-press) and change it from "Metering and AF start" to just "Metering start".

The "AF-ON" button (on the back of your camera) is likely already set to "Metering and AF start" (I believe that's the factory default.)  

So you're not so much enable back-button focus (which is already probably active)... you're more "disabling" the focus when  the shutter button is pressed half-way.

Good luck

[TinkersRealm]

Thank you so much Tim/TCambell &  Amfoto-That is exactly what I needed to know-Where to go in the menu & which option to select.  Your Answers saved me so much time & fumbling around for days w/the options 😉  I am Grateful!  

I have made the changes & am ready to shoot! 😉

Thank you so much for taking the time to detail the steps out for me-Your Awesome!!!!

[amfoto1]

Acually, on all the recent cameras with an AF On button, you already have Back Button Focusing capability, by default.

However, to use BBF most fully, you have to unassign it from the shutter release button. On 5DIII that's done by going into the menu, navigating to Custom Controls (the last item under camera setup/custom function tab 2, see page 321 of your manual). Then select the shutter release button and set it to the second  or middle option, labelled "Metering Start", then press "Set" button. This will remove AF function from your shutter release button and leave it only on the AF On button on the back of the camera (also on the vertical grip).

Alternatively, in the same area of the menu you can swap the function of the AF On button and the * (AE Lock) button. I always do this for several reasons. First, the * button is larger, protrudes more, is closer and just falls more naturally under my thumb. I focus every shot, but only occasionally use AE Lock. So it makes more sense to me to have the * button operate focus, and the AF On button do AE Lock. Another reason I do this is because I've been using BBF for many years (since EOS-3. A2E & Elan 7E), and it wasn't until 40D that Canon put an AF On button on the camera (there wasn't an AF On button on vertical/battery grip either, all the way through the 50D).... we had to use the * button for BBF. So I'm kind of in the habit of using it still.

EDIT: Hah! What Tim said! Great minds think alike.