EOS-1D X, Dual Back Button AF

[Steve Todd]

Having used the back button AF method for several years, I thought I would try the dual back button feature made possible by the recent 2.0.3 firmware update. Until the new firmware update, I separated the AF Start function from the Shutter Button using the normal back button method. My focusing method was to have the AF-ON button set for AI-Servo AF. If I wanted to quickly lock the focus, I would simply focus using AI-Servo AF, release my thumb from the button, reframe the subject and shoot. I could have just switched between the two modes by pressing the AF Drive button on the top deck and use the Main Dial to switch between One-Shot AF and AI Servo AF. However, that just wasen't quick enough for my shoot style.

Prior to the new firmware update, you could program one of the programable buttons to toggle between AI-Servo AF and One-Shot AF. However, that required me to press the button set to toggle between the two AF modes (I used the Multi-function 2 button), with my second finger (middle finger) while using my thumb to press the AF-ON button to focus and my index finger (pointing finger) to release the shutter. That's not good either. Sure, I could have also left the shutter button to the default setting (AF and Metering Start-Shutter Release), but I still like separating those functions.

With the new firmware update, you can now program the AF-ON button to AI-Servo and the AE lock button to One-Shot AF. Once set, they are then dedicated to perform those functions when pressed and held in regardless of what is set on the top LCD panel. Having used this now for a few weeks, I find it the perfect match for my style of shooting.

To program these functions, use page 343 of the updated EOS-1D X Manual (downloadable from the Canon USA website). Simply use Custon Function 5 (Operation, Custom Controls) To make the programming changes to the buttons.

BTW, I programed the MF2 button for Spot AF and the DOF button for AE Lock, as I rarely use the DOF button anyway. I also program the M-Fn button next to the shutter button for the Viewfinder electronic level function.

Using the two back buttons for instant AF selection and activation, together with the Shutter button only used for metering and shutter release, add a great new operational capability to the already wonderful camera. I just wish I could setup my 1D4 to do the same!

I realize this was a rather lengthy explanation, but I know I like it spelled out fully when someone suggests a new method to me! Hope this helps! It is definitely worth trying!

 

[9VIII]

Good post. Sounds nice.

Shooting birds (Magpies and Chickadees, you take what you get) in the bush this week I found myself changing between single shot and Servo a lot. If the bird is moving you want tracking, but if there's a bunch of twigs in the way you need it to stick with your subject and not hop around on all the things between you and it.
I almost wish there were two shutter buttons.

 

[StudentOfLight]

Great feedback. Happy there is added functionality with these firmware upgrades as opposed to only getting bug-fixes and sorting out compatibility issues.

 

[wickidwombat]

can the 5D3 do this?

 

[Viggo]

Just to add another tip in the same category.

I have used a similar setup since the 1dx came out. I haven't used the AE-button for One shot (obviously, but I have used the AE button for a "Case 6 scenario", Case 6, 4 point expansion, faster shutter, framrate etc, and the AF-ON button for Case 1 with single point etc. That way I cover both "normal" movement and stable tracking, but a slight move of my thumb sets the 1dX in "race-mode" ready for erratic craziness. I also use the M.fn button next to the shutter for Level, veryvery handy.

 

[mackguyver]

can the 5D3 do this?

Nope. Looking at the manual, I think you can set both buttons to start AF, but not to have one do AIServo and the other One-shot AF.

Viggo, I might have to give this a try, but I really don't use one shot AF. I just lock focus with AI Servo and release the back button. For the 50 & 85 f/1.2 lenses, this might help with accuracy for hand held portraits, so maybe I'll give that a try now that I am a proud new 1D X owner

 

[Viggo]

can the 5D3 do this?

Nope. Looking at the manual, I think you can set both buttons to start AF, but not to have one do AIServo and the other One-shot AF.

Viggo, I might have to give this a try, but I really don't use one shot AF. I just lock focus with AI Servo and release the back button. For the 50 & 85 f/1.2 lenses, this might help with accuracy for hand held portraits, so maybe I'll give that a try now that I am a proud new 1D X owner

I also not use One Shot at all. Tried it 4 times since I bought the 1d4 when it was new, lol.

 

[3kramd5]

can the 5D3 do this?

Nope. Looking at the manual, I think you can set both buttons to start AF, but not to have one do AIServo and the other One-shot AF.

Weird. Though that's a simple firmware thing they could add.

I am accustomed to using the DOF preview button to toggle one shot, but it would be nice for a tactile option (my thumb is here, therefore I am getting one shot) having to visually verify which mode I am in.

 

[mackguyver]

can the 5D3 do this?

Nope. Looking at the manual, I think you can set both buttons to start AF, but not to have one do AIServo and the other One-shot AF.

Weird. Though that's a simple firmware thing they could add.

I am accustomed to using the DOF preview button to toggle one shot, but it would be nice for a tactile option (my thumb is here, therefore I am getting one shot) having to visually verify which mode I am in.

LOL and I'm hoping they add at least some of these features to the 5DIII at some point via a firmware update.

Also, I swear I must be the only one that still uses the DOF preview button so doing that is a no go for me. I don't use the AE lock much, but would be reluctant to reassign it, too. Now I have the 1D X and I'm going to have to figure out what to assign to all of the numerous buttons!

 

[3kramd5]

I only tend to use DOF preview in live view (manual focus) since the VF isn't really faithful.

 

[sanj]

I do not understand. I have been using back button focus for a long while now and it seems fast enough. On the top lcd I leave it on servo focus.
What am I missing here? In any case I have the 1dx set exposure on the focus point.

Would love to understand this post, I constantly want to improve my technique.

 

[Northstar]

I do not understand. I have been using back button focus for a long while now and it seems fast enough. On the top lcd I leave it on servo focus.
What am I missing here? In any case I have the 1dx set exposure on the focus point.

Would love to understand this post, I constantly want to improve my technique.

Sanj...Steve is still using back button AF-on for servo...no change there.

The change is that he's now using the * button (AE lock) for when he wants to shoot in one shot mode.

 

[Viggo]

I do not understand. I have been using back button focus for a long while now and it seems fast enough. On the top lcd I leave it on servo focus.
What am I missing here? In any case I have the 1dx set exposure on the focus point.

Would love to understand this post, I constantly want to improve my technique.

Sanj...Steve is still using back button AF-on for servo...no change there.

The change is that he's now using the * button (AE lock) for when he wants to shoot in one shot mode.

If you never use One Shot, try my setup if you often wished you had a different AF-case, but try to make the best of what you already had selected. Or if the situation requires two AF scenarios.

 

[sanj]

Thanks for all the replies. The penny still fails to drop. It will one day, I hope. Currently either I do not know something or brain cells not working.
Perhaps soon I will have an 'ah ha' moment. Waiting.

 

[Viggo]

Thanks for all the replies. The penny still fails to drop. It will one day, I hope. Currently either I do not know something or brain cells not working.
Perhaps soon I will have an 'ah ha' moment. Waiting.

Think of it as having two light switches next to each other for one room, one light switch turns the room yellow (Ai Servo on AF-On button) and the other light switch turns the room blue (One Shot on the AE-Lock).

 

[Steve Todd]

Thanks Viggo for helping Sanj to understand how the method I described works through your great example! I'd hoped my original post had explained the process. However, I guess I could have done a better job of explaining it. That's what happens when you try to describe your thoughts on a technical subject...you know what you want to say, but your explanation doesn't adequately convey your thoughts to others. Thanks again! And happy shooting!

 

[Northstar]

Thanks for all the replies. The penny still fails to drop. It will one day, I hope. Currently either I do not know something or brain cells not working.
Perhaps soon I will have an 'ah ha' moment. Waiting.

sanj....you wrote "either i don't know something or"...could it be that you don't know that one shot is better(sharper)than servo for "non action" shots? I'm sure you know this but I just thought i would point it out just in case. (i'm sure you do know because i've seen your awesome images)

the main reason for wanting the set up steve describes is to quickly and more easily switch from servo to one shot by having the buttons right next to each other. ("af-on button" and "*" button) (servo and one shot)

 

[sanj]

Thanks for all the replies. The penny still fails to drop. It will one day, I hope. Currently either I do not know something or brain cells not working.
Perhaps soon I will have an 'ah ha' moment. Waiting.

sanj....your wrote "either i don't know something or"...could it be that you don't know that one shot is better(sharper)than servo for "non action" shots? I'm sure you know this but I just thought i would point it out just in case. (i'm sure you do know because i've seen your awesome images)

the main reason for wanting the set up steve describes is to quickly and more easily switch from servo to one shot by having the buttons right next to each other. ("af-on button" and "*" button) (servo and one shot)

Northstar: No I did not know that 'one shot' is sharper than servo for still objects. I thought is was about getting focus, not the way one got focus. And I believe that once I get focus and I remove the thumb from the back focus, I am as good as 'one shot'. Am I wrong?

Having said all of this, I am positive that I am missing something... I will get it one day and go 'yeyyyy'.

 

[Northstar]

Thanks for all the replies. The penny still fails to drop. It will one day, I hope. Currently either I do not know something or brain cells not working.
Perhaps soon I will have an 'ah ha' moment. Waiting.

sanj....your wrote "either i don't know something or"...could it be that you don't know that one shot is better(sharper)than servo for "non action" shots? I'm sure you know this but I just thought i would point it out just in case. (i'm sure you do know because i've seen your awesome images)

the main reason for wanting the set up steve describes is to quickly and more easily switch from servo to one shot by having the buttons right next to each other. ("af-on button" and "*" button) (servo and one shot)

Northstar: No I did not know that 'one shot' is sharper than servo for still objects. I thought is was about getting focus, not the way one got focus. And I believe that once I get focus and I remove the thumb from the back focus, I am as good as 'one shot'. Am I wrong?

Having said all of this, I am positive that I am missing something... I will get it one day and go 'yeyyyy'.

Hi Sanj...I believe the "predictive" nature of AF servo leads to a lower hit rate on critically sharp images vs one shot...at least that's been my experience.

Even if you acquire focus with servo and release the AF-on button like you wrote, the focus was acquired using the predictive algorithms that servo uses. The servo system works great most of the time, but if something truly isn't moving, it's better to not have the predictive nature of servo involved.

If I'm wrong about this then someone please tell me.

North

 

[Loswr]

Thanks for all the replies. The penny still fails to drop. It will one day, I hope. Currently either I do not know something or brain cells not working.
Perhaps soon I will have an 'ah ha' moment. Waiting.

sanj....your wrote "either i don't know something or"...could it be that you don't know that one shot is better(sharper)than servo for "non action" shots? I'm sure you know this but I just thought i would point it out just in case. (i'm sure you do know because i've seen your awesome images)

the main reason for wanting the set up steve describes is to quickly and more easily switch from servo to one shot by having the buttons right next to each other. ("af-on button" and "*" button) (servo and one shot)

Northstar: No I did not know that 'one shot' is sharper than servo for still objects. I thought is was about getting focus, not the way one got focus. And I believe that once I get focus and I remove the thumb from the back focus, I am as good as 'one shot'. Am I wrong?

Having said all of this, I am positive that I am missing something... I will get it one day and go 'yeyyyy'.

There was another thread about using AI servo and back button AF instead of one shot. The theoretical issue I have with that method is that even with fast lenses, AI servo uses data from the less accurate f/5.6 sensor lines because they are faster. Practically, I don't know how much difference that actually makes in real world shooting.

As Northstar points out, the algorithm is different as well, AI servo is optimized for moving subjects.