7D2, 1Dx, 5D3 Owners- How to make AF system work better for you

digital paradise wrote in post #17278267
I put together a short primer because there are new features that are linked together that new users should know about and there is a lot of information to absorb. I’m not suggesting what anyone should use these settings. You should explore these further.

iTR – Intelligent Tracking and Recognition

It is new to the 7D2 and does affect AF area selection modes. See next section. The 1Dx has this feature as well. The 5D3 dos not have it.

ITR executes AF by recognizing faces and colors. This can be located on the AF4 (purple menus) screen and cab be enabled or disabled.

In AI Servo mode, the camera remembers the color at the position it is focused on first, then continues to track and focus the subject switching AF points to track that color.

In one-shot AF mode iTR basically looks for faces.

The manual states that when activated it will take longer to acquire focus. I’m not sure if a person could even tell as AF happens in milliseconds. It also states that if a face is too small in the frame it may have trouble finding it.

AF Area Selection Modes

1. First there the standard single point and spot focus point modes.

2. Followed by two expansion point modes to choose from.

- the first one enables 5 AF points

- the second one enables 9 AF points

NOTE: All above AF points are active at all times. They do not switch on and off while tracking.

3. The 3 zones.

- zone – enables 12 AF points.

- large zone – enables the entire centre or 2 outside clusters

- All 65 points

NOTE: All above AF points are not active at all times in the zone grouping and 65 point. They will switch on and off while tracking.

If iTR is enabled (on the AF4 menu screen) it will activate in "all 3" zones. So you may want to keep this in mind because if you go from expansion to zone, it not only activates iTR but the AF tracking characteristics change as well.

Awesome-- thanks for that

To supplement digital paradise's excellent post above, in any of the zone modes or with 65 point AF with auto-selection, the AF system will attempt to focus on the closest thing where any of the AF points is able to achieve focus. This can cause problems if there is something in the scene closer than the intended subject. There is also a menu selection available to specify which AF point will start AF in 65 point AF; it can be the point selected when changing to 65 point AF, or a pre-selected point that will always be the same, depending on which menu selection is made.

This won't open on my MAC. PC should work.

http://learn.usa.canon​.com …os7dmk2_afGuide​book.shtml

Just got the European PDF to open on my MAC.

http://www.brochures.c​anon-europe.com …ctid=9090&langu​ageid=-111

Here's a suggestion for keeping things simple, in terms of not having to switch back and forth from single shot to AI Servo. I typically kept my 7D in AI Servo and shot both static and moving subjects that way. This works great using back button focus, since with a static subject you can release the button once focus is achieved to lock focus, or with a moving subject keep the button pushed to keep the AF system active and tracking. I've been doing the same thing with my 7DII, and so far it seems to be working fine. I normally use single shot AF only when I need to use focus assist from a flash (which doesn't work in AI Servo).

stsva wrote in post #17278325
Here's a suggestion for keeping things simple, in terms of not having to switch back and forth from single shot to AI Servo. I typically kept my 7D in AI Servo and shot both static and moving subjects that way. This works great using back button focus, since with a static subject you can release the button once focus is achieved to lock focus, or with a moving subject keep the button pushed to keep the AF system active and tracking. I've been doing the same thing with my 7DII, and so far it seems to be working fine. I normally use single shot AF only when I need to use focus assist from a flash (which doesn't work in AI Servo).

Same here. I've been doing it that way since my 450D. Then 550D, 60D, 7D, and 5D3. Only use One Shot with with flash.

But now you can set back button focus, so that the AF-ON button and the * button activate two different AF modes/configs.

I have to AF-ON set to One-shot operations with 1 pt. AF
* button is set to Al Servo, Case 1, and Expand Surround for BIF

kesterc wrote in post #17278383
But now you can set back button focus, so that the AF-ON button and the * button activate two different AF modes/configs.

I have to AF-ON set to One-shot operations with 1 pt. AF
* button is set to Al Servo, Case 1, and Expand Surround for BIF

I've just never found One Shot necessary. I have mine set with AF-ON to AI Servo, Case 2. And * set to AI Servo, Case 3. One for BIF with background clutter, and the other for BIF in bare sky. Wish I could do that with my 5D3.

kesterc wrote in post #17278383
But now you can set back button focus, so that the AF-ON button and the * button activate two different AF modes/configs.

I have to AF-ON set to One-shot operations with 1 pt. AF
* button is set to Al Servo, Case 1, and Expand Surround for BIF

I changed the * button to switch instantly to 1/2000 shutter speed, spot focus, center small zone - basically switch to bird mode at a single press. I have a AF-On set to AF-Off so I can stop the focus drive while still using the half press on the shutter, I am just so used to the shutter button for a AF start I have no desire to change it..and it makes it almost impossible to hand the camera to someone else to use with BBF on.

Keyan wrote in post #17278435
I changed the * button to switch instantly to 1/2000 shutter speed, spot focus, center small zone - basically switch to bird mode at a single press. I have a AF-On set to AF-Off so I can stop the focus drive while still using the half press on the shutter, I am just so used to the shutter button for a AF start I have no desire to change it..and it makes it almost impossible to hand the camera to someone else to use with BBF on.

When handing the camera to someone else, just turn the mode dial to full auto.

kesterc wrote in post #17278383
But now you can set back button focus, so that the AF-ON button and the * button activate two different AF modes/configs.

I have to AF-ON set to One-shot operations with 1 pt. AF
* button is set to Al Servo, Case 1, and Expand Surround for BIF

I have AF-On set to Spot AF servo and * set to single point servo for Manual and Custom 1. Manual is set at 1/500 shutter and Case 3 and Custom 1 is at 1/1000 and Case 1. Custom 2 is Expanded Surround servo and Case 6 for BIF on the * and 65 points on AF-On. All are using Auto ISO. I have yet to decide what I am going to use for Custom 3.

A correction. I was looking at the on line manual and it has zone in different positions which can be either 12 or 15 AF points depending where that zone has been shifted to. I looked at that AF PDF I posted and when zone is in the centre, 15 points not 12 are activated. It is not a big deal but just for consistency I made the change to 15 AF points.

3. The 3 zones.

- zone – enables 15 AF points.

- large zone – enables the entire centre or 2 outside clusters

- All 65 points

7D Mark II, 1DX, 5D Mark III Owners- How to make AF system work better for you

digital paradise wrote in post #17278288
2nd release priority kicks in after the first shot has been taken. I find this one interesting. Once you lock on AI Servo is doing its job by tracking. If you are good at keeping that point on a bird or other moving objects then you don’ t have to waste system resources to continually re-check focus. If you set it to Speed then it will just continues to fire on focus lock you achieved in 1st image priority. If you select 10 FPS the system may not achieve it in Focus priority. Equal might be a good balance but the manual warns about shooting speeds slowing down using this setting.

You've misunderstood how AI Servo AF works.

First, One Shot AF is nromally better at acquiring focus than Servo AF. That's due to the time the camera spends doing each of the measurements with the AF sensor.
The 1DX camera is the first one to deviate from this, since it actually uses One Shot AF algorithms for part of the Servo AF service. These parts are those that aren't critical to maintaining the frame rate, like when tracking a subject with AF active but before the trigger button is pressed to start shooting. Thus everyone who claims Servo AF with the ability to turn it off with the AF-ON button is identical to using One Shot AF don't know what they are talking about. It may be good enough for your intended use, but identical, no.

When using Servo AF and taking the first image in a sequence, the camera will behave differently depending on the focus priority setting.
Release: The camera will make one single AF measurement and then drive the lens to whatever position it found from that measurement. If the measurement was correct everything is good. If it was not, the image will not be in focus.
Equal: If the single AF measurement fails, the camera will make a few more attempts (Canon doesn't tell exactly how many - it probably depends on the situation) before the shutter is released. As soon as one of these measurements gave a good result, the lens is focused and the shutter is released. If after some repeated attempts there still is no valid result, it will fire anyway and the image is out of focus.
Focus: The camera will make repeated attempts to measure focus, until it's successful. If never, then it won't fire either.

Now this same procedure continues when taking successive images. Rename release to speed, and you can follow the same explanation. What comes in as extra sugar on the cake here is when you enable more than one AF point. If you do, then the whole battery of algorithms used to try to figure out if the subject escaped from the main AF point and, if so, where it went, comes into play between each image. All the settings used to optimize this behavior are worthy a theseis by themselves, and that's why Canon wrote the AF setup guides.

I fixed the headline the way it should look on the first post, should this end up being a sticky.

kesterc wrote in post #17278383
But now you can set back button focus, so that the AF-ON button and the * button activate two different AF modes/configs.

I have to AF-ON set to One-shot operations with 1 pt. AF
* button is set to Al Servo, Case 1, and Expand Surround for BIF

That's one of the great things about this camera, you have a vast variety of ways to customize it so that it works exactly the way you want it.

apersson850 wrote in post #17278884
You've misunderstood how AI Servo AF works.

First, One Shot AF is nromally better at acquiring focus than Servo AF. That's due to the time the camera spends doing each of the measurements with the AF sensor.
The 1DX camera is the first one to deviate from this, since it actually uses One Shot AF algorithms for part of the Servo AF service. These parts are those that aren't critical to maintaining the frame rate, like when tracking a subject with AF active but before the trigger button is pressed to start shooting. Thus everyone who claims Servo AF with the ability to turn it off with the AF-ON button is identical to using One Shot AF don't know what they are talking about. It may be good enough for your intended use, but identical, no.

When using Servo AF and taking the first image in a sequence, the camera will behave differently depending on the focus priority setting.
Release: The camera will make one single AF measurement and then drive the lens to whatever position it found from that measurement. If the measurement was correct everything is good. If it was not, the image will not be in focus.
Equal: If the single AF measurement fails, the camera will make a few more attempts (Canon doesn't tell exactly how many - it probably depends on the situation) before the shutter is released. As soon as one of these measurements gave a good result, the lens is focused and the shutter is released. If after some repeated attempts there still is no valid result, it will fire anyway and the image is out of focus.
Focus: The camera will make repeated attempts to measure focus, until it's successful. If never, then it won't fire either.

Now this same procedure continues when taking successive images. Rename release to speed, and you can follow the same explanation. What comes in as extra sugar on the cake here is when you enable more than one AF point. If you do, then the whole battery of algorithms used to try to figure out if the subject escaped from the main AF point and, if so, where it went, comes into play between each image. All the settings used to optimize this behavior is worth a theseis by itself, and that's why Canon wrote the AF setup guides.

I fixed the headline the way it should look on the first post, should this end up being a sticky.

Very good info. - thanks!

I read and confirm that this is most likely correct that if you are having focus issues that you should slow down your focus case settings. I had sped mine up and focus accuracy was spotty. Since returning to the factory case settings all has improved. This may not work if your AF unit is faulty though.