EF 100-400mm f/4.5-5.6L IS II USM Autofocus suddenly not working

[canonbirds]

Had this lens since Sep 2019 and worked beautifully for about 6-7 months and I've started noticing issues with it's AF for a couple months. 

I mainly shoot birds, f/5.6 to f/8. IS mode set to 2 on the lens for movement. AI Servo on the camera body. Av mode on the camera body so it chooses the shutter speed, I only change the f-stop sometimes and possibly the ISO but not much (maybe 2-400). Like I said, it worked great for months and months had no issues.

Now with everything being exactly the same and still using multiple point AF it will not consistently focus on the bird I'm aiming directly at and clearly have in my sights. Press the shutter halfway down, you can hear the motors in the lens trying to work and it just doesn't focus on the subject anymore. Every now and then I might get lucky based on proximity.

I called Canon today and was on the phone 20 minutes explaining the issue. He said I would receive Emails with directions on mailing the lens to them. He repeated my Email address back to me perfectly and I have not received any notifications.

Should I clean the lens without the caps off in any way? Should I do anything before sending it or taking it to repair? Any help anyone can provide is much appreciated. I've taken great care of it and I kind of expect a $2k piece of equipment to work properly. 

[wq9nsc]

The Depth of Field preview button steps the lens aperture down to the setting that will be used when actually taken the photo, otherwise the lens is left wide open for the brightest viewfinder display and best AF performance.  When you pressed the button and the display dimmed it shows that the aperture in the lens is behaving normally. 

The DoF preview button is a handy feature to use when you are trying to make sure that everything you want is in focus  (from front to back).  As the aperture is closed down, the depth of field increases and although the view grows darker in the viewfinder, you will be able to see what will and will not be in focus in the actual image.

How many AF points are you allowing the camera to use to achieve focus?  With telephoto lens, both for sports and for wildlife, I most commonly restrict AF to a single point and sometimes a single point with expansion.  Any chance you changed the AF point selection and that is causing the AF to now behave differently for you as it decides which AF points to use?  For birds in flight, you probably want to use a single point with expansion but for a perched bird I would try using a single AF point to see how that works for you.  The widest aperture with the 100-400 isn't fast enough to actuate the dual cross type sensors which provide the fastest and most accurate AF but that hasn't changed since you purchased the lens so that isn't the reason for a change in its focus performance.

Rodger

[canonbirds]

I use single point expansion where there is 4 around it like a cross. I've previously used more and didn't like the obstructed view or the results. I've also previously used just single point but that just doesn't work very well when I'm trying to capture small songbirds.

I've used this for a while so I think it could be something in the camera settings I've changed and just forgotten about. Possibly something in the AF menu or the menu where there are 6 options with the tracking features.

Thanks for the replies Rodger

[ebiggs1]

"I've also previously used just single point but that just doesn't work very well when I'm trying to capture small songbirds."

Yes, yes it does and it is what you need to use. If you have a small bird and have other AF points available the lens may focus on a closer object (that's normal) and not the bird. Keep just the center point active, shut all the others off.

Here is what we should do.  First reset the camera, BTW, what camera are we using? Anyway reset it to factory. (Menus, tools, clear all settings and clear all custom settings)  Now set it to P mode, ISO 200, average WB.  Select to use just the center AF point. Do not mess with or set any other setting, only those I recommended.  Now make sure the lens is set to AF, full range and IS on. Double check.

Now go outside on a nice day and take random shots, Go to a park or some place nice. Don't shoot any birds just stuff, anything. If your camera/lens makes good shots, nice focus, exposure, there is nothing wrong with it or the lens.

[Waddizzle]

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@canonbirds wrote:

I use single point expansion where there is 4 around it like a cross. I've previously used more and didn't like the obstructed view or the results. I've also previously used just single point but that just doesn't work very well when I'm trying to capture small songbirds.

I've used this for a while so I think it could be something in the camera settings I've changed and just forgotten about. Possibly something in the AF menu or the menu where there are 6 options with the tracking features.

Thanks for the replies Rodger

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Exactly, losing track of setting changes is one reason why I have saved custom shooting modes for action and wildlife photography.  I have disabled the automatic update to the custom shooting mode settings.  You might consider this for your 7D2

I call C1 "bird on a branch" mode.  It uses just the center AF point, One Shot AF mode, Single Shot drive mode, and back button focus.  I use center weighted metering, too.  Pick your favorite shooting mode.  

I call C2 'action photography" mode.  It uses the center AF point as the starting point for tracking.  It uses AI Servo AF mode, Continuous drive mode.  I use the BBF button for [AF-OFF], though, instead of the more typical [AF-ON].  I use evaluative metering, but I may change it to center weighted average.

If you are only using the center AF point, or just the center and its' assist points, then the AF Case settings are moot and become totally meaningless.  The case settings only apply to AF tracking in Zone AF or with all AF points enabled.  If you are only using the center AF point, then you the photographer are doing 100% of the AF tracking, not the camera.

[EDIT]. One benefit of saving these custom shooting modes is that a standard camera reset does not clear them out.

[canonbirds]

I may try that at some point with the custom settings. I didn't realize the tracking menu was meaningless if you weren't using all 65 points, I guess that makes sense. 

I still feel like it may be a camera setting I changed at some point and just forgot because I have months and months of being out in the field with great, sharp pictures using AF expansion (4-point cross shape) on small birds, large birds, medium-sized birds, birds in flight, you name it, I've got it. 

It's a setting that's preventing me from autofocusing and I don't know what that is, or it's the lens. 

Thanks for the replies

[Waddizzle]

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@canonbirds wrote:

I may try that at some point with the custom settings. I didn't realize the tracking menu was meaningless if you weren't using all 65 points, I guess that makes sense. 

I still feel like it may be a camera setting I changed at some point and just forgot because I have months and months of being out in the field with great, sharp pictures using AF expansion (4-point cross shape) on small birds, large birds, medium-sized birds, birds in flight, you name it, I've got it. 

It's a setting that's preventing me from autofocusing and I don't know what that is, or it's the lens. 

Thanks for the replies

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Follow Ernie's advice to reset the camera.  Some setting have their own reset.  The AF Case settings, Custom Shooting Modes, Custom Controls, and a couple of other topics have their own separate reset.

Speaking of Custom Controls, press the [AF-ON] button, just in case you set up BBF and have forgotten about. It.

[wq9nsc]

The 7D Mark II may be different from the 1DX and 1DX II  where AF cases 1 through 4 are also applicable to single point AF with only 5 and 6 not applicable to a single AF point.  The 1DX III is a little different with only 4 cases but a lot more is done by the camera.  So check the AF guide for the 7D II to ascertain exactly what is happening/being modified as you step through the cases and whether you accidentally modified the settings for the case you are using.  To get around all of this I would first test AF in one shot mode so that AI servo and the various cases/modifications don't come into play.

Another option that is probably in the 7D II is how priority is biased for the first shot and then for subsequent shots in a burst mode where you can bias towards shutter release over focus or focus over shutter release.  If it is biased towards focus, it could increase lag before the shutter releases but it would NOT slow actual focus speed.  But if you go with shutter release priority, then it does increase the likelihood of getting more out of focus shots.

Rodger

[canonbirds]

I'll have to make some notes on what my settings are currently before I jump straight into a factory reset. Then I'll do it and go snap some shots

Thanks for everyone's replies

[ebiggs1]

"I'll have to make some notes on what my settings are currently ..."

There is little reason to do that.  They are wrong.  Most of the time the camera knows what to do.  People get into trouble when they tell it to do differently.  Don't try to over think a simple task.  Please do the reset and test.  If nothing else it will assure you that the camera/lens is working as it should.

[canonbirds]

I appreciate you responding and trying to help, truly I do. The custom settings is not something I'm going to do now, I'm well aware that was advice he was giving me to try out in the future. I guess I have come across as slow or ignorant so I apologize for not communicating clearly but your last messages are somewhat patronizing. 

It's not an exercise in futility to jot down current camera settings if I'm going to reset the camera; there are settings that have nothing to do with the lens autofocus that I may forget if I don't write them down. I just did it, it took about 15 minutes, and it gave me needed perspective. I can still reset the camera settings, what harm did that do?