5D3 AI Servo faulty?

Ok guys, I just tested out my 7D with my 70-200 f2.8 (previously only been using 135 f2) and this issue seems AI Servo specific. SLK Photo, did you notice this too or does your issue occur in one shot? It seems like a body problem, not a lens problem. Mine occurs in AI Servo only though, one shot and live view AF is spot on. I've tried everything - use one AF point, use certain AF points, use more AF points, changed settings.

I know my 7D well enough (been with it for almost 3 years), and having used older Canon EOS digital models, to know that this behavior isn't normal and that this isn't a settings issue (at least on the surface). And I've already done a 'reboot' by taking out the main and watch batteries, and the issue still occurs.

A lot of folks seem to blame the AF points but my experience shooting runways for a couple of years and then switching to sports (both dealing with moving subjects) is that Canon's SLRs from the DIGIC 1 and DIGIC 2 days have already been intelligent enough to not be easily fooled (although it can happen, but very occasionally versus every other shot in this situation) by nearby objects and such.

Even when subjects have moved off the area covered by AF point(s), there's always been a split second allowance 'lag' that focus remains intact for the 0.5-1 second a subject moves off from AF points (seems the logic behind this is in case the subject comes back in), before the camera decides "ok the subject isn't coming back, readjusting focus).

It's safe to assume that something that you can't repair yourself has gone wrong and you should send in your 5D3 for a checkup (that's what I'm going to do with my 7D)

I'm going to contact Canon on Monday to arrange for my 7D to be sent in. However I haven't dealt with Canon USA service before. Do I call or email them explaining my situation? Do I have to pay for shipping there and/or back? How long does service typically take?

I have used AI Servo a lot on my previous 30D and a little less on my current 5DII.

I've found that it is vital to keep my chosen AF point (usually the centre but not always) glued to my chosen focus point, any wandering off and A I Servo picks my new focus point! So its vital to learn the trick of staying exactly on the chosen focus. Of course it needs to have a contrast so that the AF can pick it up, that goes without saying.

Wandering from the exact focus and coming back just serves to confuse the system and needs to be avoided.

EOS Man wrote in post #15059882
Ok guys, I just tested out my 7D with my 70-200 f2.8 (previously only been using 135 f2) and this issue seems AI Servo specific. SLK Photo, did you notice this too or does your issue occur in one shot? It seems like a body problem, not a lens problem. Mine occurs in AI Servo only though, one shot and live view AF is spot on. I've tried everything - use one AF point, use certain AF points, use more AF points, changed settings.

I know my 7D well enough (been with it for almost 3 years), and having used older Canon EOS digital models, to know that this behavior isn't normal and that this isn't a settings issue (at least on the surface). And I've already done a 'reboot' by taking out the main and watch batteries, and the issue still occurs.

A lot of folks seem to blame the AF points but my experience shooting runways for a couple of years and then switching to sports (both dealing with moving subjects) is that Canon's SLRs from the DIGIC 1 and DIGIC 2 days have already been intelligent enough to not be easily fooled (although it can happen, but very occasionally versus every other shot in this situation) by nearby objects and such.

Even when subjects have moved off the area covered by AF point(s), there's always been a split second allowance 'lag' that focus remains intact for the 0.5-1 second a subject moves off from AF points (seems the logic behind this is in case the subject comes back in), before the camera decides "ok the subject isn't coming back, readjusting focus).

It's safe to assume that something that you can't repair yourself has gone wrong and you should send in your 5D3 for a checkup (that's what I'm going to do with my 7D)

I'm going to contact Canon on Monday to arrange for my 7D to be sent in. However I haven't dealt with Canon USA service before. Do I call or email them explaining my situation? Do I have to pay for shipping there and/or back? How long does service typically take?

I think we are pretty much in the same boat. My unit is fine in one shot and live view and it is actually fine in every AI servo selection mode except when all focus points are selected. I did a test yesterday with some birds comparing the 5D3 and the 7D. My keeper rate with the 7D was about 95% while with the 5D3 it dropped to about 25% regardless of how I configured the AF. I simply can't believe that after 20 years of pursuing photography and using Canon exclusively since I went digital that I somehow lack the ability to get a keeper rate on the 5D3 that approaches or exceeds what I can get with the 7D, particularly after so much fiddling and testing.

Your point about the lag in regaining focus when a subject moves out of the covered AF area is interesting. In the case of the 5D3 this can be adjusted to a degree in that the camera can be configured to focus quickly on a new subject that may appear between the camera and what you are tracking or ignore it. In my case with all points selected this remains theory as I can't put it into practice. For example, there is a pre-programmed scenario to instantly focus on subjects suddenly entering the AF zone. So one would assume with this scenario if you were tracking something that went outside the AF zone it would be picked up again when it came back in if it met the normal criteria for being picked up by the AF. This doesn't work for me. If the dog or bird goes outside the AF area I'll never get it picked up again even when, in the case of the dog, he stays in the centre of the frame for several seconds and takes up all or most of the AF area.

I'll probably get the camera off to Canon this week so I'll let you know how it develops.

Lowner wrote in post #15060584
I have used AI Servo a lot on my previous 30D and a little less on my current 5DII.

I've found that it is vital to keep my chosen AF point (usually the centre but not always) glued to my chosen focus point, any wandering off and A I Servo picks my new focus point! So its vital to learn the trick of staying exactly on the chosen focus. Of course it needs to have a contrast so that the AF can pick it up, that goes without saying.

Wandering from the exact focus and coming back just serves to confuse the system and needs to be avoided.

Agreed but if I understand what you are saying I think you may mean the camera picks up a new focus subject and not a new focus point. This is based on the fact that you seem to be saying that you use one fixed focus point and in that case this would be a normal and expected behaviour on the part of the camera. If you are restricting the camera to one focus point then that point will focus on whatever it is pointed at. Lose your subject, lose your focus. In the case of using all points, you pick the subject up on your selected point and when the subject moves within the AF zone the camera tracks it from AF point to AF point. In the case of the 5D3 it does so based on settings that are nicely configurable by the user. This is not only useful but vital when tracking subject like birds in fight that are impossible to keep on one selected focus point.

SLKPhoto wrote in post #15060930
Agreed but if I understand what you are saying I think you may mean the camera picks up a new focus subject and not a new focus point. This is based on the fact that you seem to be saying that you use one fixed focus point and in that case this would be a normal and expected behaviour on the part of the camera. If you are restricting the camera to one focus point then that point will focus on whatever it is pointed at. Lose your subject, lose your focus. In the case of using all points, you pick the subject up on your selected point and when the subject moves within the AF zone the camera tracks it from AF point to AF point. In the case of the 5D3 it does so based on settings that are nicely configurable by the user. This is not only useful but vital when tracking subject like birds in fight that are impossible to keep on one selected focus point.

Exactly. I've had no success with the assist points on the few occasions I have tried them, so have taught myself to be VERY precise with focusing. Its not impossible, it just needs a lot of practise.

Interesting to hear this. Mine does the same thing. AI Sirvo works poorly or not at all. I actually had better success with my 5D and 5D2. It will miss focus on some one walking at a normal pace, even though when I review the picture it shows the red square right on target.

Lowner wrote in post #15063863
Exactly. I've had no success with the assist points on the few occasions I have tried them, so have taught myself to be VERY precise with focusing. Its not impossible, it just needs a lot of practise.

I find this a bit depressing, as I hear it time and time again, especially as I thought the 5DIII (my eventulal dream Camera) was the solution to Canon's poor AF system.

Submariner wrote in post #15064023
I find this a bit depressing, as I hear it time and time again, especially as I thought the 5DIII (my eventulal dream Camera) was the solution to Canon's poor AF system.

Not sure why it should be depressing. Non of us are born with the skills we need in our path through life, they come from leaning and practise. Thats good news, because it means there is hope for us all.

Using all focus points (61 of them as I recall) in AI Servo mode is asking for trouble.

EOS Man wrote in post #15059882
I'm going to contact Canon on Monday to arrange for my 7D to be sent in. However I haven't dealt with Canon USA service before. Do I call or email them explaining my situation? Do I have to pay for shipping there and/or back? How long does service typically take?

Go here: http://www.usa.canon.c​om …/eos_7d#Service​AndSupport
Look under "Service and Repair> Arrange a Repair"
All of my experience has been warranty work and I pay to ship it to them and they pay for return shipping, but that may be different since yours is obviously out of warranty. Time it takes is usually 1-2 weeks.

John from PA wrote in post #15064094
Using all focus points (61 of them as I recall) in AI Servo mode is asking for trouble.

I'm sorry but I disagree. Under proper conditions using all points can be the best, if not the only method to capture your subject. I have taken thousands upon thousands of shots using all points on BIFs. As I keep this configuration as one of my custom user settings I end up using it ad hoc on a lot of subjects and a good number of those shots could not have been tracked using another selection mode as well. Even if using all 61 points is trouble as you say I fail to see why it would be trouble to the tune of an average keeper rate that is anywhere between 50% - 75% less than on a camera with an AF system that is supposedly less capable than the 5D3.

My experience agrees with John from PA, The more AF points the more confusion the camera gets into. If the AF points were side by side with no gaps between them, then maybe it might be possible, but each gap the subject falls into forces the camera to hunt for focus and the more AF points "on duty", the more chance of it selecting a different high contrast point that has absolutely nothing whatever to do with the subject.

Lowner wrote in post #15070534
My experience agrees with John from PA, The more AF points the more confusion the camera gets into. If the AF points were side by side with no gaps between them, then maybe it might be possible, but each gap the subject falls into forces the camera to hunt for focus and the more AF points "on duty", the more chance of it selecting a different high contrast point that has absolutely nothing whatever to do with the subject.

I understand what you are saying but the question really isn't whether more focus points can confuse an AF system. I think most will agree that is in fact the case. The question here really is are there units out there with a compromised AI Servo focusing system?

Just to reiterate my original concern I'm at a loss to explain why I have a keeper rate so much lower on the 5D3 compared to the 7D. One would assume that my keeper rate should be reasonably close to the 7D despite the learning curve and the fact that the 5D3 is more configurable and therefore more prone to be configured in a way that complicates focus. Once again, I'm not a nob and I've worked every possible scenario thoroughly. More to the point I can focus my 5D3 at a telephone poll against a clear blue sky and by panning the camera within the AF zone - even very slowly - I can make the AF lose focus. Then even in the case of AF config tool scenario 3 (focus in subjects suddenly entering the AF zone) I often can't get the camera to re-focus by panning away from/return to subject or even keeping the camera on subject. I usually have to resort to releasing AI servo completely, re-aquire the subject with my selected point are engage focus again. Of course it won't be long before I lose focus again. So in summary I agree that 61 points will not be as good as 1 point or zone, etc. but if an AF system cannot deal with the scenario I just described there is definitely a problem. I think everyone can agree on that - 61 point lovers or not.

Panning on a stationary object is bound to fail and proves nothing, the whole point of panning is to keep that AF point nailed.

Your solution to reaquire the subject is what we surely all do in the same situation. Everything you describe fits normal operation, I'm still not convinced its a camera problem.

Lowner wrote in post #15073371
Panning on a stationary object is bound to fail and proves nothing, the whole point of panning is to keep that AF point nailed.

Your solution to reaquire the subject is what we surely all do in the same situation. Everything you describe fits normal operation, I'm still not convinced its a camera problem.

That panning is meant to simulate a fast moving subject shifting across the 61-point field due to operator's inability to keep it steady on the same AF point.

The test makes sense to me (undemanding actually, compared to BIF) and according to a Canon tutorial it should work, but I it doesn't for me either. To be honest, I didn't expect miracles from this technique and I am surprised that it works well enough for the OP on their 7D (which I don't have).