Nikon Focus Issue - D4s, 70-200 f2.8

[Belly]

Hi all,

My D4s with the 70-200f2.8 has intermittently just started to have auto focus issues. The lens is 3 years old and performed flawlessly. The camera about 1 year old and also been a stellar performer.

The problem arises when in continuous focus mode (eg tracking a moving object). It starts to play up after this focus mode has been worked hard. Then, no matter what I do (remove battery, remove lens and put it back on again, try other focus modes etc) the big rig refuses to focus. I can manually focus the lens, no problems. Pull it out the next day and all is fine?!?!?! that is until I start using continuous focus mode hard again - very frustrating!

I will be trying (when it arrives) a good clean of the CPU contacts using Camera Check Points "DeoxIT"

I have the latest Firmware updates.

Is this a lens or camera issue - or both???

I would be very interested to know if anyone else has experienced this and what they did about it.

Thanks in advance...

Belly

[Lance B]

Does it happen with any other lenses under the same operating conditions? If not, then I suspect a lens issue. Send lens to Nikon for service.

[arthurking83]

I suppose some deductive reasoning may assist with the answer.

Simple question: do any of your other AF-S lenses do similar things.

As AF-S lenses use their own motor, the two most likely culprits for causing such an issue are:

1/ the lens itself .. a possible warning that the SWM motor in the lens is on it's way out. (they can die)
2/ As the lens takes instructions from the camera on when to focus, maybe (as you already indicated) cleaning the contacts will help.
But if you think about it in a logical manner, if the contacts from camera to lens(for both AF signal and power) were dodgy in any way, you'd more likely get randomly occurring focus issues, rather than that you described where durability is the issue.

Think of it in a similar vein to your car engine overheating. If you place a load on it, it starts to heat up and it will either stop, or you have too.

As for cleaning contacts, both lens and cameras .. I use a clean pencil eraser. Lightly rub thee contacts of both devices.
I've had some issues with some lenses and it's worked well when they played up... always the lens side of things.

So, as your first point of attention .. you really should be testing a similar focus regime with any other AF-S type lens .. if you have one.
If you only have AF-D(or AF) type lenses ... ie. screw driven types .. don't bother. It may reveal no significant result, or may produce a misleading result.
The screw driven lenses use similar but still different enough focusing systems to make this an important point of difference.
Even if the lens is a HSM(Sigma) or USD(Tamron) type lens(or any other that relies purely on an electronic connection between camera and lens for focus.

So if you do test any other lenses and they're operating fine, then obviously the 70-200 is the issue(I reckon most likely the cause).
If any other electronically driven lens is having the same or similar issues, then obviously it's the camera that's the problem.

For your sake, pray it's the former and not the latter .. except if it's just a contact (on the body) cleaning issue on the camera.

FWIW: My only two issues with respect to camera lens communication have been:
1/ my D300 and Sigma 10-20mm lens(HSM). Camera simply wouldn't recognise it one day (totally out of the blue).
Mounted unmounted remounted the lens and still naught. This was while I was out and about, so of course the lens had to be removed and another lens was mounted for the rest of that trip.
On the way home on that trip whilst I was just driving, it suddenly occurred to me .. AH! the contacts!
Soon as I got home I cleaned the contacts on the lens, after first confirming that it was still a problem and ...
(that lens is still going strong 7 years later)
and
2/ The other issue was the Nikon 18-105VR kit lens. A total focus failure. Once again didn't initially think the contacts would be the issue, my immediate reaction was a failed focus motor on the lens.
This one was still fairly new .. less than a year old. I think it's natural to assume the worst in such a situation.
This was at home, and after a very quick partial dissassembly of the rear mount .. again the thought came to me that it may have just been a contact issue. Put it together, cleaned the lens contacts .. and again.
Both times I just used a decent quality soft-ish pencil eraser on the lens contacts .. just lightly .. and all good.

Hope it all works out for 'ya.

[Belly]

Does it happen with any other lenses under the same operating conditions? If not, then I suspect a lens issue. Send lens to Nikon for service.

Thanks Lance, both times this has happened I have not been in a situation where I can immediately change the lens for another. So this weekend I have time set aside to orchestrate a mock up and be ready when it does happen.

cheers
Belly

- - - Updated - - -

I suppose some deductive reasoning may assist with the answer.

Simple question: do any of your other AF-S lenses do similar things.

As AF-S lenses use their own motor, the two most likely culprits for causing such an issue are:

1/ the lens itself .. a possible warning that the SWM motor in the lens is on it's way out. (they can die)
2/ As the lens takes instructions from the camera on when to focus, maybe (as you already indicated) cleaning the contacts will help.
But if you think about it in a logical manner, if the contacts from camera to lens(for both AF signal and power) were dodgy in any way, you'd more likely get randomly occurring focus issues, rather than that you described where durability is the issue.

Think of it in a similar vein to your car engine overheating. If you place a load on it, it starts to heat up and it will either stop, or you have too.

As for cleaning contacts, both lens and cameras .. I use a clean pencil eraser. Lightly rub thee contacts of both devices.
I've had some issues with some lenses and it's worked well when they played up... always the lens side of things.

So, as your first point of attention .. you really should be testing a similar focus regime with any other AF-S type lens .. if you have one.
If you only have AF-D(or AF) type lenses ... ie. screw driven types .. don't bother. It may reveal no significant result, or may produce a misleading result.
The screw driven lenses use similar but still different enough focusing systems to make this an important point of difference.
Even if the lens is a HSM(Sigma) or USD(Tamron) type lens(or any other that relies purely on an electronic connection between camera and lens for focus.

So if you do test any other lenses and they're operating fine, then obviously the 70-200 is the issue(I reckon most likely the cause).
If any other electronically driven lens is having the same or similar issues, then obviously it's the camera that's the problem.

For your sake, pray it's the former and not the latter .. except if it's just a contact (on the body) cleaning issue on the camera.

FWIW: My only two issues with respect to camera lens communication have been:
1/ my D300 and Sigma 10-20mm lens(HSM). Camera simply wouldn't recognise it one day (totally out of the blue).
Mounted unmounted remounted the lens and still naught. This was while I was out and about, so of course the lens had to be removed and another lens was mounted for the rest of that trip.
On the way home on that trip whilst I was just driving, it suddenly occurred to me .. AH! the contacts!
Soon as I got home I cleaned the contacts on the lens, after first confirming that it was still a problem and ...
(that lens is still going strong 7 years later)
and
2/ The other issue was the Nikon 18-105VR kit lens. A total focus failure. Once again didn't initially think the contacts would be the issue, my immediate reaction was a failed focus motor on the lens.
This one was still fairly new .. less than a year old. I think it's natural to assume the worst in such a situation.
This was at home, and after a very quick partial dissassembly of the rear mount .. again the thought came to me that it may have just been a contact issue. Put it together, cleaned the lens contacts .. and again.
Both times I just used a decent quality soft-ish pencil eraser on the lens contacts .. just lightly .. and all good.

Hope it all works out for 'ya.

Hi Arthur and thanks for your reply. As mentioned to Lance I unfortunately have not been in a situation where I could apply deductive reasoning and swap to another lens, of which are all AF-S type. That will change this weekend however!!
I feel mildly confident after reading your real life examples and solved by a simple clean with an eraser. My CPU cleaning kit has arrived (eraser as well) so hopefully this is a simple and cheap fix! Either way I will let you all know. Thanks again.

Belly

[fillum]

Don't know if this will be of much help Belly...

I have the older version of the lens. I have a problem that when the lens is hunting for focus and it moves to the closest focus point, it 'jams' and stops focusing. Even turning the focus ring on the lens has no affect. I have now set the distance-limit-switch (or whatever it's called) to the 2.5m(?)-to-infinity setting so that the lens now doesn't move to the minimum focus setting and it works fine in that range - I typically don't use it for shooting anything close. (So yep it's on an ever-expanding list of things that need to go back to the workshop for some remedial attention). I can't remember how I 'unjammed' it - just 'fiddling about' I think.

Hope your problem is not too serious...

[Belly]

Don't know if this will be of much help Belly...

I have the older version of the lens. I have a problem that when the lens is hunting for focus and it moves to the closest focus point, it 'jams' and stops focusing. Even turning the focus ring on the lens has no affect. I have now set the distance-limit-switch (or whatever it's called) to the 2.5m(?)-to-infinity setting so that the lens now doesn't move to the minimum focus setting and it works fine in that range - I typically don't use it for shooting anything close. (So yep it's on an ever-expanding list of things that need to go back to the workshop for some remedial attention). I can't remember how I 'unjammed' it - just 'fiddling about' I think.

Hope your problem is not too serious...

Hey thanks Phil, appreciate your feed back mate. I remember trying the manual focus ring when the problem occurred and no issues there. I'm really hoping for a quick fix.

cheers
Belly

[mongo]

Auther has given so good ideas. Mongo would be very careful using the eraser on the camera body in case you get little bits of eraser coming off inside the camera.

Mongo has not had this issue but will try it out on his idential equipment this weekend to see if he gets the same results after working the continous AF hard. Will let you know.

However, Mongo's best guess would be that it is more likely a lens issue. If it works OK again after some time, the AF motor may be getting too warm and only returns to normal after cooling down ??


Again, will let you know.

[arthurking83]

.... Mongo would be very careful using the eraser on the camera body in case you get little bits of eraser coming off inside the camera. .... [/QUOTE]

This thought had occurred to me too, but you do it so lightly that bits of rubber shouldn't be an issue.
The idea is that you don't so much erase any miscreant particles on the contacts .. you just lightly rub the eraser to see if it helps in any way. Just a slight removal of any non conductive material on the contacts is enough to indicate if this is the problem.
If it is and it works, you then clean the contacts properly(I've used Eclipse fluid), or .. if the problem doesn't reappear again, just leave it.

...... If it works OK again after some time, the AF motor may be getting too warm and only returns to normal after cooling down ?? ......

That's what I was thinking too .. possibly either a heating up issue, or an intermittent electronics issue. The lens itself has almost as many electronic components as does the camera nowadays!

Anyhow, hopefully it'll be a simple fix for the OP.

[mongo]

Today, Mongo tried out the 70-200VRII on the D4s in continuous AF/tracking mode for quite some time. Mongo deliberately moved the lens around continuously at different targets (and everything in between) non-stop for about 5 minutes. Could not get the fault you reported to occur. As Mongo said, he does not think it is the camera - your lens may have an issue. Hope you get it sorted and please let us know what it was.

[Belly]

Thanks for trying out your gear Mongo, appreciate the effort and pleased you don't have this issue. Disappointingly I have not been able to experiment as yet but I will post my findings when I do.

cheers
Belly

Today, Mongo tried out the 70-200VRII on the D4s in continuous AF/tracking mode for quite some time. Mongo deliberately moved the lens around continuously at different targets (and everything in between) non-stop for about 5 minutes. Could not get the fault you reported to occur. As Mongo said, he does not think it is the camera - your lens may have an issue. Hope you get it sorted and please let us know what it was.

[Belly]

Hi again posters...

My focus issues are definitely coming from the lens. This, after having cleaned the CPU contacts and testing using other other lenses and both D4s bodies. Thanks again for your interest and feedback.

cheers
Belly