Suggestions needed with D850 that randomly freezes

[Erik Lund]

... This suggests to me a common factor among those users, but what?

What I read is that they mount their own lenses on all of the cameras,,, and it sounds like it is related to focus, could be the lens is not responding to commands as expected by the camera.
I don't remember if this is MF as well,,, but:

The higher resolution could be a reason for Nikon to opt for more precise focus is achieved by the lens before exposure is allowed,,, and if the AF sensors don't see that sharpness level,,,

[Kenneth Rich]

Is it possible that Nikon has knowingly or unknowingly created artificial intelligence and it is running amok within your 850?

[Ann]

Just a thought (which was triggered by Erik's comment concerning AF):
How are your Continuous AF settings configured?

Try changing AF-C to:  "Release".

[Luke Miller]

Try changing AF-C to:  "Release".

"Release" is my normal setting.  This adds to the mystery since the camera should always fire the shutter when I press the shutter release regardless of focus, but it does not during the freeze.

[Wannabebetter]

*I'm experiencing difficulty posting my full reply.

[Me.Too]

Hi,
Just logged in to say that I am also having this issue of random AF freeze, but I think I know what it might be and will be returning the camera for repair and hopefully the following will be of help other who are having similar issue.

It has happened randomly since purchased December of last year, however last week was out at Kite festival on local beach, 70-200mm attached, all was fine then AF stopped working, I noticed in the viewfinder the aperture was showing f/2.8, I was actually shooting at f/16 1/10sec, so took a few more shots which came out dark, then it just came back to life, AF as normal and back to f/16.

When back home I checked the EXIF,  at the point the AF freeze occurred it showed as though I had my 20mm AIS f/2.8 attached(it was at home), the photos that were showing as being taken at f/2.8 are darker/underexposed, if it was actually f/2.8 they would have been several stops overexposed.
It would seem to me that it is losing contact with the attached lens and defaulting to the setting for my 20mm.

Fortunately I have photographic evidence with EXIF info which might help with diagnosis/repair.
It has also done this with my 300mm f/2.8 VRII

If you search "D850 autofocus freeze"  you will also find this problem on another forum.

The camera will be going back this week, I will report back with results.

MT.

[Me.Too]

Just a quick update.

Nikon has accepted it for repair, and now in a queue.
So, while I wait, I'll upload the photo's that show there is some sort of "disconnect" issue. visible in the exif, as said earlier, my 20mm was at home, and the angle of view is definitely not that of 20mm.

[Me.Too]

I have managed to get a statement of works from them, hopefully have the camera back soon.
Will report back when I am able to give it a thorough testing.

Nikon's Statement Of Works:

Check/adjust body focus to Nikon standard
Repair/Adjust auto focus mechanism/circuit. Check and adjust AF accuracy.
Metering, shutter and exposure accuracy checked - recalibrated if necessary.
Image capture, playback and delete functions checked.
X-sync, hot shoe and speedlight function checked.
Body depth, body focus, AF accuracy checked and recalibrated if necessary.
Image Sensor, optics, mirrors, and viewfinder cleaned.
Firmware version checked and updated if required.

[Luke Miller]

Thanks for the update.  My D850 still experiences random short freezes every 100 shots or so.  But I believe my problem is different from what you are experiencing.  Since I am no longer doing paid work I can live with it for the time being.

[alecdann]

I've had this problem.  In my case, my D850 locked up for several minutes after a shot.  This seems to happen when shooting in Live View.  The only solution I've found is removing the battery and replacing it.  In my case, the issue might be that I had one of my third party batteries in the camera.  I'll post again here if that is the issue.

Another possiblity for symptoms Ive read in this thread could be Long Exposure Noise Reduction which could add time to writing the image to the card.

[Me.Too]

Another update from Nikon.

"Unfortunately due to an unprecedented change in the status of your repair, the technician has identified that the camera requires a new Af-M Lever Unit which is going to delay your repair. "

It would be nice if they could tell me what it is that is causing this problem.

Is there no common denominator with this issue that we all have?. 

[Luke Miller]

The description of the new D850 firmware update (1.03) suggests it is intended to correct the issue I've experienced on two D850s.  I've installed the update and will see if it is, indeed, a fix.

[Sören Hese]

Will install tonight and give a powerfull check the next 7 days - if it turns out to be the problem solver - that is so great news - I will put my cash aside for another one. The freeze issue was making me add a D810 to my arsenal. ...
Will also comment on how it turns out. Regards from Germany! Sören

 

[Me.Too]

Thanks for the reply, didn't see the new update, seems a few more people on Nikon Rumors also been having this issue.

If that is the "fix", not sure why they are replacing my AF-M lever?.

We have a shoot today, would have been nice to have the D850 back, fortunately the D800's still going strong 4+ years.

[Erik Lund]

They will replace the AF-M leaver since it is defective,,,