After using the D700 for 3 months and loving it, I discovered a problem with it y'day. The following things need to happen to reproduce this behavior.

1. Lens AF is on.
2. D700 AF is set to back button, not shutter half-press.
3. AF at a particular distance, recompose, and then trip the shutter using the interval timer.
4. The camera changes the focus just as it does if AF is set on shutter half-press. Except, shutter half-press AF is disabled as in step 2.

Anyone else knows about this problem and how to work around it? I am afraid a lot of my good shots have been ruined by this behavior.

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Abhijit

I would first recheck your settings. The only way I can repro this problem is to have the AF set to the shutter button. When set to af-on only, my D700 behaves as desired and expected.

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Joseph K
Seattle, WA, USA

D700, D200, D70S, 24-70mm f/2.8, VR 70-200mm f/2.8 II, 50mm f/1.4 D,
17-55mm f/2.8 DX, 70-300mm f/4.5-5.6 VR, 18-70mm f/3.5-4.5 DX

did you have your focus mode selector switch set to C ( instead of S) by chance?

Sheri Becker

Visit my Nikonians gallery.

Did you try to lock AF with the AE/AF lock?


Anthony

The Moderator Page and My Gallery
The important things in life are simple; the simple things are hard.

>did you have your focus mode selector switch set to C (
>instead of S) by chance?


Yes, I've focus mode selector at 'C'.

>Did you try to lock AF with the AE/AF lock?
>
>
>Anthony

I've AE/AF set for AE, not AF.

I do not know if its supposed to or not ..but I think that is your culprit..I had the same problem..change to single servo and see if it does it..
From "Mastering the Nikon D700" book
When the subject is standing still, Continuous-servo AF acts a lot like single -servo AF with the exception that the focus never locks.If you have camera movement, you may hear chattering a little as the autofocus motor makes small adjustments in the focus position.Since it never locks in this mode you need to be careful that you do not accidentially move the AF sensor off of the subject because it may focus on something in teh background instead" (pg.44)

Sheri Becker

Visit my Nikonians gallery.

This is a good point.

In step #3 of the OP, I assumed he released the AF-ON button before doing the recompose.

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Joseph K
Seattle, WA, USA

D700, D200, D70S, 24-70mm f/2.8, VR 70-200mm f/2.8 II, 50mm f/1.4 D,
17-55mm f/2.8 DX, 70-300mm f/4.5-5.6 VR, 18-70mm f/3.5-4.5 DX

>> 3. AF at a particular distance, recompose, and then trip the shutter using the interval timer.

Are you using the "Self timer" activated from the shooting mode dial on the top left camera, or are you using the menu based intervalometer?

I don't know why it would matter, or if it would matter but if anyone is going to try to reproduce it they would want the identical settings.

What is your AF-C priority mode setting (custom a2)?

I am very sure I don't have the problem you are having but I may be skinning the cat differently. The key, as mentioned previously, is to have "AF Activation" (custom menu a5) set to OFF. And you seem to be sure you have that set correctly.

AF-S mode would not solve the problem because the camera would not fire. Same if in AF-C focus priority mode.

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Neil
Nikonians Team
My Gallery

>Are you using the "Self timer" activated from the
>shooting mode dial on the top left camera, or are you using
>the menu based intervalometer?

Intervalometer or more specifically Interval timer shooting, I've added it to My Menu and access from there.

>What is your AF-C priority mode setting (custom a2)?
>
a2 AF-S priority selection=focus

However, since I am using AF-C and not AF-S, I believe the relevant setting is
a1 AF-C priority selection=Release + focus

I rechecked, c1 Shutter-release button AE-L=OFF

I tried changing f7 Assign AE-L/AF-L button=AE-L/AF-L button press >> AF lock only, but that requires me to hold the button down during shooting and Intervalometer can't be used if I am holding the button down. Unfortunately, it doesn't have an option like AF lock (hold).

>I am very sure I don't have the problem you are having but I
>may be skinning the cat differently. The key, as mentioned
>previously, is to have "AF Activation" (custom menu
>a5) set to OFF. And you seem to be sure you have that set
>correctly.
>
>AF-S mode would not solve the problem because the camera would
>not fire. Same if in AF-C focus priority mode.

In AF-C, the camera can be made to fire without locking a focus by changing a1. See my answer above.
a5 AF activation=OFF

According the an article that I was directed to by a Facebook group I am a member of, this is a known behavior. "Unless your camera is set to ‘Manual Focus,’ the Interval Timer will attempt to focus before each set of shots."
http://mariloujaen.com/images/blog/Love-Your-Nikon-D700/D700-Episode1-Interval-Timer.rs.pdf

I am too lazy to write to Nikon but I am planning to.

I wrote to Thom Hogan and according to him, this is how all Nikon cameras operated for last 20 years. The only way to avoid it is to set the AF off on the lens or on the camera body.

I've just decided to switch to manual focus after I've auto-focussed at a particular distance.