D700 focusing tricks?

Foques

Greetings,

I am experiencing a bit of a problem with one of my bodies.
The issue started out of the blue, and most notable on my 85mm 1.4; When shooting at 1.6/1.8, it seems that the focus shifts a bit; mainly, it seems to be a backfocusing issue.

Are there any ways to reset the focusing calibration?

I did check, and sensor appears to be clean, no fine tune for focus is enabled.
Not sure where to go from here; I'd very much like to not send the camera out given that I cannot easily reproduce this.
thoughts?

insanefred

Is it a G or D type lens? I noticed with a few camera bodies that when I used a lens with the screw type autofocus, they're never 100% accurate or consistent; especially under f/2.8.
Also, are you using single point, single servo with the center point selected and mount your camera on a tripod and photograph a static object?

Matthew Saville

There's really no way of knowing what your problem is unless you can get that puppy on a tripod with a cable release and do some serious testing. I know it sounds dumb, but focus calibration is the one thing where I don't hesitate to be as nerdy and pixel-peeping as I need to be.

There is a good chance that your camera, or rather the camera and lens combination, have a tiny issue that may need to be resolved with a little bit of tweaking to the D700's AF microadjustment options. HOWEVER, your reference to the apertures of f/1.6 to f/1.8 alone have me puzzled, so I would rather have you test all apertures very thoroughly in order to make sure the issue is consistent...

=Matt=

Qarik

matthew saville wrote: »

there's really no way of knowing what your problem is unless you can get that puppy on a tripod with a cable release and do some serious testing. I know it sounds dumb, but focus calibration is the one thing where i don't hesitate to be as nerdy and pixel-peeping as i need to be.

There is a good chance that your camera, or rather the camera and lens combination, have a tiny issue that may need to be resolved with a little bit of tweaking to the d700's af microadjustment options. However, your reference to the apertures of f/1.6 to f/1.8 alone have me puzzled, so i would rather have you test all apertures very thoroughly in order to make sure the issue is consistent...

=matt=

+1

Foques

sorry about the delayed reply. an ethug had to show that he was a bigger man.

Matt, you were spot on.
there were two issues.
the lens that really showed the signs of poor focus had dirty front element. I cleaned it proper, and it focused mostly ok.

I ended up purchasing the lensalign, and it took care of all the other concerns.

Many thanks to you gents.

piero

Thanks for sharing. I had the same problem with my D700 / 50mm 1.8 and is fixed now.
Many thanks
Piero