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View Full Version : Nikon Users - How much for a lens AF recalibration?

Cheng
26-06-2009, 21:57
Recently got a used 35-70 and I'm 99% sure it front focusses by 1cm or so. I've taken shots with flash at faster shutter speeds than the focal length, and used printed text totally flat to the camera. I've taken the shot via AF, then locked focus again and moved the camera 1cm forward - the second shot is always considerably sharper. Repeated this several times with two D200 bodies.

So how much would it cost roughly for me to send the lens to Nikon to recalibrate the AF?
puddleduck
27-06-2009, 03:58
These sort of lenses can't be recaliberated. The camera body decides where to focus.

Most Nikon camera body manuals refer to this lens (typo so its called the 35-70 S) and say there will be focus problems shooting objects up close, its mentioned in the lens compatibility table.

You could ask for the lens to be "shimmed" (which places thin metal rings within the lens to manually adjust the focus point), but caliberation just can't be done.
Cheng
27-06-2009, 08:47
In the manual, it only says it will not accurately display the focus dot when using manual focus, but no mention of focus problems when using AF?
puddleduck
27-06-2009, 09:40
In the manual, it only says it will not accurately display the focus dot when using manual focus, but no mention of focus problems when using AF?

The focus dot is tied to the AF module. So what Nikon doesn't say is as important as what they do say...
Cheng
27-06-2009, 10:38
I've just checked a used 50mm 1.4 I bought - it was soft wide open which I thought was to be expected - however, just took a few photos with text flat against the wall - so basically 90 degrees to it - and that ALSO front focusses on both my D200s again by about 1cm. Forget what has been about it being soft wide open - in the centre this thing is SHARP! But before you suspect two defective bodies, I did the same test with my 18 - 200 VR and 1.8 50 - and those are pretty much bang on perfect, with the 1.8 just a few mms front (but certainly acceptable).

So I don't think it's the bodies...?
Cheng
27-06-2009, 11:02
Regardless of which, to get back to the original topic - how much would a lens recalibration by? For the 35-70mm and for the 50mm 1.4 (non D)?
puddleduck
27-06-2009, 11:11
You won't get a charge for the 35-70 because it can't be caliberated. So you'll just get have to pay Nikon's return postage fee.
Cheng
27-06-2009, 11:57
How much would the 50mm roughly then? Could you point me to where it says the 35-70mm can be shimmed and not calibrated?
puddleduck
28-06-2009, 06:43
How much would the 50mm roughly then? Could you point me to where it says the 35-70mm can be shimmed and not calibrated?

Why not ask Nikon?

I'm trying to save you unnecasary postage and being told that your 35-70 f/2.8 is within spec (as the "problem" is well documented, widely reported and lies in some post film AF modules), but as this doesn't seem to be sinking in, suggest you talk to Nikon.
Cheng
28-06-2009, 08:46
Why not ask Nikon?

I'm trying to save you unnecasary postage and being told that your 35-70 f/2.8 is within spec (as the "problem" is well documented, widely reported and lies in some post film AF modules), but as this doesn't seem to be sinking in, suggest you talk to Nikon.

Because its a weekend, and fixation appears to be closed...

And I wasn't disputing the fact it couldn't be calibrated, I was merely asking you to cite your sources for 'shims' as I am interested in them and would like to find out more...