focus problem with Nikkor 35-70 at 4-6 feet...ish

Archived from groups: rec.photo.digital.slr-systems (More info?)

Hi all,

Maybe its me, but I really don't think so. I'm using a Nikkor 35-70 zoom
(f2.8) with a D1x and I have had a recurring problem with focus under
certain conditions.

I decided to try a little test exercise this afternoon, and took several
oblique shots of a pen placed at various distances on a rubber mat with a
grid design on it.

It was easy to focus and I'm not sure what I hoped to prove, but while the
other shots were fine, the shot of the pen at 5 feet was way out of focus.
It is definitely a focus issue, I used flash, on a tripod, with the lens
wide open. You can see the strap of my camera bag about foot further away,
pin sharp! I used the lens fully zoomed in for the test, but zoomed in and
out fully between each shot. Zooming in and out fully with the lens is not
a very graceful procedure as there is a surprising "bump" when you reach
the limits at either end of the zoom.....

Any thoughts?

I'm completely capable of making mistakes, but I've had similar results at
this sort of distance a number of times, and I had all the time in the
world (and ideal conditions) to focus during the test. :-/








All the best,
Angus Manwaring. (for e-mail remove ANTISPEM)

Archived from groups: rec.photo.digital.slr-systems (More info?)

Angus Manwaring <angus@angusm_antispem_.demon.co.uk> wrote:

> It was easy to focus and I'm not sure what I hoped to prove, but
> while the other shots were fine, the shot of the pen at 5 feet was
> way out of focus. It is definitely a focus issue, I used flash, on
> a tripod, with the lens wide open. You can see the strap of my
> camera bag about foot further away, pin sharp!

OK. Can you let us see this picture? I think I know what might be
happening, but need to see it.

Andrew.

Archived from groups: rec.photo.digital.slr-systems (More info?)

Angus Manwaring <angus@angusm_antispem_.demon.co.uk> wrote:
> On 18-May-05 09:43:12, andrew29 said
>>Angus Manwaring <angus@angusm_antispem_.demon.co.uk> wrote:

>>> It was easy to focus and I'm not sure what I hoped to prove, but
>>> while the other shots were fine, the shot of the pen at 5 feet was
>>> way out of focus. It is definitely a focus issue, I used flash, on
>>> a tripod, with the lens wide open. You can see the strap of my
>>> camera bag about foot further away, pin sharp!

>>OK. Can you let us see this picture? I think I know what might be
>>happening, but need to see it.


> Its a bit tricky for me to organise that Andrew - I don't have internet
> access at work.... and the image is currently on a computer that doesn't
> belong to me.

> Can you give me any clues?

My gess is that your camera focussed on a strong contrast subject just
outside the area marked as the focus sensor. Either that, or perhaps
a little movement after focussing?

Andrew.