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Has anyone else found that their Minolta A1 occasionally gives a "correct
focus" indication (green dot in viewfinder) but the resulting photo is out
of focus?

I've eliminated camera-shake as the cause of my blurred photos (some blurred
ones are at 1/1000 sec). It seems to be mainly when the lens is towards the
wide-angle end of the zoom and it's when I'm taking pictures where the whole
of the subject is at infinity - there's no window or nearby piece of grass
that the camera could be focussing on, yet the result is as if it had
focussed at about 1 metre. Sadly the viewfinder and back-of-camera screen
are not good enough to use as focussing aids, and the picture appears sharp
when viewed at normal size: you can only tell that it's blurred when you
zoom right in.

Before I return the camera as faulty, I wanted to gauge how widespread the
problem is.

On Wed, 14 Jul 2004 15:30:03 +0100, in rec.photo.digital "Martin
Underwood" <> wrote:

>Has anyone else found that their Minolta A1 occasionally gives a "correct
>focus" indication (green dot in viewfinder) but the resulting photo is out
>of focus?
>
>I've eliminated camera-shake as the cause of my blurred photos (some blurred
>ones are at 1/1000 sec). It seems to be mainly when the lens is towards the
>wide-angle end of the zoom and it's when I'm taking pictures where the whole
>of the subject is at infinity - there's no window or nearby piece of grass
>that the camera could be focussing on, yet the result is as if it had
>focussed at about 1 metre. Sadly the viewfinder and back-of-camera screen
>are not good enough to use as focussing aids, and the picture appears sharp
>when viewed at normal size: you can only tell that it's blurred when you
>zoom right in.
>
>Before I return the camera as faulty, I wanted to gauge how widespread the
>problem is.

First, does the exif info contain any focus distance info to verify
your contention?
__________________________________________________ ______
Ed Ruf Lifetime AMA# 344007 ()
See images taken with my CP-990 and 5700 at
http://EdwardGRuf.com

Martin Underwood wrote:

> Has anyone else found that their Minolta A1 occasionally gives a "correct
> focus" indication (green dot in viewfinder) but the resulting photo is out
> of focus?
>
> I've eliminated camera-shake as the cause of my blurred photos (some blurred
> ones are at 1/1000 sec). It seems to be mainly when the lens is towards the
> wide-angle end of the zoom and it's when I'm taking pictures where the whole
> of the subject is at infinity - there's no window or nearby piece of grass
> that the camera could be focussing on, yet the result is as if it had
> focussed at about 1 metre. Sadly the viewfinder and back-of-camera screen
> are not good enough to use as focussing aids, and the picture appears sharp
> when viewed at normal size: you can only tell that it's blurred when you
> zoom right in.
>
> Before I return the camera as faulty, I wanted to gauge how widespread the
> problem is.
>
>

My 7Hi does that. I use only the point focusing and never the wide, but
every now and then I just get an out of focus image. I always check to
make sure the dot is white too.

I don't know why this happens, but it does make me shoot 2 or 3 of
everything.

Clyde

"Clyde" <> wrote in message
news:GecJc.78915$IQ4.30779@attbi_s02...
> Martin Underwood wrote:
>
> > Has anyone else found that their Minolta A1 occasionally gives a
"correct
> > focus" indication (green dot in viewfinder) but the resulting photo is
out
> > of focus?
> >
> > I've eliminated camera-shake as the cause of my blurred photos (some
blurred
> > ones are at 1/1000 sec). It seems to be mainly when the lens is towards
the
> > wide-angle end of the zoom and it's when I'm taking pictures where the
whole
> > of the subject is at infinity - there's no window or nearby piece of
grass
> > that the camera could be focussing on, yet the result is as if it had
> > focussed at about 1 metre. Sadly the viewfinder and back-of-camera
screen
> > are not good enough to use as focussing aids, and the picture appears
sharp
> > when viewed at normal size: you can only tell that it's blurred when you
> > zoom right in.
> >
> > Before I return the camera as faulty, I wanted to gauge how widespread
the
> > problem is.
>
> My 7Hi does that. I use only the point focusing and never the wide, but
> every now and then I just get an out of focus image. I always check to
> make sure the dot is white too.
>
> I don't know why this happens, but it does make me shoot 2 or 3 of
> everything.

Ah, it happens with the 7Hi as well, does it? My dad's got a 7i and has
never had a problem.

I always use cross-hair (point) focussing and not rectangle (region)
focussing - except when it changes back spontaneously and I don't notice!
But I'm confident that I've had focussing problems with both focussing modes
and I know that it's happened when I've had a focus confirmation rather than
a red "cannot focus" signal.

Unfortunately the focus distance is one of the few parameters which isn't
recorded in the EXIF information - that was the first place I looked to see
what the camera had focussed on. I'm guessing that it's focussing too close
based on the fact that everything is blurred, but that closer objects look
slightly sharper than distant objects. Unfortunately it's so rare that I
can't do any tests to see if the focus is better at a smaller aperture than
a large one due to depth of field.

Could a polarising filter affect focussing? I'm not sure whether mine is a
linear or a circular filter, but I'd have thought that if it was affecting
focussing, it would be an all-or-nothing thing: that I'd get "failed to
focus" rather focussing very close instead of at infinity.

I know what you mean about needing to take several pictures. The only time
it occurs is when I don't bother to check before leaving the scene I was
photographing I tend to take three bracketed photos anyway to choose
the best exposure.

Martin Underwood wrote:

> "Clyde" <> wrote in message
> news:GecJc.78915$IQ4.30779@attbi_s02...
>
>>Martin Underwood wrote:
>>
>>
>>>Has anyone else found that their Minolta A1 occasionally gives a
>
> "correct
>
>>>focus" indication (green dot in viewfinder) but the resulting photo is
>
> out
>
>>>of focus?
>>>
>>>I've eliminated camera-shake as the cause of my blurred photos (some
>
> blurred
>
>>>ones are at 1/1000 sec). It seems to be mainly when the lens is towards
>
> the
>
>>>wide-angle end of the zoom and it's when I'm taking pictures where the
>
> whole
>
>>>of the subject is at infinity - there's no window or nearby piece of
>
> grass
>
>>>that the camera could be focussing on, yet the result is as if it had
>>>focussed at about 1 metre. Sadly the viewfinder and back-of-camera
>
> screen
>
>>>are not good enough to use as focussing aids, and the picture appears
>
> sharp
>
>>>when viewed at normal size: you can only tell that it's blurred when you
>>>zoom right in.
>>>
>>>Before I return the camera as faulty, I wanted to gauge how widespread
>
> the
>
>>>problem is.
>>
>>My 7Hi does that. I use only the point focusing and never the wide, but
>>every now and then I just get an out of focus image. I always check to
>>make sure the dot is white too.
>>
>>I don't know why this happens, but it does make me shoot 2 or 3 of
>>everything.
>
>
> Ah, it happens with the 7Hi as well, does it? My dad's got a 7i and has
> never had a problem.
>
> I always use cross-hair (point) focussing and not rectangle (region)
> focussing - except when it changes back spontaneously and I don't notice!
> But I'm confident that I've had focussing problems with both focussing modes
> and I know that it's happened when I've had a focus confirmation rather than
> a red "cannot focus" signal.
>
> Unfortunately the focus distance is one of the few parameters which isn't
> recorded in the EXIF information - that was the first place I looked to see
> what the camera had focussed on. I'm guessing that it's focussing too close
> based on the fact that everything is blurred, but that closer objects look
> slightly sharper than distant objects. Unfortunately it's so rare that I
> can't do any tests to see if the focus is better at a smaller aperture than
> a large one due to depth of field.
>
> Could a polarising filter affect focussing? I'm not sure whether mine is a
> linear or a circular filter, but I'd have thought that if it was affecting
> focussing, it would be an all-or-nothing thing: that I'd get "failed to
> focus" rather focussing very close instead of at infinity.
>
> I know what you mean about needing to take several pictures. The only time
> it occurs is when I don't bother to check before leaving the scene I was
> photographing I tend to take three bracketed photos anyway to choose
> the best exposure.
>
>
I don't use a polarizing filter at all. So, I doubt that's it. I don't
know what it doing it though.

Clyde