Hi Alex,
If you want the answer, check out with Popular Photography Sept 99
issue. It compared the AF accuracy and manual focus accuracy of Canon
EOS-1N, Nikon F5 and Maxxum 9. All the results shown that manual focus
are more accurate than the AF, in an extreme case the Nikon F5 with
50/1.4 get 29 lpmm at AF and 47 lpmm at manual focus.
There was also an essay from one older Pop Photo issue, which prepared
by Herbert Keppler, mentioned the AF CCD sensor's max accuracy was
only around 47 lpmm (if my memory serve), but in most case with some
software technique, the resolution will be a bit higher. The technique
could be similar to manual focus on matte area of focusing screen,
turn the focus left-right-center to get the sharpest point. On that
issue the Nikon 60/2.8 macro is used for test and in all cases the
manual focus is much better than the AF.
IMHO, if you know how to focus with the matte area of the focusing
screen (plus a good vision of course), you will get the best
resolution from your lenses. With the low resolution magazine (even
175 line screen is nothing and sharpen are always added before
printing), you will not see what is really sharp, same case as the low
resolution web images.
C.H.Ling
-----Original Message-----
From: Alexander Fisher Wilson <a.f.w@xxxxxxxxxxxxxx>
To: olympus@xxxxxxxxxxxxxxx <olympus@xxxxxxxxxxxxxxx>
Date: Saturday, March 25, 2000 8:04 PM
Subject: Re: [OM] Going autofocus (Was 300mm 2.8 and things to come!!)
>This topic was raised a couple of weeks ago regarding a site which
was
>critical of AF cameras and lenses. Below is a repeat of my posting to
that -
>and it still hasn't been answered.
>
> "According to the information , it would seem to be very difficult
to get
>really sharp images from autofocus cameras on either AF or M mode and
>certainly not with IS. My question is : whence come all those
excellent
>images - seemingly pin - sharp - that I constantly see in magazines,
>newspapers and books and on web galleries, many - if not the
majority -
>apparently taken by autofocus cameras, often in the hands of
professional
>photographers? "
>
>I might add that most of then appear at least as sharp as those on
any of
>the Olympus web photo sites that I've seen - including ADTL. On web
>galleries such as World Photo Gallery or Photocritique, the OM images
do not
>seem to me to be sharper to any degree at all than those of autofocus
>cameras.
>
>Alex Wilson
>
>
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