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Re: [OM] OT Auto Cam Questions

Subject: Re: [OM] OT Auto Cam Questions
From: Andrew Dacey <frugal@xxxxxxxxxxxxxxx>
Date: Thu, 07 Feb 2002 22:08:35 -0400
On 2/7/02 7:26 PM, "W.Xato" <xato0@xxxxxxxxx> wrote:

> My guess is that the 5 point AF system is really a 5
> zone system, which means that there are 5 focusing
> zones from near to far. Its better than fixed focus
> and should work ok with a 35mm lens in daylight.
> Second guess is that the metering system is a smaller
> spot set into a larger area. These are usually biased
> so that if the central area is darker than the
> surround the lens will open up or the flash will go
> off. 

Actually, I believe focusing points refer to how the sensors are arranged in
the viewfinder. Older AF cameras had 1 focusing point (in the centre). Newer
AF systems have other AF sensors away from the centre. In my C*n*n Elan Iie,
there a 3 focusing points, 1 in the centre, and a left and right sensor. The
5 point system would add 2 more (top and bottom?). What this does, is allow
for the AF system to focus on subjects not in the centre of the frame and
with more advanced cameras, follow motion. Usually, there will be some
method for selecting which focusing point to use. Or, you put it in an AF
mode designed to track the subject as it moves. Be aware though that usually
only the central sensor is sensitive to both vertical and horizontal
subjects (a cross sensor), the others are usually only sensitive to one or
the other (I think they will work with the other type but just not as
accurately).

The passive AF means that it's not using any kind of focusing aid (like an
infrared assist light). And the distance is just the limit to how close it
will work.

Not sure what the metering system means though. Unless it's something like a
centre sensor and then a wider sensor, allowing you to switch between a
smaller or larger metering area.

-- 
Andrew "Frugal" Dacey
frugal@xxxxxxxxxxxxxxx
http://www.tildefrugal.net/


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