Hi Pål
>But the question is; does it use it for focusing? Or is it only used for
flash
>metering and power zooming?
I'm pretty sure the PZ/Z series uses the information for Image Size Tracking
only. It makes no sense that it (or an MZ-S for that matter) would use such
info for focus. How could the AF system know, before it achieves focus, how
far away the object is? As strange as this may sound, I can see no place in
an AF system for distance information, especially distance information that
only has meaning once focus is achieved.
FWIW, I don't think the info is used for flash either, but that is easy
enough to check.
>The MZ-S has several AF points and the AF point selection works by taking
into
>consideration the distance to the subject from the various focus points.
Also, the
>MZ-S seems to hunt more intelligently; ie. not through the whole helicoid
like the
>Z-1p, but often near the actual focus plane as if it knows where the actual
focus
>plane should be located before it goes looking for it.
How? See my comment above. It has no way of knowing how far away the
object is until is acheives focus
> Only if this fails does it
>start spinning thruogh the whole focus range. This is just my impression I
have after
>using the camera for a week.
>I don't know what the problem is; just that the MZ-S goes bananas with the
FA 600/4
>when the Z-1p don't. I can only assume that there some data exchange
problems between
>the lens and the camera.
Pål I can think of only one reason for what you are describing. If the
plane of focus of the lens is not fully parallel with the plane that the
focus CCD's are in, then you will not get an image in focus at all points
across the CCD. As you know, the depth of focus of a 600/4 at the focus
CCD's would be vanishingly small such that only a slight misalignment would
cause the problem. If what you said in an earlier post is true about your
front element groups being loose, this could indeed be your problem.
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