Here is my try:
> 1] If one is not using any of the special zoom effects (such as IST), of
> what use is the power zoom? Doesn't it just do the exact same thing you
can
> also do manually, without draining batteries?
It acts like the zoom of the video cameras and today's point and shoots. You
zoom between W and T with a push of a button (the variable speed is an extra
here ofcourse). You are right to wonder what such a consumer oriented option
is doing in a pro-grade camera but as somebody already noted having all the
other power zoom options this one is just for completeness... :)
> 2] When one selects the MTF program line, the manual says it makes the
> camera select the aperture on an AF lens "at which that lens is sharpest".
The manual also sais, "The nesessary data is stored in the FA lense in use".
There was a discussion here recently what is the difference between the F
and FA lenses and somebody answered that it's the chips. Obviously the new
FA chips store this "extra" information how sharp the particular lense is at
different appretures. It is like having the whole lense sharpness test
stored in a chip (smart!). When the computer picks an exposure value it will
always try to keep closer to the sharpest appretures. All this is more
complicated with the zooms ofcourse. Having Appreture and Shutter Priorities
for a long time with the automatic cameras it is may be time to pattent this
Sharpness Priority Mode :) What the diffrences between the program lines are
is easyer to see on the graphs at the end of the manual (p.126, 127).
> And pray tell, what in the world does the "Normal" program line do? I
mean,
> what's left for it?
Again, see the graphs. It seems that the Normal compromises between Shutter
Pr. and Appreture Pr.
For example (I'm just reading those graphs) at 14EV with the 28-105,
f/4.5-5.6 at 28mm the camera will pick:
Normal: 1/125, f/11 (approx.)
Shutter speed Pr.: 1/500, f/5.6 (approx.)
DOF Pr.: 1/60, f/16 (approx.)
MTF: 1/500, f/5.6 (approx.)
(the one stop difference in these results is because of my approximation
reading the graphs)
Note that in this case MTF is closer ot Shutter speed than to DOF Priority
(answering the question is MTF DOF priopity).
> Here's a little poll for someone to run: which aperture does the Z-1(p)
select
> in MTF mode as "optimum", for each FA lens? I think that with all the
> lenses I've tried (100/2.8 macro, 24/2.0, 43/1.9 Limited) it went straight
for
> f/5.6.
Although the graph in the manual is for 28-105, f/4.5-5.6 it answers it very
well. Actually, reading all those lense tests I got the impression that the
lenses are sharper at the middle - f/8, f/11. What is this 5.6 doing here?
Another thing which I wonder is if the high quality Pentax FA primes come
with similar graphs how would PZ-1p's MTF behave with them. This would be
helpful even without PZ-1p. The 28-105, f/4.5-5.6 example in the manual is
instructional but nothing more...
Cheers,
I.
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