Hi,
Mike Wilson said:
>I still think the whole question revolves around financial
>matters, which should come as no suprise to us.
Besides the financial matters, I like the idea of a thick lightweight metal
more then a thinner heavyweight metal.
As you probably know, if you make something twice as thick, it becomes 8
times as stiff, and in case of magnesium alloy compared to chrome alloy, it
will still be lighter.
Futher the diecasting method gives much more freedom in shape. This means
that you can make the shapes lightly rounded, which again gives more
rigidity then flat planes.
When you combine these two qualities, you can create a cover which not only
acts as a cover, but as an integral part of the construction, say part of
the frame and cover at the same time.
There is no way something similar can be realised with formed metal sheet. A
formed metal sheet can only result in a cover piece, with limited shape
possibilities. Look at the titanium and other sheet metal used for the
Contax G, the Konica Hexar RF, etc.., all pretty simple box shaped covers.
Now I have no idea on how the MZ-S is constructed, but I can imagine a super
rigid frame consisting of nothing but the top cover, bottom cover and some
thick and complicated central part, that at the same time doubles up as the
front cover.
Because most of the frame parts are external, you create a lot of internal
free space to build in various components, thus giving the opportunity to
reduce the size of the camera.
The components you build inside this external frame, could then be metal or
plastic, or plastic moulded around a metal sceleton, depending on the which
choice of materials is more suitable for the job.
Now you could say that other diecast alloy's could be used, like the one
used for matchbox model cars etc.., But I think those alloys, with the
exception of the Silumin types used for aluminium car engines, contain a lot
of Zinc, making them quite heavy.
And I'm speculating now but it could be that these magnesium alloys are also
more shock resistant, so don't break easily when you drop a relatively heavy
item on it's relatively thin shell.
This could be the reason why the use of the classic diecast alloys was
limited to internal frames for camera's.
Further if the claim for good dampening properties is true, then it's a
dream for a camera to have a frame that is super rigid, whithouth prolonging
vibrations like a church bell.
In short, I think the use of magnesium diecast alloys is what made the MZ-S
possible, I don't think you can build something remotely close with other
metals, and not even with plastics or carbon composites. And if this can be
realised at more or less reasonable prices, the path to go for a modern
quality camera seems quite clear.
For the corrosion problem, I feel quite confident, because if similar
alloy's are used for sand-casted helicopter parts (Aerospace also has an
aero component), I doubt they would limit the use of helicopters to sunny
and dry weather conditions, because some gear box cover would corrode if
used in rain.
Now you could wait ten year's or so until these quite new magnesium alloy's
have proven themselves beyond any doubt, but I'm willing to take that
chanche, just like Eos1V and F100 owners are doing.
Just my opinion,
Erwin
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