Rob Studdert writes:
> What equipment/set up was used to perform the shutter speed tests?
I was saving that for the web page :)
Basically all I did was shine a low-power laser into the shutter, with a small
silicon photocell on the other side, so the photocell gets lit up while the shutter
is open.
Attached to the photocell was a digital oscilloscope in single-shot mode,
triggering off the rising edge. The 'scope has an automatic pulse-width
measurement so I just used that to measure how long the shutter was open.
The 10mW laser gave me about 400mV (or 0.4V for the non-metric) out of the
photocell so I had plenty of signal to work with.
It worked well until the really high shutter speeds (above 1/1000 on the Z-1p)
where a combination of the speed of the silicon cell and the width of the slit
relative to the beam caused inaccuracies. That's my theory, anyway.
All the rest of the work (converting all the info into "X stops over/under") was
done using a spreadsheet.
Cheers,
- Dave
David A. Mann, B.E. (Elec)
http://www.digistar.com/~dmann/
"Why is it that if an adult behaves like a child they lock him up,
while children are allowed to run free on the streets?" -- Garfield
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