RE: Shutter timing

[<aah@nofs.navy.mil>]

Argh.  You can't do all-sky photometry if you don't
have an accurate shutter.  This is something you
can control; why be happy with one percent?  You
should be able to time the signal to open and/or
close the shutter to higher accuracy than 1/10 second
with a PC.  You should be able to test the time
necessary to actually finish the motion to high
precision, and see whether it is repeatable.
  I agree that knowing the precise midpoint of an
exposure to the nearest millisecond is overkill
for most applications, but knowing the exposure
duration is important.  Exposure times will change
depending on the application (such as looking at
Landolt standards or bright variables), so don't
be tied to the 100-second regime when thinking
about exposure lengths.
  Can you think of a reason why you would ask the
Stamp to do something while an exposure is taking
place?  I can't.  Why not let it time the exposure
in the most convenient way?
Arne