Bigbar update

[Greg Erker <erker@xxxxxxxxxxxxxx>]

  I finished the preliminary work on my 12'
bar (for taking fireworks photos) on the
weekend. Then I mounted it on my two tripods
and mounted the Ricohflex's at each end.

  I didn't like what I saw. The bar sagged
quite a bit, partially due to the tripods
still being 4' apart. But more serious was
the oscillation problems. The cameras (if
bumped or whatever) would vibrate for 7
seconds or more before dying down.

  I had intentions of moving the tripods
further apart but wanted to keep them
so that I can reach both tilt knobs at
the same time to be able to tilt the
cameras up or down (by myself).

  In the end I decided to remove the new
extension from one end and go with a 10'
bar. I moved the one tripod mount over
about 1.5' which was pretty much the most
I could go and still reach both tilt handles.

  After this fix the damping seems a bit
better, or at least the flex is lower so
they don't bounce quite as much.

  I have a little more work to do on it
and need to get some longer cable releases
(and film too) then I should be ready to
go.

---

  I think the 12' damping problem could
be solved with something like a light chain
going to a bean bag (resting on the ground)
at each end. The beans would damp out the
vibrations quite a bit quicker I assume.
But I wasn't willing to try it this year
and lug the extra weight along.

  The sag in the long bar could be lived
with by just shimming the two camera mounting
plates to make them level in spite of the
sag. I'll be doing that on the 10 footer
anyway.

  So the 12 foot superbar might have to
wait until 2001, assuming ever two years
is as often as I want to go to all this
trouble :)

Greg