Re: "The exposures are at 1/100,000,000ths of a second"

In article <k3e6v1h6aq6tte28tm79ekjvaj05h90gti@xxxxxxx>, Ed Ruf <egruf_usenet@xxxxxxx> writes
On Wed, 15 Feb 2006 01:19:31 -0500, in rec.photo.digital Andy Williams
<invalid@xxxxxxxxxxxxxxx> wrote:

Rich wrote:

I'm not sure how they did those shots, but there have been
cameras that have used things like spinning octagonal or
multi-sided mirrors that could "flash" exposures across several
feet of filmstock in a fraction of a second. For slower (but still
fast) shooting, cameras have been equipped with high speed
motor winders that took movie film at a high rate of speed,
thousands of frames per second.

Mechanical devices are orders of magnitude too slow to achieve these
results. Repeat of a post to r.p.e.35mm:

Alan Browne wrote:

Probably a high speed cine camera, eg, 1000's of frames per second with
exposure times on the order of 1/4000 to 1/10,000

Exposure time was much less, on the order of ten nanoseconds. Google
rapatronic. Each camera took one frame. A starting point:

http://simplethinking.com/home/rapatronic_photographs.htm

Another type of device used for quick exposures is an image converter
camera. I used a Navy surplus 1950 EG&G one in grad school. IIRC, the
framing module would do three 10nS frames at microsecond spacing.
For the theory see, http://www.iop.org/EJ/abstract/0950-7671/38/3/306

Indeed, and here is a more recent example:
http://www.linuxdevices.com/articles/AT2171151224.html

There are solid state versions available now as well, which are capable of being synchronised with a high speed laser pulse to illuminate a depth of less than a metre at ranges of many km, enabling a full 3D structure to be visualised.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
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