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Aaronvan
Jun18-11, 06:21 PM
I’m not sure if they are even used anymore, but back in the day engineers used spark cameras to capture very brief timescale events.

Bob S
Jun18-11, 10:12 PM
They were used only until Harold Edgerton showed he could take an aerial photo of MIT at midnight using a flashtube mounted on the belly of a B-18 in 1941. See

http://invention.smithsonian.org/resources/online_articles_detail.aspx?id=618

Also see http://www.springerlink.com/content/k96yxljy0tt29rgx/

Henry Talbot is purported to be the first user of spark photography in the 1850's.

Bob S

Aaronvan
Jun19-11, 11:26 PM
Thanks, I wish I could read that Shock Waves journal article. It looks really interesting. Another question: did X-ray radiography replace spark photography?

wildcatherder
Jun20-11, 04:54 PM
By the way, how do spark cameras work?

Mech_Engineer
Jun20-11, 05:25 PM
When you call it a "spark camera," what exactly do you mean? Do you mean a conventionally shuttered camera with a fast flash which exposes the object while the shutter is open?

Bob S
Jun21-11, 03:11 PM
When you call it a "spark camera," what exactly do you mean? Do you mean a conventionally shuttered camera with a fast flash which exposes the object while the shutter is open?
For a camera with a shutter, the shutter is in T (time) mode, in a dark room. For view cameras, the lite-tite dark slide on film holders is pulled out. Sparks in air generally do not give a uniform spectral (white light) distribution. Electronically triggered flash lamps were a major upgrade. Triggering a spark discharge in air was usually done by manually discharging a capacitor bank, so synchronizing with a shutter was difficult.