Re: Differences between "bad" streamers and "good" streamers

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Bert Hickman by way of Terry Fritz <teslalist-at-qwest-dot-net>" <bert.hickman-at-aquila-dot-net>

Hi Sue,

As a gas is transformed into a plasma, it begins to lose its transparency. 
The more conductive (hotter/more electrons) the plasma, the more opaque it 
becomes. In the case of your coil, the streamers were apparently hot enough 
to partially obscure the much brighter light of the electronic flash, 
leaving their shadows on the wall.

BTW, this effect begins to limit how much energy can be transmitted through 
the air when trying to beam a very powerful (ala Star Wars) laser pulse. If 
the laser pulse is too powerful, the air begins to exhibit dielectric 
breakdown, and the resulting plasma begins to absorb significant energy 
from the beam.

Best regards,

-- Bert --
-- 
--------------------------------------------------
Out-of-Print Physics and Engineering Books and
coins shrunk by ultrastrong electromagnetic fields!
Stoneridge Engineering: http://www.teslamania-dot-com
--------------------------------------------------

Tesla list wrote:
>Original poster: "S Gaeta by way of Terry Fritz <teslalist-at-qwest-dot-net>" 
><sgtporky-at-prodigy-dot-net>
>Someone took a picture of my coil with flash. You can barely make out the
>streamers. The wierd part is that there was a solid white background in the
>photo, and in two of the photos it looks like there is a shadow of the
>streamers on the wall. That's impossible! Isn't it????? How can something
>that is light + invisable energy block light?
>Sue
>----- Original Message -----
>From: "Tesla list" <tesla-at-pupman-dot-com>
>To: <tesla-at-pupman-dot-com>
>Sent: Wednesday, April 09, 2003 5:28 PM
>Subject: Re: Differences between "bad" streamers and "good" streamers
>
>  > Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>"
><FutureT-at-aol-dot-com>
>  >
>  > In a message dated 4/9/03 4:26:59 PM Eastern Daylight Time,
>  > tesla-at-pupman-dot-com writes:
>  >
>  > > >You must realize that spark gap tesla coil streamers are NOT bright,
>  > > >I don't care how big and/or powerful your coil is. They are invisible
>  > > >with normal sunlight, hard to see in normal tungsten lighting, and
>  > > >only highly visible in the dark.
>  >
>  >
>  > It is interesting also to consider that many of the sensitive video
>cameras
>  > and digital cameras, as well as time exposures using normal film,
>  > often make the sparks in photos appear thicker and/or brighter than
>  > they appear directly to the human eye.
>  >
>  > John
>  >
>  >
>
>.