Lee Love on thu 28 mar 02
----- Original Message -----
From: iandol
>They just increase the opacity. Blue still comes from adsorption of longer wave
lengths
>and reflection of the shorter.
the sky is blue.>
The blue is an optical effect, like the blue in the sky. Please excuse
me for using the word prism.
Opacity does help the color, especially if you have anything other
than a white body underneath, (like copper slip) because it blocks the color, to
varying degrees, according to the thickness of the glaze and/or bubbles.
Both the bubbles and the blue color are needed for a true chun.
Otherwise, you just have a light blue celadon. The opacity is a very
important
in how the copper slip interacts with the glaze. This is what helps give you
the
range of colors from pink, red to blue and purple from the copper. I cannot
think of Chun without copper either.
I doubt that it is the residual carbon in the bone ash that causes the
bubbles. There is twice as much wood ash in the glaze. My red elm ash came
from a fireplace and I don't wash the wood ash. I just sieve it through 30mesh
(you can see the black floaties in the glaze.) The fireplace ash is burnt at a
very low temperature compared to the temperature needed to create bone ash.
Also, there doesn't seem to be any difference between natural bone ash and
synthetic. No residual carbon in synthetic. Better chance of residual
carbon from the ash. But you don't have bubbles if you exclude the bone ash
and use the wood ash.
Below explains why the Sky is blue. It is not because of the
absorption of _other_ colors.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
http://www.sciencemadesimple.com/sky_blue.html
WHY IS THE SKY BLUE?
The blue color of the sky is due to Rayleigh scattering. As light moves through
the atmosphere, most of the longer wavelengths pass straight through. Little of
the red, orange and yellow light is affected by the air.
However, much of the shorter wavelength light is absorbed by the gas molecules.
The absorbed blue light is then radiated in different directions. It gets
scattered all around the sky. Whichever direction you look, some of this
scattered blue light reaches you. Since you see the blue light from everywhere
overhead, the sky looks blue.
http://www.sciencemadesimple.com/sky_blue.html
--
Lee in Mashiko
._____________________________________________
| Lee Love ^/(o\| Practice before theory. |
| Ikiru@kami.com |\o)/v - Sotetsu Yanagi - |
`~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~'
"All weaves one fabric; all things give
Power unto all things to work and live." - Goethe -
Longtin, Jeff on thu 28 mar 02
Now for something completely different:
A few years ago I got a call from a woman wanting to buy a Braille cup.
She asked what colors they come in.
"I have white cups with blue letters(and Braille) and blue cups with white
letters (and Braille)".
"Oh I'll take the blue cup! I just love the color blue!".
"Super...So you're sighted ma'am?"
"Oh no I've been blind since birth! I just love the feel of blue!".
You learn something new every day!
Jeff Longtin
-----Original Message-----
From: Lee Love [mailto:Ikiru@KAMI.COM]
Sent: Thursday, March 28, 2002 5:44 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Chun and The Blue Sky.
----- Original Message -----
From: iandol
>They just increase the opacity. Blue still comes from adsorption of longer
wave
lengths
>and reflection of the shorter.
why
the sky is blue.>
The blue is an optical effect, like the blue in the sky. Please excuse
me for using the word prism.
Opacity does help the color, especially if you have anything
other
than a white body underneath, (like copper slip) because it blocks the
color, to
varying degrees, according to the thickness of the glaze and/or bubbles.
Both the bubbles and the blue color are needed for a true chun.
Otherwise, you just have a light blue celadon. The opacity is a very
important
in how the copper slip interacts with the glaze. This is what helps give
you
the
range of colors from pink, red to blue and purple from the copper. I
cannot
think of Chun without copper either.
I doubt that it is the residual carbon in the bone ash that causes
the
bubbles. There is twice as much wood ash in the glaze. My red elm ash
came
from a fireplace and I don't wash the wood ash. I just sieve it through
30mesh
(you can see the black floaties in the glaze.) The fireplace ash is burnt
at a
very low temperature compared to the temperature needed to create bone ash.
Also, there doesn't seem to be any difference between natural bone ash and
synthetic. No residual carbon in synthetic. Better chance of residual
carbon from the ash. But you don't have bubbles if you exclude the bone
ash
and use the wood ash.
Below explains why the Sky is blue. It is not because of the
absorption of _other_ colors.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
http://www.sciencemadesimple.com/sky_blue.html
WHY IS THE SKY BLUE?
The blue color of the sky is due to Rayleigh scattering. As light moves
through
the atmosphere, most of the longer wavelengths pass straight through. Little
of
the red, orange and yellow light is affected by the air.
However, much of the shorter wavelength light is absorbed by the gas
molecules.
The absorbed blue light is then radiated in different directions. It gets
scattered all around the sky. Whichever direction you look, some of this
scattered blue light reaches you. Since you see the blue light from
everywhere
overhead, the sky looks blue.
http://www.sciencemadesimple.com/sky_blue.html
--
Lee in Mashiko
._____________________________________________
| Lee Love ^/(o\| Practice before theory.
|
| Ikiru@kami.com |\o)/v - Sotetsu Yanagi - |
`~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~'
"All weaves one fabric; all things give
Power unto all things to work and live." - Goethe -
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