You keep posting this link, so why don;t you *read* it?
Water has a thermal IR emissivity of 0.98, about as black as anything
gets.
John
- posted
15 years ago
Cheap thermometer calibration technique?
Loading thread data ...
- posted
15 years ago
Nothing like a little actual data to cut through the fog...
or a little confirmation from them that depends on this stuff for their income...
Or an oft-referenced expert source.
Thanks again, John. Dave (OP)
or a little confirmation from them that depends on this stuff for their income...
Or an oft-referenced expert source.
Thanks again, John. Dave (OP)
- posted
15 years ago
Can you really be that dumb?
If the instrument has a one inch focus, your reflection is hardly going to affect what it reads from the face of a "shiny piece of copper". It will read the copper, and be off be the emissivity factor.
Focus is extremely important in the energy gathered by an IR instrument. EXTREMELY. Do you think the 1000' focus device looking at the space shuttle launch pad would get enough energy to give a calibrated reading if it were focused for 20 feet, despite being 1000' away from the target being measured?
Use some common sense, man.
If the instrument has a one inch focus, your reflection is hardly going to affect what it reads from the face of a "shiny piece of copper". It will read the copper, and be off be the emissivity factor.
Focus is extremely important in the energy gathered by an IR instrument. EXTREMELY. Do you think the 1000' focus device looking at the space shuttle launch pad would get enough energy to give a calibrated reading if it were focused for 20 feet, despite being 1000' away from the target being measured?
Use some common sense, man.
- posted
15 years ago
You're an idiot, and there are NO 1.0 emissivity sources.
I think you need to re-learn what is in the realm of possibility. Try the PDF I posted a link to for starters.
I think you need to re-learn what is in the realm of possibility. Try the PDF I posted a link to for starters.
- posted
15 years ago
It isn't the gradient across it, it is what it inhibits THROUGH it. It
does have good surface quality for high emissivity, however.I merely
stated that there would be losses.
- posted
15 years ago
Yes.It was me, and a MATTE finish (flat black paint) WILL yield a BETTER
surface quality with reference to IR readings than a shiny surface will.
- posted
15 years ago
List all the 1.0 emissivity sources you know of.
- posted
15 years ago
The expert source would certainly NOT be john, and the link was from
ME, asshole.
- posted
15 years ago
Well read it then. Water is 0.98.
John
John
- posted
15 years ago
Use a melting ice cube for zero C, and boiling distilled water (in a
clean container) for 100 C.
- posted
15 years ago
What part of "close to" do you not understand?
robert
robert
- posted
15 years ago
[...]
Are you illiterate? Why don't you look up water in the data YOU provide and see for yourself how shiny it is? Hint 0.98 isn't shiny. 0.98 is about as black as it gets.
robert
Are you illiterate? Why don't you look up water in the data YOU provide and see for yourself how shiny it is? Hint 0.98 isn't shiny. 0.98 is about as black as it gets.
robert
- posted
15 years ago
In the chart the link to which YOU keep posting here, nothing has a higher
emissivity than water.
Which makes water an extremely good choice for a reading on the IR instrument.
robert
Which makes water an extremely good choice for a reading on the IR instrument.
robert
- posted
15 years ago
I agree that illiteracy combined with extreme stupidity is a tough burden to
carry.
robert
robert
- posted
15 years ago
formatting link
It shows ice/water having a very high emissivity.
- posted
15 years ago
No, it wouldn't because it is four times more expensive, and it's
electrical conductivity and its thermal conductivity are not the same,
asswipe.
Alumininum is he right medium conduction wise, AND it is the right medium cost wise. The coating on eother would yield the same result so any point you thought you were making is moot.
You need to get off you "fuck with dark matter" high horse, and get back to reality, boy.
The KeithTard, and the Grisetard can't fuck with me, so what makes you think you can, dipshit?
Alumininum is he right medium conduction wise, AND it is the right medium cost wise. The coating on eother would yield the same result so any point you thought you were making is moot.
You need to get off you "fuck with dark matter" high horse, and get back to reality, boy.
The KeithTard, and the Grisetard can't fuck with me, so what makes you think you can, dipshit?
- posted
15 years ago
absolutely the wrong choice though. It is unstable, and gives off
vapors, throwing off surface conditions, which is what an imager MUST
focus on to get reliable calibration data.
- posted
15 years ago
Why do you even bother reading his posts? He is wrong far more often
than right and never admits an error.
- posted
15 years ago
Actually, the international standard is a bunch ice covered in water a
stirred well. The standard clearly says that this must be done in
your own coffee cup and the stirring must be done with a plastic
coffee stirrer. You have to stir it up while standing in the company
kitchen and then measure as soon as you are done stirring. You can't
stop to answer the "What the heck are you doing?" question from the
cute accountant.
- posted
15 years ago
Did you miss the word "almost"? 3rd line, 2nd word in my paragraph
above.
With an imager, it takes a few seconds to test a surface to get a pretty good idea of its emissivity. The whiteboard marker, and the water, and the ice cube, all passed my tests for "so black that it doesn't matter", or, equivalently, "almost 1.0"
I read it; you didn't.
John
With an imager, it takes a few seconds to test a surface to get a pretty good idea of its emissivity. The whiteboard marker, and the water, and the ice cube, all passed my tests for "so black that it doesn't matter", or, equivalently, "almost 1.0"
I read it; you didn't.
John