Both are about 2:1 better than aluminum. The factor is even higher
compared to common aluminum alloys; hardly anybody wants to machine
pure aluminum, and the alloying wrecks both the electrical and thermal
You fuck with yourself. Or job is to laugh.
On May 9, 7:56 am, John Larkin
In all metals, the thermal and electrical conductivity track each
other quite nicely. Copper alloys such as brass are way less
conductive. The atomic clock folks use a copper alloy that is very
resistive to make heaters.
Hhat can I say but WrongAgain?
Look into a mirror that's reflecting the sky into your eyes. You see
the color of the sky. Now take off your glasses or equivalent to
defocus the scene. You still see the color of the sky.
If defocussing means you are averaging unwanted objects into the image
with the desired target, sure you need to focus. But no amount of
focussing, from any distance, will make the emissivity of shiny copper
any better, or improve the temperature measuring accurscy.
If you poke the germanium lens one inch away from the copper, and
focus perfectly, you'll be measuring mostly the reflection, namely the
temperature of the lens itself, not the temp of the copper. Try it.
OK, common sense: look in a mirror. You see your face, not the mirror.
Get closer; you still see your face, not the mirror.
I mentioned the flat side because I wanted the sensors to be close to,
and so at the same temperature, as the surface. The fins could easily
be at a different average temperature.
Thanks for the interesting link. I note that it shows a very common,
inexpensive material, black cloth, with an uncommonly high emissivity:
0.98. With this information, I'd change my suggestion to using a
flattish copper block (highest possible thermal conductivity) of a
size to take up the viewing area of the IR meter, holes and sensors as
before, and with a piece of black cloth glued to the surface. I think
the whole thing would be inexpensive and fairly accurate.
You don't get it. If the surface (read that word carefully, idiot) is
prepared correctly, a 0.98 emissivity is achieved, and AL makes an
EXCELLENT black body source, and it is used in the industry EVERY DAY.
So fuck off, you goddamned retard.
Similar to imagery. One should always take the highest resolution shot
possible, so that it can be used in any circumstance form a low res paste
to a hi res utilization.
Calibrating an instrument should always involve a known source that is
of a HIGHER resolution that the instrument itself is.
If a source that equals the instrument's accuracy is used the error
level in the two can chain together. In fact, it is termed as "chaining
It wasn't for me personally. I was concerned about anyone who may not
have seen his posts before. Since he seems to specialize in lame
insults and counterfactual statements, I don't read his posts much
anymore. When someone replies to him, I may read the reply. Someone
new to the group, however, may not know this about him.
One of the local news groups I used to frequent had a monthly FAQ
posting. There was an unoffical "keeper of the FAQ" who would edit it
from time to time and post it about once a month unless it was raining
or too sunny that week.
It worked moderately well. From time to time a newby would jump in
with a post before reading it and get gently roasted over the open
flames. When spam ads were posted we would have a little competition
to see who could write the best parody of it.
You really need a set of temperature standards. Temperature standard
equipment is expensive.
On a laser temperature reader, there is the EMS "emisivity) factor.
You must set the EMS of the reader to be proper for the type of object
you are measuring. If the EMS is not adjustable on your reader, then
the reference object must be of the correct colour and type of
material to be referenced.
If your reader is expensive to replace, I would suggest you send it to
a calibration lab that can check these types of units.
A crude way of checking the temperature accuracy is to use ice water
with crushed ice, and measure the water. This should read within about
0.5 C under ideal conditions. You can boil some water, but the
borametric pressure facture must be considered. This should be able to
reference to within about 0.5 C. The water must be purified water.
Tap water will have minerals in it, and its boiling point will be