11.15
Changing the emissivity
General
For very precise measurements, you may need to set the emissivity, instead of se-
lecting a surface property. You also need to understand how emissivity and reflectiv-
ity affect measurements, rather than just simply selecting a surface property.
Emissivity is a property that indicates how much radiation originates from an object
as opposed to being reflected by it. A lower value indicates that a larger proportion
is being reflected, while a high value indicates that a lower proportion is being reflect-
ed.
Polished stainless steel, for example, has an emissivity of 0.14, while a structured
PVC floor typically has an emissivity of 0.93.
Procedure
Follow this procedure to set the emissivity:
Push the left selection button (
Menu
).
1
Use the navigation pad to go to
Measure
.
2
Push the left selection button (
Select
). This will display the
Measure
sub-
menu.
3
Use the navigation pad to select
Advanced
.
4
Push the left selection button (
Select
). This will display the
Advanced
sub-
menu.
5
Use the navigation pad to do either of the following:
■
Set a value for emissivity
■
Select a material in the list of materials
6
Push the left selection button (
Select
) to confirm the choice and leave the
menu.
7
SEE ALSO
To read more about emissivity, see section 20 – Thermographic measurement tech-
niques on page 127.
Publ. No. T559382 Rev. a358 – ENGLISH (EN) – June 23, 2009
31
11 – Using the camera
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