FLIR EX Series, Руководство пользователя

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Operation 7
5. In the dialog box, select Custom material . This displays a list of materials with known
emissivities.
6. In the list, select the material.
7.17 Changing the emissivity as a custom value
7.17.1 General
For very precise measurements, you may need to set the emissivity, instead of selecting
a surface property or a custom material. You also need to understand how emissivity and
reflectivity 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 reflected.
Polished stainless steel, for example, has an emissivity of 0.14, while a structured PVC
floor typically has an emissivity of 0.93.
For more information about emissivity, see section 15 Thermographic measurement
techniques , page 50.
7.17.2 Procedure
Follow this procedure:
1. Push the center of the navigation pad. This displays a toolbar.
2. On the toolbar, select Settings . This displays a dialog box.
3. In the dialog box, select Measurement parameters . This displays a dialog box.
4. In the dialog box, select Emissivity . This displays a dialog box.
5. In the dialog box, select Custom value . This displays a dialog box where you can set
a custom value.
7.18 Changing the reflected apparent temperature
7.18.1 General
This parameter is used to compensate for the radiation reflected by the object. If the
emissivity is low and the object temperature significantly different from that of the re-
flected temperature, it will be important to set and compensate for the reflected apparent
temperature correctly.
For more information about reflected apparent temperature, see section 15 Thermo-
graphic measurement techniques , page 50.
7.18.2 Procedure
Follow this procedure:
1. Push the center of the navigation pad. This displays a toolbar.
2. On the toolbar, select Settings . This displays a dialog box.
3. In the dialog box, select Measurement parameters . This displays a dialog box.
4. In the dialog box, select Reflected apparent temperature . This displays a dialog box
where you can set a value.
7.19 Changing the distance between the object and the camera
7.19.1 General
To measure temperatures accurately, the camera requires the distance between the
camera and the object.
7.19.2 Procedure
Follow this procedure:
1. Push the center of the navigation pad. This displays a toolbar.
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