FLIR T6xx series, Руководство пользователя

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Working with measurement tools 17
5.
Push the joystick. This will display a dialog box where you can select the measure-
ment tools that you want to use in the difference calculation.
6. Push the joystick. The result of the difference calculation is now displayed in the re-
sult table.
17.6 Changing object parameters
17.6.1 General
For accurate measurements, you must set the object parameters.
17.6.2 Types of parameters
The camera can use these object parameters:
• Emissivity , i.e., how much radiation an object emits, compared with the radiation of a
theoretical reference object of the same temperature (called a “blackbody”). The op-
posite of emissivity is reflectivity. The emissivity determines how much of the radiation
originates from the object as opposed to being reflected by it.
• Reflected apparent temperature , which is used when compensating for the radiation
from the surroundings reflected by the object into the camera. This property of the ob-
ject is called reflectivity.
• Object distance , i.e., the distance between the camera and the object of interest.
• Atmospheric temperature , i.e., the temperature of the air between the camera and the
object of interest.
• Relative humidity , i.e., the relative humidity of the air between the camera and the ob-
ject of interest.
• External IR window compensation , i.e., the temperature of any protective windows,
etc., that are set up between the camera and the object of interest. If no protective
window or protective shield is used, this value is irrelevant and should be left inactive.
17.6.3 Recommended values
If you are unsure about the values, the following are recommended:
Emissivity 0.95
Object distance 1.0 m (3.3 ft.)
Reflected apparent temperature +20°C (+69°F)
Relative humidity 50%
Atmospheric temperature +20°C (+69°F)
17.6.4 Procedure
Follow this procedure:
1. Push or tap the screen to display the menu system.
2. Use the joystick to go to .
3. Push the joystick to display a dialog box.
4. Use the joystick to select and change an object parameter.
5. Push the joystick. This will close the dialog box.
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