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Emissivity
thermoMETER CT
14.3 Characteristic Emissivity
In the case that none of the methods mentioned above help to determine the emissivity you may use the
emissivity tables, see A 3, see A 4. These are only average values. The actual emissivity of a material de-
pends on the following factors:
- Temperature
- Measuring angle
- Geometry of the surface (smooth, convex, concave)
- Thickness of the material
- Constitution of the surface (polished, oxidized, rough, sandblast)
- Spectral range of the measurement
- Transmissivity (e.g. with thin films)