M310-HT Manual Appendix A: Calibration & Emissivity • 21
Example 1: The M310HT (450 °C) blackbody was factory calibrated to provide effective
emissivity = 1.0 at 8-14 µm. You wish to use this source for a narrow band pyrometer at 7.5 µm.
At this wavelength from the graph above, the blackbody exit radiance will be approximately
equivalent to a blackbody that has emissivity = 1.011. This will cause your pyrometer to receive
1.1% more infrared energy causing it to read a higher temperature. The table below shows the
expected error. At 250 °C, this pyrometer will read 251.4 °C or 1.4 °C high, so you should set the
blackbody setpoint to 248.6 °C (250-1.4).