Figure 10: Camera Mounted On Tripod; Figure 11: Camera Schematic Showing Flux Contribution: Red = Internal Housing Contribution, Green = Useful Ir Flux Part Coming From The Scene Through The Lens - Teledyne FLIR A68 Series User Manual

To the extent possible, the camera, while thermally connected to the
system/environment, should be insulated from rapid temperature swings and changes
in airflow. Extreme thermal shock reduces the effectiveness of calibration and degrades
the quality of the image and the accuracy of the reading. For example, if the camera is
only mounted on a tripod the ambient temperature change will influence the complete
camera thermal behavior leading to a less accurate temperature reading.

Figure 10: Camera Mounted on Tripod

Figure 11: Camera Schematic Showing Flux Contribution: Red = internal housing contribution, Green =
useful IR flux part coming from the scene through the lens
Signal coming from the red part (camera internal housing) in the above schematic
represents pollution that must be subtracted from the image for proper temperature
measurements. This process is (generally) handled by the camera's shutterless Non-
Uniformity Correction (NUC) mechanism.
FLIR A68/A38 Series IR Camera User's Manual Features and Configuration Options • 47