Achieving a good image14
14.7 Performing a non-uniformity correction
(NUC)
14.7.1 General
When the thermal camera displays Calibrating... it is performing what in thermography is
called a ”non-uniformity correction” (NUC). An NUC is an image correction carried out by
the camera software to compensate for different sensitivities of detector elements and oth-
er optical and geometrical disturbances
6
. For more information, see section 34 About cali-
bration, page 283.
An NUC is performed automatically, for example at start-up, when changing a measure-
ment range, or when the environment temperature changes.
You can also perform an NUC manually. This is useful when you have to perform a critical
measurement with as little image disturbance as possible. You may, for example, want to
perform a manual calibration just before you start recording a video sequence.
14.7.2 Performing an NUC manually
14.7.2.1 Procedure
Follow this procedure:
1. To perform a manual NUC, push and hold down the image archive button
for
more than 2 seconds.
Note You can also assign the function Calibrate to the programmable button
. For
more information, see section 11.12 Assigning functions to the programmable button,
page 38.
14.8 Hiding all overlay
14.8.1 General
The camera overlay consists of overlay graphics and image overlay information. The over-
lay graphics include items such as measurement tool symbols, result tables, and status
icons. The image overlay information, which you activate on the Settings menu, provides
additional information such as the date, emissivity, and atmospheric temperature. For
more information, see section 9.5 Image overlay information, page 25.
You can choose to hide all camera overlay by pressing the programmable button
.
#T810190; r. AL/47698/47698; en-US
70
6. Definition from the European standard EN 16714-3:2016, Non-destructive Testing—Thermographic Testing—
Part 3: Terms and Definitions.