User's Manual

Achieving a good image13
13.7 Performing a non-uniformity correction
(NUC)
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
other optical and geometrical disturbances
1
. For more information, see section 32 About
calibration, page 187.
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.
13.7.1 Performing an NUC manually
13.7.1.1 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 10.12 Assigning functions to the programmable button,
page 34.
13.8 Hiding all overlay
13.8.1 General
The camera overlay consists of overlay graphics and image overlay information. The
overlay 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 tempera-
ture. For more information, see section 8.5 Image overlay information, page 22.
You can choose to hide all camera overlay by pressing the programmable button
.
Image with camera overlay and image overlay
information.
Image with all overlay hidden.
#T810190; r. AB/39747/39747; en-US
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1. Definition from the European standard EN 16714-3:2016, Non-destructive Testing—Thermographic Testing—
Part 3: Terms and Definitions.