SICK Ranger3

Scatter dynamic range tuning
The Ranger3 camera has built-in configurable dynamic range reduction from 16 to 8
bits. The dynamic range reduction reduces the bandwidth of the camera and adjusts
the contrast of the scattering data.
When reducing the dynamic range, the first step is an initial tuning to set the following
parameter values:
•
ScatterReductionLowerLimit: The signal level to map to dark (value = 0)
•
ScatterReductionUpperLimit: The signal level to map to bright (value = 255)
Between the set limits, the signal level is estimated by a linear model or by a non-linear
model with one or two knee-points. The non-linear models allow approximation of the
gamma correction curve, which mimics the manner in which humans perceive light and
color. The knee-points are set as a percentage of the signal range.
figure 29 illustrates the input to output conversion for different dynamic range reduc‐
tion models. The two-knee model gives the most accurate approximation of the gamma
correction curve.
0
500 1000 1500 2000 2500 3000 3500
Input 2
Output 1
50
100
150
200
250
Figure 29: Illustration of input (horizontal axis) to output (vertical axis) conversion using 16 to
8-bit dynamic range reduction. The input signal is mapped to 0-255. A linear model (blue),
a non-linear model with one knee-point (green) and a non-linear model with two knee-points
(black) are used to approximate a gamma correction curve with gamma = 0.7 (red)
1
Output
2
Input
8.9 High dynamic range (HDR) imaging
Ranger3 supports high dynamic range (HDR) imaging, which increases the sensor's
ability to adequately reproduce both bright and dark areas in a scene. HDR is suitable
for improving the localization of the laser line when acquiring images containing both
dark and bright materials, such as bright objects towards a dark background or dark
objects with bright prints.
Figure 30: Acquisition of
profiles
Figure 31: Resulting profile,
linear (non-HDR) mode
Figure 32: Resulting profile,
HDR mode
CONFIGURATION 8
8020774/1D7Q/2022-03 | SICK O P E R A T I N G I N S T R U C T I O N S | Ranger3
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Subject to change without notice