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72 WFS Series
It is recommended to check the actual saturation degree of the camera's AD
converter by verification on the LineView panel.
Attention
Manual settings of 'Exposure time' and 'Master gain' must not lead
neither to image saturations (pixel intensity = 255 digits) nor to
low image brightness (max. intensity < half range 128 digits).
Otherwise, measurement errors and noise will increase.
Noise Cut Level
'Noise cut level' defines a brightness level in digits which needs to be exceeded by
the spots. Ambient light and noise terms below this limit will be set to zero intensity.
See the result in the Lineview panel. Since defining such a fix level is problematic for
changing beam intensities and ambient light situations, the 'Auto' setting is highly
recommended which enables dynamic adaption to the different intensity levels for
each spot area and yields best results for centroid calculation.
For a manual definition of the noise cut level, values between 0 and 255 digits may
be applied.
Attention
Improper settings of manual 'Noise Cut Level'
may lead to increased measurement errors.
Black Level
'Black Level' is a camera setting that adjusts the offset brightness level for all
illuminated pixels and should be adjusted so that the minimum line in the Lineview
panel is to be seen above zero. In case of very high noise level reduce the setting.
"Arbitrary Unit" (a.u.) values range from 0 to 255.
Examples (WFS):
Black Level = 255 is too high, lowest intensity pixels (lower curve) showing high
offset.