Rockwell Automation 5370-CVIM2 Module - Manual (Page 410)

Chapter 7
Inspection Tools
7–172
Min+%Diff High Mode
When you pick Min+%Diff High in the Thresh Mode panel, the Threshold
panel appears as shown in Figure 7.138.
Figure 7.138 Appearance of Threshold Adjustment Panel With Min+%Diff High Mode
In this mode, the slide bar has two cursors (the % and High cursors) and two
corresponding fields (the % and Limit fields). The default value for the “ % ”
field is 50, and the default value for the “ Limit ” field is 255.
The Min+%Diff High threshold mode enables you to set up a dynamic
threshold, along with a maximum limit above which the threshold may not go
during run mode operation.
The concept of the Min+%Diff High threshold mode is this: The profile tool
will find the minimum and maximum gray scale values on the profile display,
and then place the threshold at a position that is equal to the minimum value
plus 50% (default value) of the difference between the minimum and
maximum values, not to exceed an upper limit of 255 (default value).
The practical effect is this: During run mode operation, the threshold will
automatically readjust itself whenever lighting and other external
circumstances change, but it will not exceed the high limit value.