There are three intercept methods which count and measure the intercepts of a reference line with the detected grain boundaries. The Grain Size value is then calculated according to the expression defined in the standard. Each method uses different definition of the reference line (measurement mask).
Number of circles
Minimal diameter
Maximal diameter
Vertical and horizontal lines length
Diagonal lines length
Small circle diameter
Medium circle diameter
Large circle diameter
The reference lines may be horizontal, vertical or both. The number of lines in each direction or the distance between the lines must be set. Clipping Rectangle defines the area of interest that reference lines don´t exceed.
Figure 430. Linear method options
Figure 431.
The following parameters must be set:
Figure 432. Options - Circular Method
Figure 433.
The following parameters must be set:
Figure 434. Options - Abrams Method
Figure 435.
Special measurement is possible by the intercept methods, when the operator (for any reason) decides to skip detection and to make all intersections completely manually. Even in this case the detection preset must exist and must contain “full range thresholding histogram” covering the whole field.
Note
When the measurement starts while the 
Show Mask button is pressed, the mask overlaps the intercepts so the coloring is not visible properly. Switch off the button to see the intercepts only, not the mask.
See also Measurement Mask.