To create a Vision Circle:
For machines supporting DCC
motion, select DCC Mode 
if you want to create and measure circles in DCC mode.
Select Auto
Circle 
from the Auto Feature toolbar. You can also
select the Insert | Feature | Auto | Circle
menu option. This opens the Auto Feature
(circle) dialog box.
Vision Circle Auto Feature dialog box
With the Auto Feature dialog box open, select a circle in one of two ways:
CAD Selection Method - From the CAD tab, click once near the edge of the circle on the CAD surface to establish the circle's location.
Target Selection Method - From the Vision tab, click to add three points around the circle; or double click to automatically add three points equally spaced around the circumference of the visible circle. This establishes the circle's location. Adjust the lighting and magnification as needed.
Click as close as possible to the CAD element to ensure PC-DMIS does not choose an incorrect element.
PC-DMIS Vision automatically places the nominal data for the circle into the Auto Feature dialog box. The hit targets will automatically be displayed for the circle.
Adjust the nominal information in the Auto Feature dialog box to match the theoretical values of the circle. Also, adjust the values of the Probe Toolbox as needed.
Click Test to test circle measurement.
Click Create on the Auto Feature dialog box to add the circle to the measurement routine.
Save the measurement routine for future execution. See "A Note on Executing a Vision Measurement Routine".