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How to Measure Colors

Main Tab

1. In the Step Name control, enter a descriptive name for the step.
2. Choose one of the following methods to specify the region of interest for the step:
   • Create a new region of interest.
     1. Select Constant from the Region of Interest listbox.
     2. Select a tool from the menu toolbar that matches the type of region of interest you want to specify.
     3. Draw a region of interest on the image.
   • Select a previously defined region of interest from the Region of Interest listbox.
3. Verify that the Reposition Region of Interest option is enabled if you want to link the region of interest specified in this step to a previously defined coordinate system.

   Link the region of interest to a coordinate system if the position of the object under inspection changes from image to image, and you need to adjust the position of the region of interest to match the new location of the object.

Histogram Tab

4. Select the Color Space of interest for making the color measurements.
5. If you are using the CIE L*a*b* color space, enter the white reference values you want to use for calculating the color measurements.

Limits Tab

6. Select the criteria you want to use to verify the presence or absence of a feature, and set appropriate Minimum and Maximum values for the criteria.

   Note  Pixel intensities may vary significantly from image to image depending on lighting conditions and object surface aspects. Check the validity of the parameters defined in the Limits tab to discern good and bad parts by using an image set representative of typical process fluctuations.