# Overview

The Caliper tool differs from other vision tools in that it requires that you know the approximate location and characteristics of the feature or edges you want to measure or locate.

The Caliper tool is typically used to develop detailed information about the precise locations of features within an object. It is not appropriate for developing information about the shape of objects or features.

The Caliper tool locates edges or edge pairs in an image using the edge mode method, in which edge peaks are detected using a simple 1-D kernel

Once you have determined the location and orientation of the edge or edge pair of interest within the image, you perform the following steps to apply the Caliper tool:

- Specify a projection region that encloses the edges or edge pairs of interest.
- Select a filter size and contrast threshold that isolate the edges of interest.
- Define an edge model that describes the edge or edge pair of interest.
- Define the scoring methods that are used to score edge pattern candidates within the image.
- Apply the Caliper tool and interpret the results.