Distance Annotation
The Distance Measurement Annotation is used to calculate the length a single linear measurement. Once placed measurements can be modified by dragging any of the vertices on the measurement and the values will be updated as well.
Creating a Distance Measurement
- Select the Distance tool by clicking the
in the Comment Tab on the toolbar or using the shortcut key Ctrl + Alt + M (⌘ + Alt + M on Mac) - The measurement dialog will be displayed where you can set the scale and precision (and calibrate if needed) for the measurement prior to drawing the annotation.
- Click where you would like the measurement to begin and then move the cursor where you would like the measurement to end and click again to place the measurement on the page (Note: Hold the Shift key while drawing to make horizontal, vertical, or 45 degree angle lines.)
Measurement Options
The following options can be set before the measurement is created.
Scale
Options to set the scale and precision (and calibrate if needed) for the measurement prior to drawing the annotation. By default the horizontal and vertical scale will be the same.
Check the "Separate Vertical Scale" option to specify a different vertical scale for the measurement.
Other
Snap to Content - each point of the measurement will automatically attempt to snap to the nearest content item when clicked
Display Measurements - show / hide the measurement label on the measurement line
Always used fixed angles (shift key) - forces all measurements to make horizontal, vertical, or 45 degree angle lines only
Annotation Properties
To access the Distance properties go to the Properties Tab on the toolbar or right click (Mac: Ctrl + Click) on the annotation and choose Properties in the mouse menu or click on the edit button 
on the Mini Toolbar. The Distance measurement contains the following property settings.
Appearance
Line Width - Sets the width of the line
Line Start - Sets the shape to be used at the beginning of the line
Style - Sets the style for the line (i.e. dotted, dashed, cloud, etc...)
Line End - Sets the shape to be used at the end of the line
Color - Sets the color of the line
Fill Color - Sets the fill color of the shapes at the end of the line
Transparency - Sets the transparency of the measurement
Length - The current length of the measurement annotation. Can be manually edited if needed to set a specific value and will adjust the annotation on the page accordingly.
Note / Comment - a comment field that allows you to add an additional comment to the measurement if needed
Save as default - When checked this will make the selected appearance settings the default for any new Distance annotations going forward
Locked - When checked prevents the following on the annotation: being moved or resized, editing appearance properties, & deleting the annotation.
General
Author - Allows you to edit the author
Subject - Allows you to edit the subject
Layer - Only available when the document contains layers. Sets the layer that the annotation belongs to. For more information see Assigning Comments to Layers
Status History
This tab will display and changes to the review status of the annotation including Author, Status, and Timestamp. For more details see Setting Status or Check Marks on Annotations