Annotation labels can optionally include minimum and maximum values that specify the zoom range within which the label will be visible. These values are added using 'ZMIN' and 'ZMAX' in the annotations.xml file. In this example, there is a yellow circle directly centered in the image which is only visible at 100% zoom. There are also two polygons which are visible when partially zoomed in. The captions of the labels have been set to describe the zoom min and max values assigned. For more information on using the ZMIN and ZMAX values, see the Parameter List in the Documentation folder.