Set Zoom Level
Enlarges or reduces the image on the screen.
Set Zoom Level [Lock; 25%...400%/Zoom In/Zoom Out]
Lock prohibits users from making changes to the zoom level.
Specify lets you select a zoom level.
Reduction values: 100%, 75%, 50%, or 25%.
Enlargement values: 150%, 200%, 300%, or 400%.
Zoom In reduces the screen image by one zoom level.
Zoom Out enlarges the screen image by one zoom level.
This script step is:
Originated in 
FileMaker Pro 6.0 or earlier
Go to Layout ["Data entry"]
Set Zoom Level [Lock; 100%]
Related topics 
Script steps reference (alphabetical list)
Script steps reference (category list)