Opticsbuilder: build Synrad optics from sequence === [Opticsbuilder downloads](https://molflow.web.cern.ch/content/opticsbuilder-downloads) # Adding elements First fill names and lengths:  Add physical parameters:  Set reference point by selecting a line (the first in this example), this is important as it will calculate element positions:   The grey fields show the calculated element positions:  # Adding lattice functions They are required for a Synrad simulation (ideal beam not supported)  They are in meters, they must be positive. # Saving session Opticsbuilder has a session manager, allowing you to save/load your work.  # Writing lattice functions file (.bxy) First you have to write a BXY file, to be loaded by Synrad's `.param` files.  # Writing Synrad regions (.param and .mag)  # Opening in Synrad Use the Regions/Load command...  you can select all files at once:  Synrad will load the magnetic regions.