In this directory contains some information of the "xop2.4" package. See information on xop 2.4 and downloading instructions at: https://www1.aps.anl.gov/Science/Scientific-Software/XOP xop2.4 is embedded with idl8.3 and is subject to U.S. Export Control and is categorized under Export Control Classification Number (ECCN) 5D002. To use it you need to complete and submit the "Software Application Form for XOP v2.4 and Future Releases" as instructed in the aforementioned web site. If all export requirements are met the software will be distributed to the applicant. The user will then receive the instructions and passwords to download and install the software. Once installed xop 2.4, the xop "extensions" are downloaded from other web sites. In particular: - shadowvui can be downloaded from this site: http://ftp.esrf.fr/pub/scisoft/xop2.4/ - imd and topo can be downloaded from David Windt site: http://www.rxollc.com/idl/ The previous version xop2.3 is not subject to the Export Control and has similar functionality. It has been embedded using IDL 7.0 (2007) so there are some problems running new OS (e.g., Apple Yosemite). It can be downloaded freely from: - http://ftp.esrf.eu/pub/scisoft/xop2.3/ Users are strongly advided to register and use xop2.4. We will maintain xop2.3 updated as far as possible but there is not installation and debugging support. The xop developers: M Sanchez del Rio (srio@esrf.eu) and R J Dejus (dejus@aps.anl.gov)