In this page, you will find all the manuals needed to prepare and analyse your observations with FORS2. Please be sure to download the manual corresponding to the period in which the observations will take place.

All the manuals are in Adobe's Acrobat format.

  • FORS2 User Manuals
    All the information about the instrument itself, its modes and their characteristics is provided in the FORS2 User Manual (UM): 
    • 1) valid for Phase 2 for P101 (period starting April 2018): Period 101.1  (very minor changes from CfP P101 UM)
    • 2) valid for the current semester (01/10/17 to 31/03/18): Period 100
  • FORS2 Template User Manual
    Detailed information on the acquisition, observation, and calibration templates:
    • Period 92 for observations during the current and next periods.
  • FORS2 FIMS User Manual
    Detailed information on the Instrumental Mask Simulator software tool to prepare precise target acquisitions at Phase 2:
    • Period 92, for observations during the current and next periods.
  • FORS1+2 data reduction Pipeline
    The various pipeline recipes to reduce FORS data are available here.
  • Science Data Product Forum
  • REFLEX Tutorial
    Tutorial reflex workflows for FORS2 can be found on the VLT pipeline page here.
  • Data reduction frequently asked questions
    A list of Frequently Asked Questions on data reduction is also available.
  • FORS2 Absolute Photometry Project
    Detailed information on the FORS Absolute Photometry (FAP) project, whose goal is to produce a 3% absolute photometric accuracy,
    if nights are photometric (see Freudling et al., 2006).

           Nightly zeropoints and extinction coefficients are available at 
           and the description of the table entries and definitions can be found at
           Due to the method used, the nightly zeropoints become available with a delay of about 4 weeks.

  • Historical FORS1+FORS2 User Manual
    The Period 82 version of the User Manual contains information on FORS1 and FORS2 prior to the merger of the two instruments in 2008.