THELI v2 is no longer supported as of February 2018, as the code base is very outdated and faces increasing installation difficulties. A complete rewrite, THELI v3, is available from https://github.com/schirmermischa/THELI. It offers numerous and vast improvements. While still being undocumented, users familiar with v2 will find it easy to switch to v3. For any questions please contact schirmer[at]mpia.de .

THELI GUI (outdated)

Last update:Mar 23, 2018
Latest changes:ChangeLog

THELI is a powerful and easy-to-use package for astronomical image reduction, offering e.g.

  • Automated reduction of optical, NIR and MIR data
  • 90 pre-configured instruments
  • Parallelisation
  • Flexible background correction
  • Automatic distortion correction and creation of large mosaics
  • Highly flexible coaddition: e.g. locking onto proper motion targets, various projections, etc
  • Optimised weighting schemes and defect detection
  • Crosstalk and non-linearity correction
  • Atmospheric transparency correction
  • Absolute flux calibration
  • Extensive documentation and online help



Please cite the following two papers when publishing your scientific work based on THELI:

  • Schirmer M. 2013, ApJS, 209, 21: THELI GUI – Convenient reduction of optical, near- and mid-infrared imaging data
  • Erben, T., Schirmer, M., Dietrich, J. et al. 2005, AN, 326, 432: GaBoDS: The Garching-Bonn Deep Survey. IV. Methods for the image reduction of multi-chip cameras demonstrated on data from the ESO Wide-Field Imager