You are here

Gemini IRAF Data Reduction Software

Content owned by aadamson


The Gemini IRAF package is a data reduction software package for processing observational data obtained with the Gemini telescopes. The released version of the Gemini IRAF package is an external package layered upon IRAF and is available to users and other interested parties.

The Gemini IRAF package is being phased out in favor of DRAGONS.  However, there are still some instruments and modes that are not yet supported in DRAGONS.  For those, Gemini IRAF is required.

The Gemini IRAF package must be used for the following instruments and modes:

  • FLAMINGOS-2 longslit and MOS
  • GMOS-N and GMOS-S MOS and IFU
  • GNIRS longslit, cross-dispersed and IFU
  • Decommisionned instruments/modes:
    • NIFS
    • NIRI longslit
    • Michelle
    • TReCS
    • OSCIR
    • Hokupa'a+QUIRC
    • Flamingos-1. 

The Gemini IRAF package is organized into a number of sub-packages named after the instrument they support. It contains a generic tools package, "gemtools", along with instrument-specific packages. The raw data from the Gemini facility instruments are stored as Multi-Extension FITS (MEF) files. Therefore, all the tasks in the Gemini IRAF package, intended for processing data from the Gemini facility instruments, are capable of handling MEF files.

  • Stable Version: v1.16
  • Revision note: gemini_v116_rev.txt
  • Version 1.16 includes new support for GNIRS IFU low-resolution.

System Requirements

  • Python 3.7 to 3.10 
  • 32-bit compatibility libraries
  • Linux, equivalent to CentOS 7 and above
  • Or very old Mac OS X 10.13 to 10.14.0
  • Miniforge or Anaconda
  • For modern Mac OS, the use of a VM is required.
    • The US-NGO will be issuing a 64-bit version of this package at some point that will remove the need for the VM.  Contact them. Disclaimer: That software is not tested by Gemini data reduction people.


Important - Mac Users: If you are working on Mac OS, you will need to use a virtual machine (VM) for your Gemini IRAF work.  See for instructions and installation help. Once you have the VM running, go to the Set the Conda Channels section, followed by the Updating Gemini IRAF section.

For Linux, continue.

Installing Miniforge

Miniforge (or Anaconda) is recommended for easy IRAF, Gemini IRAF, and PyRAF installation. If you do not already have a conda distribution system installed, see the Miniforge installation instructions from the DRAGONS documentation.

Set the Conda Channels

Edit the ~/.condarc file to have the following channels, in that order:

      - conda-forge

Installing Gemini IRAF

The next step is to create a virtual environment and install the Gemini IRAF package and its dependencies.  Conda will take care of installing the dependencies.  The name of the environment can be anything you like. Here we use “geminiconda” as the name. 

    $ conda create -n geminiconda python=3.10 gemini iraf-all pyraf-all ds9

To use this environment, activate it:

    $ conda activate geminiconda

You will need to activate the environment whenever you start a new shell. If you are planning to use it all the time, you might want to add the command to your .bash_profile, after the “conda init” block.

Updating Gemini IRAF

If you already have Gemini IRAF installed and wish to update the package to version 1.16, run the following commands:

    $ conda activate geminiconda
    $ conda install iraf.gemini=1.16 --no-update-deps

Configuration and Testing

Configuring IRAF

If you have installed IRAF and PyRAF and need to use Gemini IRAF, make sure that there is a configured iraf directory in your home directory. If you have used IRAF before it might already be there, it might still be wise to re-run the mkiraf step. To set up a new IRAF directory:

    $ cd ~
    $ mkdir iraf
    $ cd iraf
    $ mkiraf

At the mkiraf step, choose xterm or xgterm for the terminal, and re-initialize the uparm when/if asked.

Your computer might require 32-bit compatibility libraries. 

Testing the installation

Test Gemini IRAF
        $ conda activate geminiconda
        $ pyraf
        --> gemini

You should be seeing the Gemini IRAF packages for each instrument.


For help running IRAF on Gemini instruments, see Getting Started with Gemini IRAF.


If for some reason you need the tar file for v1.16 instead of using the conda package, you can download it here: gemini_v116.tgz.