This web page provides information regarding the acquisition and implementation of the DEEP2 DEIMOS data reduction software.


New optical model for the 600ZD grating (2017-Apr-07)
Some observers have recently experienced issues with the wavelength calibration of multi-slit data. This is very likely caused by the default optical model parameters in the pipeline not being representative of the system after March 2016 sevice mission. Peter Capak has kindly provided a new optical model parameter file ( for the 600ZD grating at 7200A in slider 3 and 4. To run the pipeline with the new optical model parameters, simply replace the file deep2/cvs/spec2d/pro/ by the new file in the link above.
We are working to provide a new optical model parameter file for all gratings in both sliders


The DEIMOS data reduction pipeline was developed by the DEEP2 survey team at the University of California, Berkeley (UCB). The pipeline is based upon the Sloan Digital Sky Survey (SDSS) spectral reduction package as written by David Schlegel, Scott Burles, and Doug Finkbeiner. Nearly all of the pipeline code is written in IDL and is maintained under CVS. The DEEP2 CVS repository contains all of the DEIMOS specific code (spec2d package), but the core IDL utilities (idlutils package) are maintained by the SDSS team at Princeton. You will need both packages to use the DEIMOS data reduction pipeline; please consult these instructions on downloading both sets of software.

Running the Pipeline at Keck

Observers typically install and run the pipeline on their own computer, but are welcome to run the version we have installed at Keck. To do so, simply log into any DEIMOS numbered observing account on the data reduction machine hamoa, and execute the command deep2drp to launch and IDL session configured to run the pipeline. Alternatively, from a DEIMOS numbered VNC session, select
	DEIMOS Utilities > DEEP2 DRP

Using the Software

The DEIMOS pipeline software, contained in the spec2d package, was specifically designed for the purpose of reducing DEEP2 survey data. Considerable efforts were made by the DEEP2 team to generalize the pipeline for general mask designs and instrument setups. The success of the pipeline will undoubtedly vary depending on the choice of grating, the wavelength range of the data, and the slitmask design specifications. At present, the pipeline is best suited for handling data taken with the 1200 l/mm grating at red wavelengths (lambdac ~ 7700Å).

It is important to note that the DEEP2 DEIMOS code is not fully generalized; the pipeline has certain limitations such as the inability to account for dithering. Please see our brief notes for more on this and other issues regarding slitmask design. The spec2d reduction package takes the raw DEIMOS data as input and produces a variety of outputs including sky-subtracted, 2-d slit spectra and extracted 1-d object spectra. For more details on the spec2d code and its data products, please read the spec2d primer. For assistance in running the pipeline, refer to the spec2d cookbook. Please direct questions and comments regarding this web page to .

Staying Informed

To facilitate the dissemination of information regarding the status of the spec2d pipeline (release of new versions of the code, etc.), a spec2d users email list has been organized. If you wish to be added to this email list, please send an email request to with the following Subject line:
      subscribe to spec2d_users list
Otherwise, major announcements including version release details will be posted at this website. Also, refer to our FAQ page for possible answers to any questions that you might have.

Providing Acknowledgment

For any publication utilizing data analyzed via the DEEP2 DEIMOS spec2d pipeline, please include citations to both of the following references:

See Also