LRIS: Slitmask Submission Procedure

The Slitmask Database

The slitmask processing system maintains slitmask information in a database, currently residing in California. To submit slitmask files for milling, LRIS observers use the same web forms that DEIMOS observers user. To use the LRIS/DEIMOS slitmask submission web form, observers must register and may need to request access for their Internet domain.

Registering with the Slitmask Acceptance System

To verify that you can access the web pages, you should register with the system as soon as possible by following this procedure:
  • Use your web browser to open the DEIMOS/LRIS slitmask observer page at
    https://www3.keck.hawaii.edu/observers/Slitmask/rel/index.html
  • You'll need a Keck Observer Account. If you do not have one, you can create a new account from the login page.

Submitting a Mask Design File

You may submit an LRIS or DEIMOS Mask Design File as follows (the procedure is identical for the two instruments):
  • Use your web browser to open the DEIMOS/LRIS slitmask observer page at
    https://www3.keck.hawaii.edu/observers/Slitmask/rel/index.html
  • Click on the Submit a Mask Design File button to reach the Submit Mask Design File page.
  • Enter the filename to upload (you can use the Browse... button to get a file selector widget for easy navigation of your file system) and click the Send to upload your file. Your browser should now show the Upload Confirm web page.
  • Validation is done upon submission. If there are errors, correct the errors in the MDF file and submit again.

Verifying Your Slitmask

After submitting mask design files, you should check that they have been ingested into the system properly by listing your slitmask inventory: For each mask, the page provides a dropdown menu to do various things:
  • Archive. Archiving a mask sets the status of the mask so it no longer is in the Milling Queue or Available for use. The mask remains in the database, however, it must be set to ReMill (and be remilled) if the mask is to be used (again).
  • Remill. After being milled, masks are marked "done" so that they don't pop up again in the "to be milled" list. To make another copy of a mask that has been milled already, you will need to mark it "unmilled" using the Remill button.

    NOTE: it is a Bad Idea to use the "Remill" button to use a slitmask from a previous run, since the date of observation will be wrong and this will goof up the slitmask milling list. Instead, regenerate the mask design file with DSIMULATOR and submit the revised version.

  • Plot. The Plot button is not dangerous. It shows you a graphical representation of your mask design.
  • FITS file. The FITS file button is not dangerous. It generates a 'FITS chunk' for any mask design. Note that this takes a long time to generate and is probably not interesting to you.
  • Detail. The Detail button is not dangerous. It shows you in terrifying detail all the data contained in your mask design and blueprint(s).
  • You'll receive immediate feedback regarding any problems with the content of your slitmask files.
  • You'll be warned via email if alignment boxes are not present on your slitmasks.
  • You can quickly generate plots of your slitmasks to verify the layout of the slits.
  • If you accidentally give two of your masks the same nickname, an automatic data quality checker will rename the second and subsequent masks to guarantee uniqueness.
  • You can easily request that masks be dropped from the queue, or that old masks be entered into the mill queue again.
  • You'll be sent email updates on the status of your masks, indicating whether they've been milled or not, and you can check the status of your masks via the web pages at any time.


    Slitmask Policies

    • Slit Mask Files for those using multislit masks with LRIS or DEIMOS with less than 200 slits are required FOUR weeks prior to the observing run. Masks with greater than 200 slits are required EIGHT weeks prior to the observing run. Beginning with semester 2005B (1 August 2005) we will begin to charge for late submittal of mask designs unless sufficient scientific justification is provided. Please read the Policy on slitmask incentives for further information.
    • Masks submitted after the four week deadline will go to the end of the slitmask queue and be milled after the completion of all on-time masks, even if the on-time masks were submitted after the late masks.
    • We understand that certain time-critical observing programs (i.e., supernova searches) require that masks be designed and milled within a day or two of the run. CARA will continue to support such bona fide time-critical requests when possible. To request permission for late slitmask design files, please contact Dr. Bob Goodrich (rgoodrich) at the keck observatory and provide him with the scientific justification for the request.
  • Last modified: 09/20/2024 01:11
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