McDONALD OBSERVATORY

INTRODUCTION TO MT.LOCKE COMPUTING

INTRODUCTION

This manual is designed for the new McDonald observer or for those who just need help. For additional information see the Observing Support page or the Online Manuals.

TABLE OF CONTENTS:

• Systems:    List of all the computer systems at Mt.Locke, their type, location, and tape drive names.
• Data Collection:   List of instruments, the program name used, system it runs on, and the invoking cmd.
• Data Archival:   Help for archiving your data to take home with you.
• Telescope Pointing:   How to use the computer systems to get coordinates for your objects.
• Computer Access:   How to access the computers at Mt.Locke.

SYSTEMS

McDonald Observatory supports the following types of systems...

If you need an account, please contact John Kuehne (jwkuehne@astro.as.utexas.edu) or Darrin Crook (crook@astro.as.utexas.edu).

DATA COLLECTION

See the various individual manuals for the actual operation of each program.

DATA ARCHIVAL

*** NOTE: USERS MUST SUPPLY ALL ARCHIVAL MEDIA. ***

CCD Data

Most Sun Sparc Stations have 8mm Exabyte tape drives.

• All drives but one (in the 2.7m control room) are capable of writing in the 8200 format (2.3Gbyte/tape).
• The drives at the 2.7M and 0.8M are capable of additionally writing in the 8505 format (10 Gbyte/tape). HOWEVER, it is recommended to use only the 8200 format unless you are sure that you have a drive capable of reading the higher density formats (there are very few of them in Austin). One of the drives at the 2.7m telescope will ONLY write in high density, though it can read a low density tape if the tape is write-locked. All Suns are capable of writing your data in the FITS format, HOWEVER we suggest using TAR unless there is a specific reason that you need FITS. The TAR tapes will write in about 1/10 the amount of time it takes to write a FITS tape, with fewer problems.
• If you are using one of the "true blue" Sun 8mm drives and the top and bottom LED start to flash, don't panic! This means that the tape drive's internal counter says it needs to be cleaned. Eject your tape after you are finished with the current operation and place a cleaning cartrige in it. When it is finished cleaning itself, it will eject the cleaning tape and the LEDs will turn off. Please make sure to log the cleaning on the cleaning tape and/or on its box (cross off one of the boxes). If all of the boxes are full on log, toss the cleaning tape in the trash, note it on the night report and another cleaning tape will be provided.
• There is currently only one 4mm DAT drive availble at Mt.Locke. It is located at the 2.7M and connected to Oberon (2.7M Data Collection Sun) and can be accessed either via IRAF (mtao) or TAR (/dev/rst0/dev/nrst0). (See all the tape drive designations above.)
• NOTE: Some data disks are NFS mounted on all systems so you may not need to copy your data over to another machine to use its tape drive. If you would like to write your data from a non-mounted system, please call computer support for help.
• Writing data to tape. Please note that these are merely a couple of suggestions for ways to write your data. There are other procedures for both tar and IRAF writing of your data.
  
  
  • In IRAF, go to your data directory, place your tape in the drive, then type 'dataio' to enter the tape-writing package. Then 'epar wfits'. Edit the file as shown in the sample below. The FITS filename (line 2) must correspond to the particular tape drive you are using. Line 3 should be 'yes' or 'no' depending on whether your tape is blank or not. See above for all the IRAF tape drive designations.

    
                                       I R A F  
                        Image Reduction and Analysis Facility
    PACKAGE = dataio
       TASK = wfits
    
    iraf_fil=                *.fits  IRAF images
    fits_fil=                  mtt  FITS filename(s)
    newtape =                  yes  Blank tape?
    (fextn  =                 fits) Extension to append to output disk FITS filename
    (extensi=                   no) Write all images to a single FITS file ?
    (global_=                  yes) Prepend a global header to the FITS extensions f
    (make_im=                  yes) Create a FITS image file?
    (long_he=                   no) Print FITS header cards?
    (short_h=                  yes) Print short header?
    (bitpix =                    0) FITS bits per pixel
    (blockin=                    0) FITS tape blocking factor
    (scale  =                  yes) Scale data?
    (autosca=                  yes) Auto_scaling?
    bscale  =                   1.  FITS bscale
    bzero   =                   0.  FITS bzero
    (mode   =                   ql)
    

    Type 'CTRL-D' to exit the editor, then type 'wfits' to begin the transfer. When done, remove your tape from the drive and exit IRAF nicely (lo). Just exiting your windows at this point without exiting IRAF first may cause problems for the next observer.
  
  
  
  • Writing to a tar tape. This is easier, much, much faster and much less likely to hose up. From a UNIX shell, go to your data directory Place your tape in the drive.

          tar cvf /dev/nrst4 .          (does not rewind the tape when done)
          tar cvf /dev/rst4 .           (rewinds the tape when done)
    

    For other tape drives at the 2.7m, see the designations above. All of the tape drives on /dev/nrst4 can hold about 2.3GB of data.

  Photometry and Polarimetry

  All IBM-PCs have 3.5 inch high density floppy drives as well as a hard drive for real time storage. All QUILT data are written in ASCII format and can be copied from the hard drive to a floppy with a normal MSDOS copy command.

  ---

  QUICK LINKS: Intro | Systems | Data Collection | Back to the top | Data Archival | Telescope Pointing | Computer Access | Back to the top

  ---

  TELESCOPE POINTING

  Telescope pointing is currently handled by the data-taking Suns. Each dome has its own setup on the Sunfor pointing and data collection/reduction. The pointing for the 0.8m telescope is handled by Miranda, the Sun at the 2.1m telescope. The pointing is handled by a group of programs that are known as the SUNPOINT programs. The SUNPOINT programs take care of the zero offsets (except at the 30"), the calculation of the coordinates as well as feed back to the host data collection program of the current location of the telescope. See the McDonald User Manuals and the messages when you open a window on the Suns for each telescope for more information on SUNPOINT and pointing.

  Coordinate Files

  Coordinate files brought to the observatory should be in the format shown below. They should be in a file called worklist.dat and should be in the home directory of the user on the computer used to run Cosmo/Point. The list immediately following is a star list.

    
      1 "ETA CAS   " 00 46 03.7  57 33 03  1950.0   0.137 -0.52    6.50  2.685
      2 "TAU_CET   " 01 41 44.7 -16 12 01  1950.0  -0.119  0.86    5.57 50.000
      3 "THETA PER " 02 40 46.3  49 01 06  1950.0   0.035 -0.08    4.59  1.695
      4 "IOTA PER  " 03 05 26.7  49 25 27  1950.0   0.130 -0.08    4.18  1.549
      5 "ALPHA FOR " 03 09 56.8 -29 10 59  1950.0   0.025  0.64    4.10  8.497
      6 "KAP 1 CET " 03 16 44.1  03 11 17  1950.0   0.018  0.10    3.99  2.166
      7 "EPS ERI   " 03 30 34.4 -09 37 35  1950.0  -0.066  0.02    3.76  2.587
      8 "DELTA ERI " 03 40 51.0 -09 55 53  1950.0  -0.007  0.75    3.59  2.413
      9 "OMI 2 ERI " 04 12 58.2 -07 43 46  1950.0  -0.150 -3.42    3.05  1.896
     10 "PI 3 ORI  " 04 47 07.4  06 52 32  1950.0   0.031  0.02    2.48  1.348
  

  The coordinate field begins with a 5-character integer as shown above (lead with spaces). This is significant. The object name is a 10-character field. Do not begin an object name with a number. The coordinates themselves are in hours, minutes and seconds of RA, as shown above, followed by declination in degrees, minutes, seconds. A `+' is not necessary for positive declinations and you need not reserve a space for it. The epoch of the coordinates follows at the end. 2000.0 is the current default if none is given. This is followed by RA proper motion and DEC proper motion. Proper motion is not required by the Point program. The last 2 fields may be magnitude and color index. They are not required and are for your information only.

  ---

  QUICK LINKS:  Intro | Systems | Data Collection | Back to the top | Data Archival | Telescope Pointing | Computer Access | Back to the top

  ---

  COMPUTER ACCESS

  The 2.1m dome has a terminal which is connected to Prometheus in the control room to display pointing information.
  The 2 computers, a PC and a Mac, located in the AL dining room and the computer located in the 82" library are available for general use. From these, one can ssh (secureshell) to your home machine or wherever.
  In the control rooms of the telescopes and other various locations there are Ethernet ports for general use.
  There are wireless hotspots located in the 82" library and the AL dining room and lounge.

  ---

  QUICK LINKS:  Intro | Systems | Data Collection | Back to the top | Data Archival | Telescope Pointing | Computer Access | Back to the top

  ---