C100/RetroCam Observing Procedures

Last update for this manual to be used on the C100 telescope on August 29th, 2012 (Nidia)


1. Initialize System

1.1 Instrument Control Computer: ARACHNE/CSP5 (Windows XP)

Back to top

2. Calibrations and Telescope Setup

Back to top

3. Observing

Back to top

4. Quick-Processing IRAF Scripts

  • A series of IRAF scripts are available in csp4 to help the observations.
  • The scripts are loaded automatically when you start IRAF. The task definitions are given in the 'loginuser.cl' file in ~/iraf/.
  • The script files themselves sit in ~/iraf/retro_quick/.
  • The following tasks are available:
    • dis:
      Displays an image without having to type in the whole name.
      Usage:    cl>  dis  num   loo
      where 'num' is the frame number, and loo is the loop number.
    • disi:
      The same as above but it starts imexamine.
      Usage:    cl>  disi  num   loo
    • dp:
      Displays the difference between two "_001" frames.
      Usage:    cl>  dp  num1   num2
      where 'num1' and 'num2' are the frame numbers of the images to be subtracted.
    • pdiffi:
      Displays the difference between any loop of two frames and starts imexamine.
      Usage:    cl>  pdiffi  num1  num2
      by default, it subtracts loops "_001" of both frames.
      You can edit the optional parameters 'l1' and 'l2' to use other loops.
    • avgo:
      Displays the difference of two frames after averaging all the loops in each one.
      Usage:    cl>  avgo  num1  num2
      You can modify the optional parameter 'scl' to change the scaling factor to be applied before subtraction --- scl = "mode" is the default.
    • sky_stats:
      Shows the median and mean sky level for a range of frames. Useful to check flats.
      Usage:    cl>  sky_stats  num1  num2
      where 'num1' and 'num2' give the range of frames to analyze.
    • p_fid:
      Mark a fiducial star used to align dithered images.
      Usage:    cl>  p_fid  r  num1  num2  aut/man
      where 'num1' and 'num2' give the range of frames in a sequence. Options 'aut' or 'man' allow to make the program select a star, or the user to mark it. The task will write the star position in the headers of frame num1.
    • p_fx_asecs:
      Correct the RA and DEC offsets between frames that are written in the header keywords ASECS and DSECS.
      Usage:    cl>  p_fx_asecs  r  num1  num2
      where 'num1' and 'num2' give the range of frames in a dither sequence. The user will be prompted to mark the same star in all frames (after averaging the loops). r_quick will usually fail if this is not done in advance.
    • p_mimdel:
      Delete a range of frames of some kind.
      Usage:    cl>  p_mimdel  pre  num1  num2
      where 'pre' is a frame prefix ('icr' for loop-combined, 'isx' for sky-subtracted, etc.), and 'num1' and 'num2' give the range of frames in a dither sequence. Since p_fx_asecs fixes the headers of 'irr' frames only, you will need to delete the 'icr' frames before running r_quick, in order to get the right offsets.
    • r_quick:
      Produce a quick and dirty stack of a range of frames.
      Usage:    cl>  r_quick  num1  num2
      It produces a sky by averaging the frames. It asks the user to mark a few stars with 'a' in imexamine. It may fail if the dither steps are too large (>30''), or if the guider star got lost.
    • rcmosaic:
      This script allows to run all the necessary steps to produce a quick staked image at once.
  • To make a fast combination of a dither sequence:
    For example, a sequence of frames 10 to 18.
    • p_fid r 10 18 aut
    • p_fx_asecs r 10 18
    • p_mimdel icr 10 18
    • r_quick 10 18
    • Alternatively, just type: rcmosaic 10 18 and follow the instructions that will be displayed.
Back to top

5. Copying Data to a CSP Machine

    At the end of the night, you must transfer data from Rigel to the /raw directory in csp2.
    From a terminal in Rigel, cd to /Volumes/Data_Rigel and then type:
    scp -r name__of_the_night user@csp2:/raw/DUP_RC_name_of_the_night where 'name_of_the_night' is, for exapmle, 20120828_29 and 'user' is your login name on csp2 computer.
    Back to top href="#rep">below)
Back to top

6. Before You Go to Bed

    6.1 Fill in CSP Night Report and SN Logs

    • Fill in the CSP Night Report. (User name and password required.
    • In the "Night time report" field, inform about objects observed and calibrations taken. Give details about weather conditions and describe technical problems, if any.
    • Fill in the CSP SN Log of the night. (User name and password required.)
    • This form allows you to input all the SNe of the night at once in a comma-separated list.
    • In the Filters field you can input a generic 'YJH'.
    • Click on Submit and an editable list will appear.
    • Modify the fields according to what you observed in the night.
    • In particular, check the Filters and Weather fields because these may change from SN to SN.
    • The rest of the fields will generally have the same information for all the SNe.
    • Click on Submit to send the logs to the database.
    Back to top

    7. Linearity Tests (Only for Cloudy Nights)

    • Wait until it is dark outside and close the dome.
    • Turn OFF the incandescent dome lights from the console.
    • In TCC-Guider PC, type 'DOMEFLAT' to point the telescope to the white screen.
    • In RetroCam-Control window set:
      • Filter = Yc
      • Readmode = Double
      • ObjType = dflat
      • Loops = 1
      • Object = Linearity
    • Turn ON the quartz light from the grey box over light blue rack and adjust voltage so that you get 2000 ADU in 10 s (550 V should be OK).
    • Take the following series of exposures, changing ExpTime each time to the values below, and pressing Go.
      ExpTime values: 10, 3, 10, 7, 10, 15, 10, 20, 10, 30, 10, 45, 10, 60, 10, 75, 10, 90, 10, 105, 10, 120, 10, 135, 10, 150, 10, 165, 10, 180, 10, 195, 10, 210, 10, 225, 10, 240, 10, 255, 10.
    • You must reach about 48,000 ADU in 255 s.
    • Turn the quartz light OFF and take Darks at each Exptime above, using Loops = 1.
      In RetroCam-Control window set:
      • Filter = dk
      • Readmode = Quadruple
      • ObjType = dark
      • Loops = 1
      • Object = Dark
    • Only ONE dark at 10s is needed.