C40/CCD Observing Procedures

IMPORTANT: START BY CHECKING THAT WE HAVE THE RIGHT FILTERS IN THE CAMERA: LC-3012 (U), LC-3013 (B), LC-3014 (V), LC-3015(R), LC-3005(T2).

Initializing systems

• 1. Update UT in DATA PC (located in light blue rack)
  • Username: root
  • Password: check label on monitor
  • Type 'date -z0'
  • Type 'date -d0'
  • Type 'date yyyymmddhhmm.ss'
  • Type 'date' (to confirm entry)
  • Type 'exit'
  
  
• 2. Start CCD Control Window in Data Acquisition Computer (Henrietta)
  • login: obs40
  • password: check label on monitor
  • cd /export/data1/obs40/ccd_data/mario/
  • mkdir 20020914_15 (e.g.)
  • cd 20020914_15
  • cp ../filter.names . (or edit file with 6 filter names)
  • ccd (opens CCD control window)
  • before the CCD control window appears you have to select 4 parameters from the menu:
    • Curtain
    • Site3
    • 32
    • LCO-40
  • On the CCD control window select Gain 3
  • On the CCD control window select Subraster and enter the following values
    • 824 2024
    • 1378 2578
    • Click Apply
    • Click Done
  • Open an IRAF window and change to the recently created directory (20020914_15)
  • Set uparm=/export/data1/obs40/ccd_data/mario/uparm/
  • Open XImtool
  
  
• 3. Activate Telescope
  • Turn console ON (rotate key)
  • Turn Power ON
  • Set Focus to 27.0
  • Check that platform is clear and in TCC-Guider PC, type 'COVER' (telescope will slew south)
  • Go to the platform, raise platform, and remove the telescope cover
  • Lower platform
  
  
• 4. Initiate Guider
  • Bring telescope to the zenith
  • From any window in Henrietta computer type command 'rgdr', which will open guider window
  • A new window will appear where you need to enter -96 in X box and 2076 in Y box (next to GOTO box)
  • Click GOTO and SETCENTER
  • Click PARK before taking calibrations

Calibrations

• Turn OFF platform lights from console
• Set focus value to 27.20 (upward) before taking flats
• In TCC-Guider PC, type 'DOMEFLAT' to slew telescope to white screen
• Turn ON quartz light from grey box over lightblue rack and adjust voltage to 900 units
• Check that lamps are pointing to the white screen and make sure that the illumination of the screen is truly uniform
• In 'ccd' window set exposure time, filter, Loop to 7, Imtype to flat, and object to "Dome Flat"
• Exposure times:
  • B: 120 sec (10000 cts/pixel)
  • V: 20 sec (8000 cts/pixel)
  • R: 10 sec (15000 cts/pixel)
  • I: 5 sec (12000 cts/pixel)
• Start sequence with START botton
• When the sequence of flats is complete turn OFF quartz lamp on grey box
• In 'ccd' window set exposure time to 0, Loop to 10, Imtype to zero, and object to "Bias"
• Start sequence with START botton
• Turn OFF quartz light from grey box over lightblue rack

Opening dome, and Preparing Telescope Control System (TCS)

Before sunset you must do the following:


• Turn ON fans in adjacent room (turn ON switch and set reostat near maximum value)
• Push OBTURADOR on console to open shutter
• Push PANTALLA on console to lower windscreen
• Push ASENCION RECTA on console to turn ON tracking
• In TCC-Guider PC, type 'DOME AUTO' to activate dome rotation
• In TCC-Guider PC, type 'TP' to activate telescope pointing model (this is not necessary if the model is already activated; check the TCS screen)
• In TCC-Guider PC, type 'MP 2002.5' to set the coordinate epoch
• In TCC-Guider PC, type 'roff -25.65' and 'doff -229.05'
• Turn on power of guiding camera in lightblue rack, and turn OFF 'bright' button

Skyflats

At sunset you must begin taking sky flats:


• SLEW telescope to the East
• In TCC-Guider PC, type DBB 20 (set step to 20 arcsec)
• In 'ccd' window set exptime to 3 (minimum), choose U filter, set Imtype to flat, and object to "Sky Flat"
• Start exposure with START botton
• After completing the exposure in TCC-Guider PC, type SS to slew telescope south by 20 arcsec
• Take 5 frames per filter with exposures longer than 5 sec and never exceeding 28000 adu.

Telescope Zero-Point

• In TCC-Guider PC, type RA hh mm ss.ss, and DEC dd mm ss (ccordinates of a bright star near the zenith)
• In TCC-Guider PC, use the SLEW command to slew the telescope to the desired position
• In 'gdr' window click CENTERFIELD; You should see the bright star in the guider field of view
• Use the paddle to bring the star to the red cross and focus guider camera
• In TCC-Guider PC, type CSET to zero-point the telescope

Focusing the Telescope

• Point to a 10th magnitude star
• Click PARK in 'gdr' window
• In 'ccd' window click OFF next to subraster (the full CCD will be read), set exptime to 10, Loop to 7, filter=V
• Use focus bottons to set focus reading to 0 in box located above console (always moving upward)
• In 'ccd' window click FOCUS to start first exposure of 10 seconds
• Once the first exposure is complete increase focus by 50 units and click on FOCUS again.
• Complete sequence of 7 exposures
• In IRAF window display image 'focus'
• On console set the focus to the best value
• Don't forget to enable the subraster in the 'ccd' window (click ON)

Using the guider

• Use TCC to SLEW telescope to your target
• In 'gdr' window click CENTERFIELD. You should see the target.
• Use the paddle to move the target to the red cross (the object should be at the center of the CCD frame)
• In 'gdr' window click PARK to remove guider from the field of view of the CCD
• In 'gdr' window turn ON the KEYPAD and use arrows to move the guider around until you find a guiding star
• In "GUIDER" enter the parameters of the camera (check sheet)
• On the TCS keyboard you can use the arrows to move the white box and put it on the guiding star
• On the TCS use F3 to activate guider
• On the TCS use F1 to de-activate guider

Observing

• In 'ccd' window set Imtype to object, select exptime, and filter
• Check exposure times here.
• Don't forget to apply focus offset for the selected filter
  • U: +0.04
  • B: +0.14
  • V: 0.00
  • R: +0.13
  • I: 0.00
  • T2: -0.35
• Turn ON guider (F3)
• In 'ccd' window use START to begin exposure
• Turn OFF guider (F1)

Closing the Telescope

• Turn OFF power of guiding camera in lightblue rack
• Push OBTURADOR on console to close shutter
• Push PANTALLA on console to raise windscreen
• Push ASENCION RECTA on console to turn OFF tracking
• In TCC-Guider PC, type 'DOME IDLE' to de-activate dome rotation
• In TCC-Guider PC, type 'DOME PARK' to park dome to the south
• In TCC-Guider PC, type 'COVER' (telescope will slew south)
• Go to the platform, raise platform, and put on the telescope cover
• Lower platform
• Turn OFF fans in adjacent room (turn OFF switch and set reostat to zero)
• In TCC-Guider PC, type 'ZENITH' (telescope will slew to the zenith)
• Turn Power OFF on console
• Turn console OFF (rotate key)
• Turn OFF monitors in control room
• In 'gdr' window click CENTERFIELD
• Fill out Night Report here
• You can go party now
  
  mhamuy@lco.cl