C100/WFCCD Observing Procedures

1. Accessing Data Acquisition Computer (Canopus)

2. Start Detector Control Window

In current directory edit file 'filter.names'
- B
- V
- Grism Blue
- I
In current directory edit file 'aperture.names'
- Pinhole
- Slit 1.65 (150u)
- Slit 8.35 (750u)
- Open
In current directory type 'ccd' to open detector control window
Before the CCD control window appears you have to select 4 parameters from the menu:
- WF CCD
- TEK5
- 16
- LCO-100
On the CCD control window select Gain 1
On the CCD control window select Subraster and enter the following values:
- 1 1790 500 1500
- Apply
- Done
Open xgterm window
cd /export/home/obs100/iraf
Type cl to start IRAF
reset uparm=/export/data1/obs100/ccd_data/mario/uparm/
Load the 'wfccd' package
Go to the recently created directory (20020914_15)
Open XImtool

3. Check Masks and Arc lamps

Take short (2-sec) exposures of both masks using dome lights
Make sure image is not saturated and measure slit coordinates with imexam --> (xs,ys) (should be ~1408,470)
Turn ON He and Ne arc lamps and take short (10-sec) exposure
Check that wavelength range is correct and that lines are in focus (2-3 pixels wide)
Check that spectral lines are duly aligned with CCD columns (within 1-2 pixels)

4. Dome Flats

Turn OFF platform lights
Turn ON quartz light and adjust voltage to vales given below
In CCD window set Filter, Aperture=Open, Loop=7, exposure time, Imtype=flat, and object="Dome Flat"
Exposure times:
- B: 15 sec (voltage=350)
- V: 15 sec (voltage=300)
- I: 5 sec (voltage=250)
- 1.65" slit: 10 sec (voltage=480)
- 8.25" slit: 5 sec (voltage=480)
Start sequence with START botton
When the sequence of flats is complete turn OFF quartz lamp
Set exptime=0, Imtype=zero, Loop=10, and take a sequence of bias frames

5. Telescope Pointing

Point to a bright star
Take direct image while rotating the instrument and determine center of rotation (xr,yr)
Take direct image
Compute telescope offset to place star at center of rotation which is probably near (904,509)
Ask the NA to update the ZP of the telescope

6. Telescope Focus

Set Subraster to OFF
Point to a bright star
In CCD window set Loop=7, set filter=V, Exptime=10, and use FOCUS (not START) command
Imexamine the image (best focus is ~4580)
Turn ON Subraster

7. Observing

Changing the gain during the night is not recommended since it's easy to forget to reset it.
Set Imtype=object
Ask NA to point the telescope to object
Use 'pangle' to determine paralactic angle and ask the NA to set the rotator angle
Edit parameters for 'toslit', enter rotator angle, coordinates of rotation center (xcen,ycen), (xs,ys)
Run 'toslit' and ask the NA to offset the telescope (a big offset which should bring the object close to the slit)
In CCD window set Aperture=Open, Filter=V, and take direct image of the field
Edit parameters for 'cobject', set mark=yes, coordinates of guider box, and the object's CCD frame
Run 'cobject', mark object (space bar), use the CAMERA offset yielded by 'cobject', and ask the NA to move the guider box accordingly
In CCD window set Filter=I, and take direct image of the field
In CCD window set Aperture="slit 1.65" and take 5-sec exposure of narrow slit mask and measure (xs,ys)
Edit parameters for 'cobject', and enter (xs,ys)
Run 'cobject', mark object (space bar), use the CAMERA offset yielded by 'cobject', and ask the NA to move the guider box accordingly
In CCD window set Filter="Grism Blue", Aperture="slit 1.65", exposure time, object to "object name", and click START to begin exposure
Turn ON He and Ne lamps, ask the NA to close dome shutter, and take 15-sec exposure (don't forget to remind the NA to disable guider)
Turn OFF He and Ne lamps, and ask the NA to open dome shutter

7. Before going to bed