C100/CCD Observing Procedures
Last modified: Feb. 27 2014, 11:55 PM (Nidia)
1. Accessing Data Acquisition Computer (Clarity)
- Username: obs1, obs2 or obs3 (check with staff)
- Password: check with the staff
- Open an xterm window
- Most probably the current and following steps will be performed by
the technical staff and the instrument GUI will be already running when you
start, thus better check before.
2. Start Detector Control Window
Clicking the OK button will start the CCD GUI from which the exposures
- In xterm type 'ccd'
- A dialog window will open
- Observer: SN
- CCD: SITe2K-1
- Overscan = 128 (default)
- Instrument: Direct
3. Dome Flats
When the sequence of flats is complete turn OFF quartz lamp
Set ExpType=Bias (this will automatically set ExpTime=0), Loops=10,
Object: bias, and take a sequence of bias frames.
- Check that the platform lights are OFF
- Turn ON quartz light and adjust voltage
- Set speed: Fast (and keep it during all the observations)
- Set Object: dflat
- Set ExpTime, ExpType=Flat, Loops=10 (15 may be better, if time
allows), and take a sequence of flat frames
- Exposure times for CSP filters:
- B: 20 sec (~19000 cts/pixel) (voltage=480)
- V: 20 sec (~23000 cts/pixel) (voltage=400)
- g': 20 sec (~20000 cts/pixel) (voltage=400)
- r': 15 sec (~20000 cts/pixel) (voltage=340)
- i': 15 sec (~19000 cts/pixel) (voltage=305)
- u': Take SKY FLATS at sunset (set Object: sflat, do not expose
shorter than 5s, get at least 5 sky flats).
4. Telescope Pointing
5. Telescope Focus
- Ask your NA to point the telescope to a bright star
- Take a short image
- Compute telescope offset to place star near x=1300 y=1024, avoiding the
bad column around x = 748. In the Quick-Look tool display North is
left and East is up. The image scale is 0.259 arcsecs per pixel.
- Take another short exposure to confirm pointing.
- Ask the NA to CSET the telescope
- Ask the NA to move the telescope a bit away from the bright star used
- In CCD GUI set ExpType=Focus (this will automatically set Loops=7),
set filter=V, ExpTime=10, and press 'Start' to begin the focus sequence.
A dialog window
will pop up after each 10s exposure waiting for the focus to be adjusted; hit
'continue' to resume sequence. The focus image will be saved to a
current image name; i.e. ccd????.fits
- Imexamine the image (as of Nov. 25th, 2010 best focus is ~4900)
7. End of night
- Set ExpType=Object
- Focus offsets (as of Nov. 25th, 2010; anyway it's a good idea to check
with a short exposure on the target before starting a sequence):
- B: +10
- V: 0
- u': -39
- g': -43
- r': -43
- i': -44
- Data should be copied over to csp2 /raw e.g.
scp -r ../20140225_26/ observer@csp2:/raw/DUP_DC_20140225_26
where observer is user name of the observer in csp2.
- To launch the reduction pipeline log into your accound on
csp2 and type the following command line:
- Wait for until the system issues a message such as:
which means the reductions have started.
Then you can log out from csp2.
- Note that for the pipeline to work it is necessary that you follow the
CSP naming conventions for the 'Object' field in CCD GUI:
- SN_name (as in CSP Swope Queue), for example CSP14aap, SN2013gr, etc.
- If an exposure has to be ignored by the reduction software (for example,
a short exposure taken to check focus you forgot to override) add the
suffix 'bad' to the object name, for example: CSP14aap_bad.
To do that, in the IRAF window, type:
cl> imrename ccd????.fits CSP14aap_bad