Observing Checklist for Imaging
with 24" Telescope Using CCDAuto (linux machine)

Unix commands are shown in italics.
Commands in the ucirob program are in red.
Commands in the CCDAuto program are in blue.
Commands in Xephem/SkyView are in green.

  1. The computer-controled AC power unit should be cycled on/off before starting up ucirob. That's the red lighted power switch beside the large connector on the front of the black box in the rack.
  2. If it is off, turn on the power strip that lies on top of the red tool bench. This powers the CCDs, and sometimes we turn it off if they are not used for a significant period of time just to prevent possible power surges.
  3. Log onto ucirob.ps as observer.
  4. Create your own directory for that night with mkdir, cd to it and make subdirectories named images, flats, darks.
  5. Start ucirob.ps from your directory.
  6. Open Obs. and when completed (see message screen) make sure the mirror covers are indeed all the way open. Sometimes the one facing South does not open all the way. If it is closed then use the ladder and gently open it.
  7. Power up the CCDs (CCDs button).
  8. Start CCCAuto program (FILE/Start CCDAuto ).
  9. Start up the ST9 - Imaging CCD (Cameras/Imaging CCD/Establish Link).
  10. Set the operating temperature to no less that 25 degrees C below ambient temperature (Cameras/Imaging CCD/Turn on Temp Reg and enter the temp in degrees C). Check that the power doesn't exceed 80% once the operating temp is reached. If it does you must raise the temp. If the dessicant in the camera has not been baked lately, the CCD window may frost over if the humidity is high and the operating temperature is low. You'll notice it as a large scale pattern on the CCD image, similar to fog on your bathroom mirror. If frost occurs, raise the temp (turn off temp reg) and take images until you find a temp that works. Remember the lower the operating temp is the lower the dark count and noise will be.
  11. Take a test image (Execute/Expose Singe Frame then Execute) to verify the ST9 is working.
  12. Start Xephem (FILE/Start Xephem).
  13. Open the SkyView window in Xephem (View/SkyView ).
  14. The scale button on LHS menu changes coords to RA/DEC in SkyView.
  15. Toggle Live Report (top button on RHS) to get cursor readout of RA/DEC.
  16. In Xephem 's SkyView bring up the Telescope/Configure panel, and it should read "lx200xed" and "queue". Click on Show Sky View Marker. Click on Running. Then click on OK in the status window that appears -- don't forget to do this because it completes the link between Xephem and ucirob.
  17. Plot the CCD Field-of-View in Xephem's SkyView by: (1) pulling down Control -> eyepieces - > ST9 (or whatever CCD it is), click Use then close the window, and (2) right click and select Place Eyepieces.
  18. In Xephem's SkyView, put cursor on an object and right click to get information on it.  Right click, and hold down right button to Center and Zoom on the object.  To slew the telescope to it, right click and hold the right button down and slide to Telescope GoTo.
  19. Move to a bright star near where you plan to observe, such as Vega, to varify the pointing of the telescope. Center the star in the field of view (CCD or eyepiece, but not the cente r of the CCD FOV is lower and to the left of the eyepiece FOV.). Check the small finder scope and make sure the star is centered in it, too. Reset home coordinates in ucirob, if needed (only do this if you are sure you know what you're doing!).
  20. Focus the telescope for the ST9 CCD. First, select the V-band filter in the CCD. Note that if you do not, it is likely in the "clear/open" position which does not have the same focus as when you are observing through a filter. Choose a bright star in Xephem that is located near the first object you plan to observe. Slew the telescope to it. Switch to the V-band filter and take a series of images of a bright star at different focus settings and measure the FWHM and Peak Flux for each to find the best focus, i.e. the focus setting that gives the smallest FWHM, highest Peak Flux, and the smallest scatter around a Gaussion-shaped radial profile. Find a star bright enough to record > 1000 ADU at peak in a 3 to 15 sec exposure. Note that you can change filters to increase/decrease fluxes (all the filters are parfocal). The minimum time of 3 sec will allow you to sufficiently average over temporal variations in the seeing caused by the atmospheric fluctuations. Use a focus step size of  ~15 units, and plan to try 5 to 7 focus values.  Step through focus values monotonically (either always decreasing or increasing) because there is some backlash in the motors when you change directions, and hence you want to avoid it. Under Telescope/Change Focus, enter a new focus value for the T Axis and click Move. Leave the TUV axes linked so that all three motors attached to the secondary will move by the same amount. (You would only unlinks them to change the collimation of the secondary mirror, but this should only be done by one of the professors!) Take an image with the ST9 with Expose. Click on Show Plot then click on the star. Record the FWHM and Peak Flux and note the size of the scatter around the radial profile fit. Repeat for the series of focus values and determine the best focus. Move the focus to ~150 units above/below the best focus and then back down/up to the best focus (to mitigate errors due to backlash). You may have to refocus periodically if the temperature changes greatly or as you move to different locations in the sky. Best focus is T = -5560, U = -5785, V = -5620 for the ST9 CCD for a temperature inside the dome of T = 22 deg C when recollimation was last done in June, 2005.
  21. If you want to use the finder/guider telescope (optional), initialize the guider CCD. Under Finder, click on the Settings button. Click on Link. It will initially fail claiming it can't set the video head offset. Click on Link again and it will initialize properly. Set the operating temperature  to no less than 20 degrees C less than the ambient temp and click on Temp Reg. Enter the desired exposure time (seconds), binning (1x1)  and hit Apply. Click on Expose to take an image.
  22. Mark the ST9 FOV on the guider image by clicking on ST9 Frame button.  To move the telescope so that a certain object in the guider image is moved  to the center of the ST9 FOV, right click on the object and tell the telescope  to move. To reset the default center of the ST9 FOV, click on an object in  the guider image which lies at the center of the ST9 image, left click on  the object, which enters the Star PSF values of  xc, yc, hwhm (although  hwhm is incorrect) then click on ST9 Center.  Turn the ST9 Frame off and on to redraw the frame at the new center. Note that the current default ST9 center is (x,y) = (156, 77).
  23. Field Sizes and Orientations:
  24. To begin guiding on a star in the guider FOV, first take an image to  make sure there is one in the field and define the needed exposure time. The star should have a maximum flux in the center pixel of a few thousand ADU. In the ucirob window, enter Guiding/AutoGuiding Settings to open the Autoguiding Parameters window. Set the exposure time and the interval between downloading an image and taking the next image.  Use a minimum of 10 sec as the interval. Hit Apply then click On to take the first image. The main ucirob window will tell you to left click on the star you want to use and then hit Select in the Current Guide Image window. Then it will take repeated images of a small subregion of the CCD surrounding that star. It will automatically send small slew movements to the telescope to keep you centered on that star. Unclick On in the Autoguiding Parameters window to stop guiding.
  25. When taking images with the ST9, to take another with the same exposure  time just click on Take Exposure in the Current Image window. To change exposure time or force a new dark image to be taken, you must pop up the Single Exposure Settings window (Exectue/Exposure Single Frame).  Remember to click on Apply after you change exposure time, etc. before hitting Execute.
  26. Remember to turn off the guider before slewing to a new object.
Shutting Down the Observatory
  1. CCDAuto/Cameras/Imaging CCD/Turn off temp reg, Close Link then File/Exit.
  2. In ucirob, under Finder/Settings turn off temp reg, and under Power Up turn off the CCDs button.
  3. In Xephem 's SkyView bring up the Telescope/Configure panel and unclick on Running. Then click on OK in the status window that appears. Then Exit Xephem.
  4. Close Obs under ucirob.
  5. Exit ucirob.
  6. Log off the computer and turn off the monitor, but DO NOT turn off the computer. We leave it on so that anyone can log in remotely from any unix machine and operate the telescope.
  7. If something goes wrong, call Profs. Smecker-Hane. Do not leave the telescope/ucirob if you are not sure the shutter is closed for the night!

Important Contacts:

If you run into a problem, you can call Profs. Tammy Smecker-Hane (824-7773 @ work, 509-7195 @ home).

If you need to reboot ucirob:

If ucirob crashes you may need to reboot the machine. You can't simply reboot the computer because the computer will be sending random signals to the rack. If you do, you're likely to get random motion of both the shutter, dome and lights! Instead follow this sequence:

  1. Turn off the power to the rack (red button on top of rack) and turn off the power to the AC controllable outlet box (red button on the middle box in the rack) .
  2. Reboot the computer.
  3. Enter ucirob, which will set the state of the electronic input to the crate. Then exit ucirob.
  4. Turn the rack and AC controllable outlet box back on.
  5. Restart ucirob. Send the dome to the home position (Observatory/Send Dome Home) to make sure its properly initialized.

T. Smecker-Hane
UCI Observatory
Last updated on 12/02/09
Department of Physics & Astronomy