BUSCA Manual Version 0.9a Oliver Cordes (email:  ocordes@astro.uni-bonn.de ) Bonn/Calar Alto , May 2001

• Introduction
• Overview
• Technical data
• The BUSCA team
• How to observe
• Startup
• Data aquisition
• Closing
• CCD frame definitions
• Setting the observer data
• Error messages
• Instruction for technician
• Startup (for technicians)
• Closing (for technicians)
• Sounds (for technicians)
• The BUSCA gui
• Main menu
• TCP control
• BUSCA software  directory tree
• Configuration
• FAQ
• Glossar

1. execute the command start_busca in the instrument window or in a xterm;the BUSCA GUI appears on the screen
2. the initialization is finished when Program initialized! appears in the status line. (In case error dialog boxes pop up, click OK .)
3. if the status window CCD status is idle, choose CCD->Voltages on from the menu, the CCD should switch to continuous scan
4. check the temperatures and the LN2 status of all channels in the status window (should be green or OK)
5. enter the observer data (only necessary, if you start the software for the first time)
6. the system is now ready to observe
7. if you want to activate the sound output of the software you have to switch on the speakers above the monitors and to start the program audiocontrol in a xterm and press the button headphones

1. enter the exposure time and number of exposures you want
2. enter the object name or press the button last name on the right side  (the button is orange, if a last name is available)
3. choose the type of the exposure
• object
  for normal exposure(s)
• flat
  for flat field exposure(s)
• bias
  for bias exposure(s) (this mode is independed of the exposure time)
• dark
  for dark exposure(s)
4. choose the channels you want to read out or press the button all on the right side to select all channels
5. choose a CCD frame definition
6. press the button Start Exposure and the exposition begins, during an exposition you can press the buttons BREAK or Pause. BREAK means that you abort the current and following exposure(s). If you press Pause, you have the choose,to break or continue (e.g. when the dome vignets the pupil and you had moved the slit) the exposition
7. the exposition is finished, when you see Taking exposure(s) finished! in the statusline. If you have pressed BREAK (see above) you will see Taking exposures(s) aborted! You will also hear a double beep and a funny sound if you  have activated the sound output. (see  startup procedure )
8. in any case you can now start a new exposition!

CCD frame definition means in this case that you have to choose which part of the CCD you wanr to read out and which readout mode (binning) you want to use. BUSCA has four 4kx4k CCD devices. The pixel scale are 0.17" per pixel (15mu). To use the 4kx4k frame or a part of these frame means that you readout the CCD without any binning or with binning 1. For normal use at Calar Alto (seeing conditions up to 1") you can use the CCD in binning 2 mode. Then you have a pixel size of 0.34". You also reduce the readout time for the 2kx2k to 2:20s. The readout time for 4kx4k is about 8min.

There two different ways to choose a CCD frame definition:

1. use a predefined definition
   you have to choose one entry in the menubox in the middle of the exposure area labeld CCD-Frame.
• full frame bin2
  whole CCD frame 2kx2k (binning 2) (FOV  12'x12')
• central 1k+OS bin2
  the central 1024 pixel region of the CCD which is enlarged to the right to use the overscan ; region of the CCD (FOV  9'x6')
• central 512+OS bin2
  the central 512 pixel region of the CCD which is enlarged to the right to use the overscan region of the CCD; this mode is usefull and saves readout time if you want to observere Stroemgren standard stars, because normally there is only one bright star in the CCD field (FOV  3'x3')
• full frame bin4
  whole CCD frame 1kx1k (binning 4); this frame is usefull to create finding charts to check the telescope position
• full frame 4k
  whole CCD frame 4kx4k (binning 1)
• flat test bin2 (100^2)
  central 100 pixel region of the CCD (binning 2); usefull to check the exposure time and count rates during the flat field process
• flat test 4k (100^2)
  central 100 pixel region of the CCD (binning 1); usefull to check the exposure time and count rates during the flat field process
• central 1k bin2
  the central 1024 pixel region of the CCD (FOV 6'x6')
• central 512 bin2
  the central 512 pixel region of the CCD (FOV 3'x3')
• central 256 bin2
  the central 256 pixel region of the CCD ( FOV  90"x90")
2. make a user specific definition

To enter the observer data choose Config->Set observer data from the menu. In the dialogbox  you can enter these parameters:

• name of the observer(s)
• image directory (pressing the button beneath the entry line, you get an file selection box, one click with the mouse select a directoy, a double click enters a subdirectory); you can also enter a new directoy in the entry line, in this case you have to press OK and the program will ask you if it should create this directory, the first number will be then 00001
• prefix of the images (only two characters)
• the number of the first new image (-1 means, that the program calculates the next number by looking for the last image in the image directory with the selected prefix, on the right side the next number is displayed) NOTE: the default is -1!

startup error messages:
 

• Exhaust measure point at  dewar XX is broken or frozen!

This means that the program can't measure the  LN2  exhaustion. This happens normally after the filling of the dewars. The dialog correspends to the entry fail in the status window for the channel XX in line CCD-LN2. Click OK to continue!
• wheel XX: wheel not in a definite position. Reset forced!
  The  UC  was reset before, so the filter wheel has to be reset too. Click OK to continue!
• path XXX doesn't exist ! Create this directory?
  You has started the program the first time in this run and the old image directory, which was used by former observers doesn't exist. So if you like the directoy name, press YES and the directory will be created.  If you otherwise press  NO, you got the message that the savepath is set to /tmp. In any case you should setup the observer data  and set the name of the observer(s) and the prefix correctly.

1. execute the command start_busca  in the instrument window or in a xterm
2. after the main window appeared on the screen, there are sometimes some error dialog boxes, click OK in this cases
3. the initialization is finished, when Program initialized! appears in the status line
4. check the status window at the right bottom of the main window for the entries CCU and UC,  these must be OK, if not check the serial and parallel communication from the computer to the two controller, choose CCD->Activate CCD Controller or UC->Activate UC Controller from the menu
5. reload the CCD database from the menu: CCD->Reload database
6. switch on the CCD voltages from the menu:  CCD->Voltages on
7. flush the CCD's with the large button labeled Flush CCD
8. check the temperatures and the LN2 status of all channels in the status window (should be green or OK)
9. setup the observer data
10. the system is now READY!

Hallo