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                                                                           CCDS Acquisition Camera User’s Manual

10

One exception to this is that on clear, moonless nights it may be difficult to see the slit for
short exposure times.  Binning 3x3 may allow you to see the slit more easily.

Note that the “Vertical N Binning” and “1xN, 2xN, 3xN” binning options are used for
spectroscopy, and should not be used in this application.

7.

 

Saving an Image

One obvious advantage to the new acquisition system is that you can now save an image
from the CCD and use it later for alignment purposes, to measure the seeing, etc.

To save the current image open in CCDOps, simply press the “Save” button on the
toolbar.  This will open up a Windows “Save As” box.  Type a name in the File Name
box.  The default data type should be FITS format, although you may change it if you
wish.  Save the image in “C:\data” and click Save (you may create a subdirectory if you
wish).  This directory is mounted on the linux workstation as /data/slit24 at the 2.4m and
as /data/slit13 at the 1.3m.  You may then access these data from the linux workstation.
You may also print the image to the printer in the computer room.

Summary of Contents for Acquisition Camera CCDS

Page 1: ...yboard and mouse The control pc lives in the computer room on the small red rack and is clearly marked This upgrade should be in all respects an improvement to the functionality of CCDS and should not represent much of a change of usage for the observer In particular all of the existing optics were retained in this upgrade the only hardware that was replaced was in fact the camera itself Please no...

Page 2: ...61E Format 512x512 20x20 _m pixels Cooling Single stage TEC Readout Time 1 second Gain 1 8 e DN Dark Current 1 DN s pixel 0 C Read Noise 6 6 DN Bias 130 DN Saturation 65 K DN At the 2 4m Pixel Scale 0 23 arcsec pixel Field of View 1 97 arcmin At the 1 3m Pixel Scale 0 41 arcsec pixel Field of View 3 54 arcmin ...

Page 3: ...e do not set it too low as this will cause the CCD to overheat Click OK to close the setup box 4 Click Focus on the toolbar and enter an integration time Click OK to begin taking exposures The camera reads out in 1 second so exposures shorter than 1 second give roughly a 1 Hz update rate 5 Make sure the cooling capacity gauge lower right corner of desktop reads less than 60 If not raise the system...

Page 4: ...u will need to reboot the control computer and may need to reinstall the drivers If you need to unplug the USB cable for some reason first close CCDOps then proceed Once the CCDOps startup screen goes away you should see the CCDOps toolbar see Figure 1 Click on EstLink in the CCDOps toolbar this will establish a link with the camera It should take about 5 seconds if it takes longer than this or di...

Page 5: ...y cause damage to the camera Figure 3 CCDOps status bar from lower left corner of CCDOps desktop This example shows from left to right an established link normal unbinned high resolution imaging and the temperature setpoint set to 0 19 degrees C The cooling capacity gauge reads 58 capacity and there is a red filter in the beam For normal operation all other settings should also be as shown in Figu...

Page 6: ...ther settings in this dialog box as they are shown in Figure 4 Click OK and the system will begin taking images immediately Stop the focus sequence by clicking on Focus in the Toolbar or by hitting Esc To change the exposure time stop the focus sequence and begin it again each time you start a focus sequence the system will ask for an exposure length Pause focus mode with the Pause button in the F...

Page 7: ...screen Figure 5 shows a sample image Figure 5 Image taken with the CCDS acquisition camera on a photometric moonless night through the clear filter You can clearly see the slit in this 10 second exposure The star inside the circle is V 19 mag CCDOps also allows the observer to change the display parameters of the downloaded images In the Contrast pop up box that appears once an image is downloaded...

Page 8: ...ilter Performance measured on a clear night with no moon Note that objects are detectable with a S N 10 the above exposure times are an overestimate of the exposure time for minimum detection 4 Filters If your target is very bright or very red or blue you may wish to place a filter in the beam The ST 9 comes equipped with a five position filter wheel populated with a clear red green and blue filte...

Page 9: ...sing the Focus button again type in a longer integration time in the window that appears Note that very long integration times e g longer than 60 seconds may require dark frame subtraction to deal with the dark current in the device If you are not worried about the update rate you may turn on dark frame subtraction by checking the Dark Frame box in the Focus pop up window This is probably undesira...

Page 10: ...an image from the CCD and use it later for alignment purposes to measure the seeing etc To save the current image open in CCDOps simply press the Save button on the toolbar This will open up a Windows Save As box Type a name in the File Name box The default data type should be FITS format although you may change it if you wish Save the image in C data and click Save you may create a subdirectory i...

Page 11: ...ontrol computer through the telescope wrap with a USB cable Since this cable is very long it is converted to CAT5 ethernet cable and back to USB with devices called ICRON USB to ethernet converter boxes Please note that this does not mean that the camera is connected to the internet it is not It is conceivable that these devices have become unplugged Make certain that each box one on the telescope...

Page 12: ...ges A pop up window will ask you for the CCDS password CCDS is the name of the administrator account on this machine Type ccds in the password field Please make sure once you complete this process that you are logged in as Visitor for the rest of your observing session The Wizard will ask you if you want Windows Update to search for software Select No not this time The Wizard will ask you what you...

Page 13: ...nual 13 The Wizard will allow you to choose your search and install options Select Don t search I will choose The Wizard will ask you to select the device driver for this hardware Highlight the first driver on the list then click Next ...

Page 14: ...Camera User s Manual 14 A pop up will appear warning about Windows compatibility issues Select Continue Anyway Select Finish to complete the wizard You may now re open CCDOps and establish a link to the camera as normal ...

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