The Apogee KX-4 camera is now operating on the Singer telescope in place of the Kodak Megaplus 4.2. This camera is operated for the time being by a program somewhat similar to the moonglow program used for the Apogee earthshine camera.
There are actually two programs involved in the KX-4 operation. One, apsunkx4, actually runs the camera while the other, camera, runs the display. The commands to set exposure time, interval time, and so forth are given to apsunkx4, while commands controlling the size of the image display, the scaling and orientation of the image, display of image histograms, and so forth are given to camera.
To prepare to use the camera, open a terminal window on moon (if one isn't open already) and issue the following commands:
daytime
This command tells moon that the KX-4 camera is to be used. There are two cameras on moon and the current Apogee software can only control one at a time. If you don't give this command you may end up trying to control the earthshine camera with the apsunkx4 program, which won't work very well. Next type
apsunkx4
This will start up both apsunkx4 and camera. You will see "Camera Busy" in the window for camera when it starts up. This is normal. Now press (CR) (the return key). You should see a list of commands for apsunkx4. For example, to set the exposure time you type
set exp nn
where nn is the length of the exposure in milliseconds. All commands are ended by typing (CR), including the q command to stop continuous mode.
The KX-4 has a thermoelectric cooler. The cooler should be used to make the temperature stable and to reduce the dark current. Once the temperature is set, the CCD controller card will keep the CCD at that temperature whether the program is running or not. There are two ways to set the temperature. The
temp nn
command will set the temperature to nn degrees C. If the temperature is more than 5 degrees different from the current CCD temperature, the program will not accept the new temperature. This is to keep the temperature from being changed too quickly. The
auto_temp
command will allow you to enter any temperature the camera will accept. The program will automatically gradually change the temperature until the desired setting is reached. Other commands cannot be given while auto_temp is working. You can type CTRL-C to stop auto_temp.
The commands
temp -1000
will turn off the cooler. THIS COMMAND SHOULD NOT BE USED UNLESS THE TEMPERATURE IS WITHIN 5 DEGREES OF AMBIENT. Otherwise the life of the camera will be shortened. THE COOLER SHOULD BE TURNED OFF BEFORE THE COMPUTER IS SHUT DOWN. THE COMPUTER MUST BE SHUT DOWN BEFORE THE CAMERA CAN BE DISCONNECTED FROM THE COMPUTER.
To have the camera take images at a given rate, use the following commands.
set exp nn
sets the exposure time to nn milliseconds.
set interval tt
sets the interval time to tt seconds.
do_run
starts the camera. There is a short delay until the first picture is taken.
stop_run
stops the camera.
The display is adjusted using the menus on the camera program. The Tools menu contains options for setting the display. The Basics selection from Tools includes options for the size of the image. Note that for correct solar orientation the "Filp T/B" button must be selected.
The continuous mode will take images as fast as the camera will read them out (about once every 5 or 6 seconds) and will not save them. Use
do_cont
to start continuous mode and
q
to stop continuous mode. There are two things to remember here. First, the q command must be followed by a (CR) just like all the other commands. Second, the camera will take a couple more images after you've given the q command before it stops. This is normal.
When you are ready to take the synoptic data, stop the movie or continuous modes if they are running with stop_run or q and give the command
synoptic The system will get ready to take the centered synoptic image. When you are ready to take the image, press (CR). Wait for the image to display, then press (CR) again to accept it or n to reject it. Once you have the centered image, give the
synoptic
command again. The system will prompt you to press (CR) again and, after you press it, will take the dark frame.
To take the off-center frames for the flat field, continue giving the
synoptic
command. I suggest using the continuous mode to make sure the image offset is what you want. You do this by typing do_cont to start the continous mode and typing q to stop it before typing synoptic again. Remember the camera takes about 5 or 6 seconds to read out, so you have to be patient when moving the telescope.
If you have already taken the synoptic data and have to take them again because the processing was unsatisfactory, just type
synoptic
again. The system will ask whether you want to take the images over again, overwriting the old ones. If you want to save the old images, open another terminal window and copy them somewhere else on the system before giving the synoptic command. The images are found in /data/daytime/synoptic.
Use the status command to show the status of the camera.
To stop the camera when done for the day, use stop_run to stop the movie mode if is running or q to stop the continuous mode if it is running. The
exit
commmand will stop both the apsunkx4 and camera programs. It is OK to leave the CCD cooler on overnight.