Contents - Index

Equipment

This section is used to provide CCDAutoPilot with essential information about your equipment.  This data must be entered correctly to insure proper automation control of your observatory.  Much of this information will be automatically obtained by the Initialize button but should it fail, you will need to enter it manually.  See Equipment Setup for hardware-specific information as it becomes available.



Imager
  • Pixel size: This is the size of the pixels used in your imager.  If your chosen camera control application properly provides the information, it will be obtained automatically with the Initialize button.  If not, you must enter it manually.
  • Telescope focal length: This is the focal length of your imaging telescope.  If you have properly entered it in the defaults/settings section of your camera control program, it will be obtained automatically with the Initialize button.
  • Unbinned image scale: You need to provide an estimate here.  You can enter pixel size and focal length estimates here and hit the calculate button to get a rough estimate.  The Initialize button will refine all data.
  • Gain: If provided by the camera control program, this data will be filled in.  Otherwise it can be entered manually.
  • Auto Bias:  If this is checked, the average bias level will be measured and added to the specified target ADU for sky flats.  The higher the average bias level of your camera, the more necessary this is to insure best accuracy.  Of course you will still need to subtract a master bias from the resultant sky flats, best made from many bias frames to insure lowest noise.  If your average bias level is consistent or if your camera does not have a shutter, you should uncheck Auto and enter your average bias value.  This will allow unattended operation to progress without having to cover the telescope for the automatic bias frame acquisition.
  • Sub-Frame: When checked, the Get button is activated to allow acquiring a suitable sub-frame.  When cleared, the full frame of the sensor is used.

    Sub-framing is useful any time you want to limit the pixels used in your imaging sensor.  It may be that you have a larger sensor than can be fully illuminated by your optical system.  By using sub-framing, you only take and download the data you will ultimately use.  Once defined, this sub-frame information is stored in the system profile for subsequent reuse.  This sub-frame definition is applied identically to light frames, dark and bias frames and flat frames.  Any precision slews use a plate solve that is taken from the center of the sub-frame.  

    To define a sub-frame, follow the instructions presented when you hit the Get button.  They will be different, depending on your camera control program.  The sub-frame data reported below may be slightly different than that shown by the camera control program.  This is done to insure binned to unbinned integer relationships, i.e. no "fractional" pixels.

    For Maxim:

     

    For CCDSoft:

     

    Once you have made your selection, you will be given an opportunity to save it to your system profile: 



    In either case, if you wish change the defined sub-frame, you will be presented with the old and new with an opportunity to accept or reject the new one:



    If you select No, the previous sub-frame information will be maintained.  Sub-framing will be calculated proportionally for any binned sub-frames.  The sub-framing data is always reported unbinned.

    When sub-framing is active for a session, the default file name will end in "Sub", just before ".fit".  Here are some typical default file names when sub-framing is used:
    Light frame: Clear169W_M101_00062Sub.fit
    Dark frame: -15Dark600s1x1_070528_00076Sub.fit
    Bias frame: -15Bias1x1_070528_00074Sub.fit
    Flat frame: Clear_Flat169w_M101_00102Sub.fit

    Warnings will be given in the Session review and log file that you are using sub-framing.  A typical warning at the start of a session will look like this:
    22:55:01 Root save path: \\Reggie\astronomy\
    22:55:01 System profile: C:\Astronomy\_Documents\U16M_DG070524.app
    22:55:01 Target List: C:\Astronomy\_Documents\M101.xml
    22:55:01 Start sequence number: 61
    22:55:01 
    22:55:01 
    22:55:01 WARNING: Sub-framed exposures selected and being used.
    22:55:02 
    22:55:02 
    22:55:02 Light Frames
    22:55:02 Telescope connected

    You can see what sub-frame information you are using by the Review Setup button on the Run Session page.  A typical entry will look like this when sub-framing is used:
    WARNING: Sub-framed exposures used for imaging
       Note: these are unbinned values
       X start: 342
       Y start: 342
       Width: 3402
       Height: 3402


    Guider
  • Pixel size: This is the size of the pixels used in your guider.  If your chosen camera control application properly provides the information, it will be obtained automatically with the Initialize button.  If not, you must enter it manually.
  • Guide scope focal length: This is the focal length of your guide telescope.  If you are using the self-guided mode, this will be the same as the Telescope focal length, above.  It will be entered automatically by the Initialize button.
  • Guide rate: This is the guiding rate as a factor of sidereal tracking and must be entered manually.  This is usually a defined value for your mount and can be obtained by consulting your mount's documentation.  This is an essential parameter and must be filled in for proper operation.
  • Guider binning: This is the guider binning you normally use.  If your chosen camera application properly provides this information, it will be obtained automatically by the Initialize button
  • Mount: Specify Equatorial if you are using a German Equatorial Mount such as a Paramount, Astro-Physics or Losmandy for example.  Specify Fork if you are using a Meade or Celestron fork mount for example.
  • Guider: Select Self guided or Self guidedR if you are using a guider that shares the telescope with the imager.  This would be appropriate for most SBIG cameras and off-axis guider (OAG) systems.  For SBIG systems using the internal guide sensor, Self guided is the appropriate setting.  If you are using an OAG then Self guidedR is appropriate.  This can be determined experimentally if necessary - see below.  Guide scope is selected when you have another telescope for you guider.  Unguided is selected for unguided imaging.
  • Initialize: This function determines a number of key parameters for your system for subsequent seamless automation.  A plate solving method is an absolute necessity for initialization.  Before hitting this button, your camera, telescope, plate solving method and rotator (if used) must be connected.  For guided operation, you must have centered a guide star on your guider and have run one manual calibration at your chosen binning, insuring the guide star stays on the chip for all movements and actually moves properly in each direction, just as you would do for a normal calibration.  The guider should be oriented at an angle of 10° or more to the RA/Dec axes, as opposed to lining up with one of the cardinal points.  Your guider binning should be set in your camera control program before initialization.  The telescope can be pointed to either side of the meridian and at any Dec, although a lower Dec. will give better results.  Dec does not need to be 0 for example.  Make sure you have properly set the Plate Solve Exposure settings (below).  When ready, hit the Initialize button.  The status bar on the lower right reports progress and completion.  When Initialization is complete, you will be prompted to save the results to a profile.  You should choose a descriptive name for this profile so you can easily identify the conditions.  For example, I use 14RCselfguidedRIMG, which tells me it was for my 14RC scope, self-guided with the R option and my IMG camera.  This technique is helpful if you have multiple setups.  CCDSoft users should have separate profiles for guiding with DirectGuide and Camera Relays as the internal operations are different.  If you switch between Maxim and CCDSoft, then the same system profile can be used, consistent with the CCDSoft DirectGuide or Camera Relays consideration.  You will need to initialize both Maxim and CCDSoft if you use both.

    The initialize function calibrates your system for accurate Position Angle (PA) entry.  Your unbinned image scale is refined.  Essential guider parameters appropriate to your camera control program are developed and optimized.  After a successful initialize, you will never need to calibrate your guider again, no matter where you go in the sky in RA, Dec, and PA, as long as your equipment does not change!  Your guiding calibration is determined by internal algorithms that are optimized for your specific coordinates.

    You need to reinitialize when you:
  • Change your system, represented by your mount guide rate, camera, guider and optical system.
  • Change your camera control system
  • Change your guider type
  • Change your guider binning
  • Change between DirectGuide and Camera Relays in CCDSoft
  • Rotate your guider relative to your camera
  • Lose your home setting with the RCOS PIR

    If you have an instrument rotator, there is a convenient way to initialize.
    1. Set the Guider to unguided and initialize.  This will calibrate the rotator to the position angle.
    2. Go to the target page.  Using the FOV Center target as described here, translate and rotate the FOVI so that a guide star is in the guider FOV.
    3. Slew to the target with precision slew checked.  Once this process completes, you should have the guide star on the guider chip.
    4. Run a guider calibration with your camera control program to insure the guide star stays on the chip for all movements
    5. Now initialize again and the guider parameters needed for CCDAuoPilot to develop optimized vectors are collected.


    Self guided note
    The best way to determine whether you should use Self Guide or Self GuideR is a simple test.  After successfully initializing as described above, do a short run on the present location to insure guiding runs appropriately, i.e. the guide star stays in the box and the guide errors are reasonable.  Then, rotate the camera by 90°, recenter a guide star and repeat the run.  The guide star should stay in the box and the guide errors should remain reasonable.  If the guide star tends to wander out of the box, then stop the run, select Self GuideR and repeat the same run.  This time the guide star should stay in the box with reasonable guide errors.  If you still have problems, rotate the guide camera by 180° and then try Self Guide and Self GuideR again.