Session Phases: Light Frames

When the Light Frames tab is selected at the top of the page, the data portion of the session plan is displayed. The upper half is concerned with targets and the lower half with the exposure series taken for a given target.  This topic is concerned with the Target half.

Light Frames

The grid shows the target information.  Column headings are:
  • Target: A unique target name.  Duplicate names in the database are not allowed.
  • Active: When checked, the target is active and will be a part of the session plan.
  • R.A.: The right ascension of the target, formatted in hours, minutes and seconds.
  • Dec.: The declination of the target, formatted in signed degrees, minutes and seconds.
  • PA: The position angle of the target, formatted in degrees.
  • Loop_Series: Defines how many times the set of series will be repeated or looped
  • Guide_Factor: Defines a delay that will be introduced after starting the guider and before the exposure starts.  This delay is equal to the Guide_Factor times the Guide Time entered in the series.  Normally this is not needed with the Automatic Guide Star Recovery.
  • First Start Time: This is the time and date that data acquisition for the target will start. This is the actual exposure start time. If scheduling between multiple targets allows, the mount will slew to the target, perform precision slew and/or focus up to 10 minutes before starting the first exposure. If there is more time between targets, the mount will either stay on the prior target with tracking off or park the mount, depending on the Mount Options selected on the Options page/The mount will wait on station until the user specified start time and will start the first exposure precisely at that start time.
  • First End Time: This is the time and data that data acquisition for the target is forecast to end.
  • RA Rate: The RA tracking rate in arc-sec./sec. Default value is 0.
  • Dec Rate: The Dec tracking rate in arc-sec./sec. Default value is 0.

    Note: RA Rate and Dec Rate are made visible by slewing the horizontal scroll bar in the target grid. These rates are added automatically when using the Get function for non-sidereal objects such as comets, asteroids and satellites. For example, If you enter "ISON" in the Get box  and press Get and the comet database is loaded in TheSky, the coordinate data and tracking rates for ISON will be loaded into the target list. These values can also be added manually by editing the appropriate cells in the target grid.
  • : Moves the selected target up in the target list.
  • : Moves the selected target down in the target list.
  • Update: Updates the target database.  This should be hit whenever editing is completed with one target and its associated series and before changing to another target or the edits may be lost.
  • From FIT: Allows entering the coordinates of an existing FIT file by plate solving it. Upon successful solution, the solution is shown in the status bar along with the time to solve in seconds in parentheses. After selecting an appropriate template, the File Name and coordinate information is entered into the target database.  The target name can be edited as needed. Once the template is entered, the Exposure Series will be populated.  Be sure to hit the Update button to enter the target and series into the database.
  • Get: Get is only functional when TheSky is used as the planetarium server.  Enter a target to search for by entering its name in the space provided and hit the Get button. If it exists in TheSky6's database, the coordinates will be transferred into the Target list. If Get is hit with no entry, the RA and Dec of the FOVI's center in TheSky6 will be entered. The PA of the FOVI will also be entered. It is the FOVI center that determines the transferred coordinates, not any selected star or object. If you want to get a selected star in TheSky's window, move the FOVI over that object. This is a powerful target framing feature that is described in more detail here. When used in conjunction with a rotator, you can select a suitable guide star using the FOVI and CCDAutoPilot will move the scope and the rotator to those precise coordinates. When adding a target, you are asked for a template.  Please see the Templates topic.  Once the template is entered, the Exposure Series will be populated.  Be sure to hit the Update button to enter the target and series into the database.
  • Mosaic: Used to create a target list from the mosaic function in TheSky (Professional Edition only). With the desired mosaic set up in TheSky, pressing the Mosaic button will bring them into the Target List. Each mosaic element may then be edited by using the Edit Function or Edit Button. If you are doing guided imaging, then you can move the FOV indicator as needed to locate a guide star and replace each Mosaic entry in the target list with an adjusted FOV Center, via the Get button.  When adding mosaic elements, you are asked for a template.  Please see the Templates topic.  Once the template is entered, the Exposure Series will be populated.  Be sure to hit the Update button to enter the target and series into the database.
  • Loop Targets: Defines how many times the list of targets will be repeated in the order given.
  • Skip First Target Slew: If checked, no precision slew is made to the first target the first time.

    Context (Right-Click) Menu

    Right clicking anywhere in this section of the Session page brings up this context menu:

  • Slew to Target: Causes the telescope to slew to the coordinates of the highlighted target.  The slew can be chosen to be either a precision slew, as defined on the Setup page or a simple, uncorrected slew.
  • Center TheSky: When TheSky is used as the planetarium program, this will cause TheSky's star chart to be centered on the target coordinates.
  • Set First Target Start Time to Current Time: Sets the first target start time to the current time, leaving all other times unchanged.
  • Reset Time Gaps Between Active Targets: Removes any time gaps between active targets so that the next target starts right after the preceding active target.
  • Enter Target Coordinates Manually: This will open a window in which you can enter the target name and coordinates manually.  

    The target name must be unique.  RA, Dec. and PA must be in the proper format and can not be blank:

    RA: hh<space>mm<space>ss<decimal>s, eg. 12 34 56.7
    Dec: <sign>dd<space>mm<space>ss, eg -12 34 56
    PA: dd<decimal<d>, e.g. 12.3

    When you enter one field, use the Tab key to move to the next.  You can exit the target entry mode at any time by hitting the ESCape key on the keyboard.  After the PA is properly entered, the Tab or Return key will complete the target entry.  When adding a target, you are asked for a template.  Please see the Templates topic.  Once the template is entered, the Exposure Series will be populated.  Be sure to hit the Update button to enter the target and series into the database.
  • Edit Target List brings up a sub-menu with the following options:

  • Delete Selected Target: Deletes the highlighted target.  The target can also be deleted by hitting the Delete key on the keyboard.
  • Delete All Targets: Deletes all targets in the database.
  • Hide Inactive Targets: Toggles whether or not to hide inactive targets. When checked, inactive targets are hidden; when not checked, inactive targets are visible.
  • Invert Active Selections: It a target is active, it is made inactive; if a target is inactive, it is made active.
  • Duplicate Selected Target: This duplicates the highlighted target. You must rename the duplicate and then select the appropriate template to complete the duplicate target addition.

    Editing Targets

    The Target name can be edited by double-clicking on the target name field.  This will bring up the target edit window.

    Enter the desired target name.  CCDAutoPilot will check the database in case that name already exists.

    All other fields can be edited by clicking on them and simply typing the desired change.  For the first start time field, clicking on it and then double-clicking will bring up a calendar so that you may adjust the starting date as well as time.  

    When finished editing the target row, be sure to hit the Update button.

    Info Window

    The Session info window is helpful in planning your session.  In the above example, you can see the ephemerides info for the selected target, M65.  The East and West times corresponding to the time at which the target is at the altitude shown to the left.  So if you have an obstructed view to the east that limits your lowest altitude to 55, set this value and you will see the time at which the M65 rises above that altitude.  If you have a clear east and west horizons but don't want to image below a certain altitude, check the Equal box and you can simply scroll the upper (E) box.  The (W) input box will track it. The east and west times will track the scrolled altitude limits.

    Note: Hovering the mouse over an active target's name will show the mid-point of the light exposure time as a tooltip. This is handy if you are trying to center a staircase exposure sequence in time such that the data acquisition straddles the meridian. Compare this light exposure mid-point to the target transit time shown in the Info window (See below) at left for a given target.

    Sun and moon rise and set times are also listed.  Also, Civil, Nautical and Astronomical twilight times are available.  Since most astronomical cameras are not particularly light tight for daylight operation, it is generally best to not take darks before civil dusk or after civil dawn.  Astronomical twilight is a guide for sufficiently dark skies to light frames.  It is generally best to not take light frames before astronomical dusk or after astronomical dawn.  There are exceptions of course but these are reasonable guidelines.

    Target Order Management (Professional Version)

    CCDAutoPilot has the ability to change the order of targets in a multiple target database by a combination of dragging and dropping the target row or sorting based on a column header. Target order can also be changed by using the up/down buttons mentioned above.

    A given target row can be moved up or down in the target list first by clicking and releasing on the row header to select it. Make sure one and only one row is highlighted and that the full row is highlighted. Click and release on the desired row again if necessary to highlight it. Then click on the row header again until the drag/drop symbol appears. While holding the left mouse button down, drag the mouse up or down as appropriate to relocate the target row at the desired order. Some experimentation may be required to get a feel for the movement. Once the order is as desired, hit the Update button.

    The target list can also be sorted by clicking on the Column header for Target, Active, RA, Dec and PA. Click once to sort in ascending order. Click again to sort in descending order. Once the order is as desired, hit the Update button.

    After any change to the target order, the target start times will need to be reset as desired for the new target order.