The Capture module allows you to do sequence capturing using your camera, it has the following features:

  • Presets: you can save an unlimited amount of presets, which have all the camera settings needed for guiding. You can also choose the scope.
  • Start guiding
  • Preview
  • Advanced Settings
  • Pixmap Image viewer
  • Guide Plot



Creating a sequence


To create a sequence, you should first create a new preset by tapping on the + button next to the preset dropdown box. After filling all the preset settings, you have to tap on the save button on the top-right.


Capture Presets has the following structure:

  1. Preset name
  2. Camera
  3. Frame Type
  4. Exposure
  5. Binning
  6. Format
  7. Filter Wheel
  8. Filter
  9. Temperature
  10. Gain/ISO
  11. Offset


After creating your presets, you can now tap on the preset dropdown in order to select the preset you want, and then tap on Add to Sequence, so the sequence can be added to the sequence list.

In the below example, you can see that there are 3 different jobs in the sequence list as shown by the filter in the beginning of each one. (red, green, and blue)


Sequences have the following structure, displayed through icons for simplicity:

  • Top row
    1. Job Number
    2. Job Progress Bar
    3. Count Progress
    4. Delete Job


  • Bottom row
    1. Filter
    2. Frame Type
    3. Binning
    4. Exposure
    5. Gain/ISO
    6. Offset



After adding the sequences, tap on the Play button under the Progress header to start the sequence.



During the capture, a soft "ding" sound will be played for each capture (you can turn on sounds by switching from Ekos Tab to Settings Tab and then toggling sounds on). After the capture is complete, you will see a notification message that says "CCD capture completed" and a "complete" sound will be played. In the case of the capturing process eing aborted for any reason, an "error" sounds will be played, and a notification message will be shown.



Filter Settings


You can edit filters by tapping on the Filter button. The filter settings page will open and allow you to edit filter settings for each filter of the filter wheel selected in the dropdown menu.


Configure settings for each filter individually:

  • Name: Filter Name
  • Exposure: Set exposure time used when performing focus under this filter. By default, it is set to 1 seconds.
  • Offset: Set relative offsets. Ekos will command a focus offset change if there is a difference between the current and target filter offsets. For example, given the values in the example image to the right, if the curernt filter is set to Red and next filter is Green, then Ekos shall command the focuser to Focus In by +300 ticks. Relative positive focus offsets denote Focus Out while negative values denote Focus In.
  • Auto Focus: Check this option to initial AutoFocus process whenever the filter is changed to this filter.
  • Lock Filter: Set which filter should be set and locked when performing autofocus for this filter.


Let's take an example. Suppose the capture sequence is running and the current filter is Green, so the relative already offset is set to +300. The next image in the sequence uses Hydrogen Alpha (H_Alpha) so before Ekos captures the next frame, the following actions take place:


  • Since Lumonisity is specified as the locked filter and auto-focus is checked, the filter is changed to Lumonosity
  • A focus offset is -300 is applied since the prior filter Green was moved +300 previously.
  • Auto Focus process is initiated.
  • Once Auto Focus is complete, the filter is changed to H_Alpha.
  • A focus offset of -1200 is applied.
  • Capture sequence is resumed.



To edit a filter, tap on it on the panel on the right-side of the page. All of its details will be filled in the panel on the left-side to be edited.



After you edit the filter, tap on the Save button to save the filter settings. The panel on the right-side will shown the new settings for the filter you just edited.



Calibration Settings


Note: You can only edit calibration settings for capture jobs that have the frame type as Bias (B), Dark (D), or Flat (F).


For Flat Field frames, you can set calibration options in order to automate the process. The calibration options are designed to facilitate automatic unattended flat field frame capture. It can also be used for dark and bias frames if desired. If your camera is equipped with a mechanical shutter, then it is not necessary to set calibration settings unless you want to close the dust cover to ensure no light at all passes through the optical tube. For flat fields, you must specify the flat field light source, and then specify the duration of the flat field frame. The duration can be either manual, or based on ADU calculations.


  1. Flat Field Source
    • Manual: The flat light source is manual.
    • Dust Cover with Built-In Flat Light: If using a dust cover with built-in light source (e.g. FlipFlat). For dark and bias frames, close the dust cap before proceeding. For flat frames, close the dust cap and turn on the light source.
    • Dust Cover with External Flat Light: If using a dust cover with external flat light source. For dark and bias frames, close the dust cap before proceeding. For flat frames, open the dust cap and turn on the light source. The external flat light source location is presumed to be the parking location.
    • Wall: Light source is a panel on the observatory wall. Specify the Azimuth and Altitude coordinates of the panel and the mount shall slew there before capturing the flat field frames. If the light panel is controllable from INDI, Ekos shall turn it on/off as required.


  1. Flat Field Duration
    • Manual: Duration is as specified in the Sequence Queue.
    • ADU: Duration is variable until specified ADU is met.


Before the calibration capture process is started, you can request Ekos to park the mount and/or dome. Depending on your flat source selection above, Ekos will use the appropiate flat light source before starting flat frames capture. If ADU is specified, Ekos begins by capturing a couple of preview images to establish the curve required to achieve the desired ADU count. Once an appropiate value is calculated, another capture is taken and ADU is recounted until a satisfactory value is achived.



Limit Settings


Limit settings are applicable to all the images in the sequence queue. When a limit is exceeded, Ekos shall command the appropiate action to remedy the situation as explained below.


  • Guiding Deviation: If checked, it enforces a limit of maximum allowable guiding deviation for the exposure, if autoguiding is used. If the guiding deviation exceeds this limit in arcseconds, it aborts the exposure sequence. It will automatically resume the exposure sequence again once the guiding deviation goes below this limit.
  • Autofocus if HFR exceeds a value: If autofocus is enabled in the focus module and at least one autofocus operation was completed successfully, you can set the maximum acceptable HFR value. If this option is enabled then between consecutive exposures, the HFR value is recalculated, and if found to exceed the maximum acceptable HFR value, then an autofocus operation is automatically triggered. If the autofocus operation is completed successfully, the sequence queue resumes, otherwise the job is aborted.
  • Autofocus if change in temperature exceeds a value: If autofocus is enabled in the focus module and at least one autofocus operation was completed successfully, you can set the maximum acceptable change in temperature value. If this option is enabled then between consecutive exposures, the change in temperature value is recalculated, and if found to exceed the maximum acceptable change in temperature value, then an autofocus operation is automatically triggered. If the autofocus operation is completed successfully, the sequence queue resumes, otherwise the job is aborted.
  • Refocus every x minutes: you can set your focuser to refocus every x minutes. (where x is the amount minutes input by the user)



File Settings


Settings for specifying where captured images are saved to, and how to generate unique file names.


  • Prefix: Specify prefix to append to the generated filename. You may also append the frame type, filter, expose duration, and ISO 8601 timestamp. For example, if you specify Prefix as M45 and checked the Type and Filter checkboxes, and assuming your filter was set to Red and your frame type is Light, the generated file names will be as following:
    • M45_Light_Red_001.fits
    • M45_Light_Red_002.fits
  • If TS was checked, a timestamp will be appended to the filename, e.g.
    • M45_Light_Red_001_2016-11-09T23-47-46.fits
    • M45_Light_Red_002_2016-11-09T23-48-34.fits
  • Script: Specify an optional script to be executed after each capture is complete. The full path of the script must be specified and it must executable. To denote success, the script must return zero as this would allow the sequence to continue. If a non-zero value is returned by the script, the sequence is aborted.
  • Directory: Local directory to save the sequence images to.