A plugin for NINA that dynamically selects an optimal target for imaging, allowing for unattended, multi-night, multi-target automated imaging.

This plugin draws heavy inspiration from Tom Palmer's Target Scheduler plugin and shares a number of similar features. However, DS is designed for the more advanced user who is looking for more control over their sequencer. DS requires prior experience with NINA and the advanced sequencer to get working properly. However, once functioning, it allows you to queue up a whole season's worth of targets and it will automatically choose a target every night, take exposures, filter out bad exposures, and take flats when a project is completed.

DS is designed for setups that are hosted at a permanent or remote observatory, heavily focusing on long-term automation. Although it will certainly work on a mobile setup, an electronic rotator, filter wheel, and flat panel are recommend to get the most out of this plugin.

DS adds a series of sequencer instructions such as DS: Center and Rotate and DS: Take Exposure that act similarly to vanilla NINA instructions but are more dynamic, hence the name of the plugin. When configured correctly, DS selects a project from a pool of projects and takes images automatically as defined by the JSON project files.

The use of JSON project files allow for easy integration with other tools. Simple scripts can be written to convert lists of coordinates and rotations to the JSON format required by DS. This may be particularly helpful when planning large mosaics or sky surveys. There is no graphical configuration interface within NINA for DS, everything is done via project JSON files.

DISCLAIMER This plugin is in early stages of development and comes with absolutely no warranty. The author of this plugin is not responsible for any potential damage to equipment or lost imaging time. Use at your own risk.

After running NINA with DynamicSequencer for the first time, files and directories are generated in the Documents\DynamicSequencer directory. This includes the Projects directory, Logs directory, and settings.json file.

Global plugin settings are located in the settings.json file. Settings are listed in the table below. The file generated by the plugin uses default values.

1. Create a project JSON file in the projects directory, it can have any name.
2. Edit the JSON file with the items from the following table, each project will have its own JSON file. All properties are required. If a file does not contain a particular property, the property will be populated automatically with its default value.

WARNING There are currently no checks for valid project JSON. All JSON files within the Projects directory are loaded by the plugin and assumed to be valid. No warnings may be generated and unexpected behavior, including infinite error loops and crashes, may result from an invalid JSON file.

The following project file defines an Andromeda Galaxy LRGBHa project:

{
  "name": "M31",
  "active": true,
  "priority": 0,
  "ditherEvery": 1,
  "minimumAltitude": 0.0,
  "horizonOffset": 5.0,
  "centerTargets": true,
  "useMechanicalRotation": true,
  "flatType": "UPON_PROJECT_COMPLETION",
  "flatAmount": 30,
  "takeFlatsOverride": false,
  "imageGrader": {
    "minStars": 100,
    "maxHFR": 2.0,
    "maxGuideError": 1.0
  },
  "targetSelectionPriority": [
    "COMPLETION",
    "ALTITUDE"
  ],
  "targets": [
    {
      "name": "Panel 1",
      "rightAscension": 11.0029,
      "declination": 41.3956,
      "skyRotation": 55.0,
      "mechanicalRotation": -1.0,
      "takeFlatsOverride": false,
      "exposureSelectionPriority": [
        "SELECTIVITY",
        "N_COMPLETION"
      ],
      "exposures": [
        {
          "filter": "L",
          "exposureTime": 300.0,
          "gain": 100,
          "offset": 30,
          "binning": 1,
          "moonSeparationAngle": 140.0,
          "moonSeparationWidth": 10,
          "requiredAmount": 120,
          "acceptedAmount": 0
        },
        {
          "filter": "R",
          "exposureTime": 300.0,
          "gain": 100,
          "offset": 30,
          "binning": 1,
          "moonSeparationAngle": 140.0,
          "moonSeparationWidth": 10,
          "requiredAmount": 60,
          "acceptedAmount": 0
        },
        {
          "filter": "G",
          "exposureTime": 300.0,
          "gain": 100,
          "offset": 30,
          "binning": 1,
          "moonSeparationAngle": 140.0,
          "moonSeparationWidth": 10,
          "requiredAmount": 60,
          "acceptedAmount": 0
        },
        {
          "filter": "B",
          "exposureTime": 300.0,
          "gain": 100,
          "offset": 30,
          "binning": 1,
          "moonSeparationAngle": 140.0,
          "moonSeparationWidth": 10,
          "requiredAmount": 60,
          "acceptedAmount": 0
        },
        {
          "filter": "Ha",
          "exposureTime": 600.0,
          "gain": 100,
          "offset": 30,
          "binning": 1,
          "moonSeparationAngle": 120.0,
          "moonSeparationWidth": 10,
          "requiredAmount": 30,
          "acceptedAmount": 0
        }
      ]
    }
  ]
}

• The Planner Engine selects an optimal project, target, and exposure from the pool every time any DS instruction is executed.
• The engine will maintain a memory of the previous project and target and will always prioritize those as long as they are valid. This memory may be manually cleared at any time with DS: Reset Memory.
• A project is deemed to be valid when: it is active, not completed, and contains at least one valid target.
• A target is deemed to be valid when: is it not completed, above the minimum altitude and custom horizon, and contains at least one valid exposure.
• An exposure is deemed to be valid when: it is not completed and is sufficiently far away from the moon.
• Project, target, and exposure rankings can be fully customized with the projectSelectionPriority, targetSelectionPriority, and exposureSelectionPriority settings, respectively.

Criteria available for projectSelectionPriority:

This setting does nothing if only one project is available/active/valid.

Criteria available for targetSelectionPriority:

This setting does nothing if only one target is available/valid.

Criteria available for exposureSelectionPriority:

This setting does nothing if only one exposure is available/valid.

The criterion with a lower index in the list takes precedence. If a previous criterion is able to discern two projects/target/exposures, later criteria will not be checked. For example, if projectSelectionPriority is [ "PRIORITY", "COMPLETION" ], the project with a lower priority number will always be selected, given that it is active and valid, regardless of its completion. If two projects have the same priority number, the more completed project will be selective first.

Conversely, if projectSelectionPriority is [ "COMPLETION", "PRIORITY" ], the project that is more completed will always be selected, given that it is active and valid, regardless of priority number. If two projects have the same completion percentage, the project with a higher priority number will be selected first.

If all listed criteria are the same for all projects, a random project will be chosen.

WARNING Target selection behavior is undefined if the lists are left blank.

• DS keeps an internal log of all exposures that have passed image grading to determine which project, target, and/or filter requires flats to be taken. DS: Take Trained Flats takes those flats and clears the log.
• Dynamic flats will only function if all of the following prerequisites are satisfied: flatAmount greater than zero, useMechanicalRotation = true, target.mechanicalRotation is a valid value, and trained flat presets are available for the specific filter, gain, and binning. If any of the prerequisites are not met, that particular project / target / exposure will be ignored.
• Once the criterion specified in the flatType field is satisfied, flatAmount number of flats will be taken for each applicable project, target, and exposure upon the execution of the DS: Take Trained Flats instruction. For example, if flatType = "UPON_PROJECT_COMPLETION" and flatAmount = 30 for a particular project, after the project reaches 100% completion the next time DS: Take Trained Flats is executed, 30 flats will be taken for every target and exposure combination in this project.
• Only one option can be chosen for flatType.
• If takeFlatsOverride is set to true, flatAmount number of flats will be taken for each applicable project, target, and exposure upon the execution of the DS: Take Trained Flats instruction regardless.

Options available for flatType:

WARNING Automatic flat system behavior is undefined if the option is left blank.

• Frames that are rejected do not increment the acceptedAmount field.
• There is no option to turn off image grading, it can be effectively disabled by setting the grading criteria such as "minStars": -1.
• Frames that are rejected are not deleted. Instead, the Sequence Title attribute of the frame metadata is edited to have - REJECTED at the end. If NINA is configured to include the $$SEQUENCETITLE$$ attribute in the image file pattern setting, the image's name will change accordingly. For example, if a frame is usually saved as M31/Panel 1/Ha_2000_01_01.fits, a rejected frame will be M31 - REJECTED/Panel 1/Ha_2000_01_01.fits.

All Dynamic Sequencer items can be identified by a name which starts with DS:. All the sequencer instructions and conditions from this plugin can be used in the same way as any other instruction from NINA.

Slew, centers, and rotates to the optimal target. Current project and current target is saved in memory. The planning engine is "sticky", it will always prioritize the current project and current target if they are incomplete and available. This prevents the planner from bouncing back and forth between two or more targets, wasting valuable time. Will do nothing if the current target did not change. Behavior similar to vanilla NINA's Slew, Center, and Rotate can be achieved by setting centerTargets = true and useMechanicalRotation = false.

Clears memory of current project and current target. The planning engine will reselect the optimal target with no "stickiness" during the next run. This should be run at the end of every night. May be run more frequently if shooting mosaics.

Takes one exposure in accordance to the exposure plan selected by the planning engine.

WARNING DS: Take Exposure makes no attempt to check if the imaging setup is in the correct configuration (mount pointed at correct object, filter wheel set to correct filter, flat panel open, etc.). As long as the frame taken passes image grading, it will increment the acceptedAmount field for the target it thinks its pointed at. For example, an imaging setup is previously imaging M31, and the Planner Engine selects a new target M42, if for whatever reason the mount did not slew properly or the DS: Center and Rotate instruction was skipped, the subsequent DS: Take Exposure instruction will increment the acceptedAmount field for M42 and place the frame into the M42 folder while it is actually still shooting M31. The same behavior is true for the filter wheel. Hence, it is generally good practice to set the On error option to Skip current instruction set within NINA for all DS-related instructions.

Switches filter in accordance to the exposure plan selected by the planning engine.

Sends a dither command to the guiding software when conditions are met. Configurable with the ditherEvery setting. This instruction will only send a dither command if the number of frames shot in any filter since the last dither/slew exceeds the setting. For example, when ditherEvery = 1, a series of frames may look something like this: SHO'SHO'SHO or L'L'LRGB'L'L'LRGB. Or when ditherEvery = 2 it may look like: SHOSHO'SHOSHO or LL'LRGBL'LLRGB'LL.

Checks the internal flat log for required flats. Configured with flatType and flatAmount fields. It is recommended to run this instruction once a day during daytime. The instruction will be skipped if there is nothing to do.

Waits indefinitely until at least one target is returned from the planning engine. Note: the planning engine does not filter for sun altitude, so this should be used along with Wait if Sun Altitude or Wait for Time.

Loops indefinitely while at least one target is returned from the planning engine. Note: the planning engine does not filter for sun altitude, so this should be used along with Loop Until Sun Altitude or Loop Until Time.

Loops indefinitely while at least one project is active. Completed projects are automatically set to inactive.

An example sequence:

• Added option to override flats for each individual target

• Now targeting NINA 3.0.0.3005-rc
• Redesigned dynamic flat system

• Replaced target selection priority logic
• Added new moon separation priority criterion
• Targets and exposures list order within project JSON files is now static
• Project JSON files now have default values

• Bumped to .NET 8 to target NINA 3.0.0.1085-nightly
• Project coordinates property now use J2000 epoch
• Normal (non-debug) log files are now slightly more detailed
• Fixed 180 degree rotation logic
• Fixed potential target mismatch between DynamicCenterAndRotate and DynamicExposure

• Projects are now located under Documents\DynamicSequencer\Projects
• Added settings.json file
• Added logger and option to enable debug logging

• Added option to disable dithering
• Fixed AF trigger issue with DynamicExposure (again)

• Ported to NINA 3
• Versioning is now NINA_MAJOR.MAJOR.MINOR.PATCH

• Added save mechanical rotation feature
• Added sequencer item validations
• Added DS: Take Trained Flats
• Updated README introduction section

• Added DS: Dither
• Projects, targets, and exposures now have unique ids

• Fixed AF trigger issue with DynamicExposure

• Added image grader
• Fixed meridian flip timing issue

• Added DS: Loop While Project Available

• Added planning engine
• Added moon separation filter
• Added DS: Center and Rotate
• Added DS: Reset Memory
• Added DS: Take Exposure
• Added DS: Switch Filter
• Added DS: Wait Until Target Available
• Added DS: Loop While Target Available