Sequencing

The Sequencing screen is where you build and execute automated capture plans. Define one or more targets, configure filters and exposures for each, and let ARIS run the session unattended — slewing between targets, dithering, handling meridian flips, and stopping at astronomical dawn.

Adding Targets

Each sequence is a list of targets. A target is a sky object identified by name and J2000 coordinates (Right Ascension and Declination).

There are two ways to add a target:

• From the Sky Atlas. Find an object on the Plan screen, tap it, and choose Add to Sequence. The name and coordinates are filled in automatically.
• Manually. Tap the add button on the Sequencing screen and enter the target name, RA (in hours/minutes/seconds), and Dec (in degrees/minutes/seconds).

Targets are executed in order from top to bottom. You can reorder them by dragging, or remove them by swiping.

Multi-Filter Configuration

Each target has one or more filter entries. A filter entry defines:

Parameter	Description
Filter	The filter to use: L, R, G, B, Ha, SII, or OIII. Each filter can only appear once per target.
Exposure	Duration of each sub-exposure in seconds.
Frame count	Number of sub-exposures to capture with this filter.
Gain	Camera gain for this filter (useful for narrowband filters that need higher gain).

Tap a target card to expand it and add or edit filter entries. The color-coded filter chips give you a quick visual summary of the plan.

Auto Frame Count

For any filter entry, you can enable Auto Frame Count instead of setting a fixed number of frames. When enabled, ARIS calculates how many exposures fit in the remaining time before astronomical dawn at your location.

The calculation accounts for:

• Exposure duration per frame
• Download time (approximately 5 seconds per frame)
• Dither settling overhead (if dithering is enabled)

Tip

Auto Frame Count is ideal for single-target sessions where you want to image for as long as possible. For multi-target sequences, fixed frame counts give you more predictable time allocation across targets.

Dithering

Dithering shifts the guide camera slightly between exposures to help reduce fixed-pattern noise, hot pixels, and satellite trails during stacking. Each target has independent dither settings:

• Enable/disable — toggle dithering on or off for this target.
• Frame interval — how many exposures to capture between each dither (e.g., every 5 frames).

When dithering is active, ARIS sends the dither command to the guider after the configured number of frames and waits for the guide star to settle before continuing.

Meridian Flip Handling

When a German equatorial mount tracks a target past the meridian, it must physically flip to continue tracking from the other side of the pier. ARIS handles this automatically during a running sequence.

The meridian flip sequence follows these steps:

1. Pre-flip pause. An optional delay before the flip begins, giving any in-progress operation time to complete.

2. Stop guiding. If the guider is running, ARIS stops it before the mount moves.

3. Slew and flip. The mount slews to the target on the opposite side of the pier.

4. Post-flip settling. A configurable delay for the mount to stabilize after the flip.

5. Re-center. Optionally plate-solves and corrects pointing to put the target back in the center of the frame.

6. Resume guiding. If guiding was active before the flip, ARIS restarts and recalibrates the guider.

7. Auto-focus. Optionally runs a focus routine after the flip, since the optical train orientation has changed.

All of these behaviors are configurable in the meridian flip settings. A timeout protects against flips that take too long — if the mount does not complete the maneuver in the allowed time, ARIS aborts the flip and pauses the sequence for you to investigate.

Caution

Meridian flip behavior depends on your mount’s firmware and driver. Test your flip settings with a short sequence before relying on them for an all-night run.

Running a Sequence

Once your targets and filter entries are configured, tap Start to begin the sequence. ARIS will:

1. Slew to the first target.
2. Capture all configured filter entries for that target, cycling through filters as defined.
3. Dither between exposures if enabled.
4. Handle meridian flips as they occur.
5. Move to the next target when the current one is complete.
6. Repeat until all targets are finished or you tap Stop.

While running, the screen shows:

• Overall progress — percentage complete and estimated time remaining.
• Current target — which target is being imaged and how many frames are done.
• Per-filter progress — completed and total frame counts for each filter.
• Status messages — real-time updates (exposing, downloading, dithering, slewing, flipping).

You can pause a running sequence to temporarily halt captures (the current exposure finishes before pausing) and resume to continue where you left off. Stop ends the sequence entirely.

Planning Integration

The Sequencing screen works hand-in-hand with the Sky Atlas. When you find a target on the Plan screen and tap Add to Sequence, ARIS creates a new sequence target pre-filled with the object’s name and coordinates. You can then configure filters and exposures on the Sequencing screen.

Targets added from the Plan screen also display their reference image (if available) and altitude chart on the sequence card, so you can verify visibility without switching screens.

Note

Sequence data is saved automatically and syncs across your devices via Firebase. You can build a sequence on your iPad during the day and run it from the field that night.