Image Server on Astro Live Stacker

Concepts

Thu, 11 Jun 2026 00:33:39 +0000

Introduction

By the end of this chapter, the basic concepts of ALS will be familiar to you.

You will understand what ALS does and how it does it.

Stacking

Stacking is the process of combining multiple subs of the same target to generate a more detailed and contrasted image than a single sub.

The quality of the result increases as more subs are used.

Comparison of 8 stacking results
The number of stacked subs is indicated at the top left of each image

A successful session

Thu, 11 Jun 2026 00:33:39 +0000

📘 Introduction

This chapter is your roadmap for running a successful ALS session and monitoring its progress.

It wraps up the presentation of ALS main concepts before you dive into the user interface guide.

⚙️ Setup

Whether you’re shooting DSO live, preparing data for detailed post-processing, or diving into something more artistic, these steps will help you get the best out of ALS every time.

✔️ Choose Your Profile

EAA: For live imaging

main controls

Thu, 11 Jun 2026 00:33:39 +0000

Introduction

During this chapter, you will:

get familiar with ALS main controls
Deepen your knowledge on key features

Overview

The ALS control station is the Main Controls interface panel

Located on the left side of the ALS interface, it organizes the most used controls and displays into sections:

Session

Session controls and status
Stack

Stack controls and stack information
Image Server

Image server controls and status
Image Saver

Image saving tools

Output Tab

Thu, 11 Jun 2026 00:20:09 +0000

The settings governing ALS outputs are presented in the Output tab.

Overview

This tab is divided into 2 sections:

The Output tab in preferences

Save

Here are the output file format, output folders, and autosave function settings

Format

ALS saves the main output images in one of the following formats:

TIFF
PNG
JPEG

Main output file format preferences

Server

Thu, 11 Jun 2026 00:20:09 +0000

Overview

The Server utility module exposes ALS processing results through a lightweight HTTP and WebSocket service.

It is responsible for:

Publishing the latest processed stacking result and session metrics in the configured web folder
Serving the viewer web application (index.html, JavaScript and icons)
Streaming live new-image notifications to connected browsers over WebSockets
Providing a QR-code friendly URL so that tablets or phones can join the session quickly

The module runs in its own asyncio event loop and accepts concurrent browser clients. It never alters the processing pipeline; it only serves the web image written by the Save module.

Concepts

Thu, 11 Jun 2026 00:33:38 +0000

Introduction

By the end of this chapter, the basic concepts of ALS will be familiar to you.

You will understand what ALS does and how it does it.

Stacking

Stacking is the process of combining multiple subs of the same target to generate a more detailed and contrasted image than a single sub.

The quality of the result increases as more subs are used.

Comparison of 8 stacking results
The number of stacked subs is indicated at the top left of each image

A successful session

Thu, 11 Jun 2026 00:33:38 +0000

📘 Introduction

This chapter is your roadmap for running a successful ALS session and monitoring its progress.

It wraps up the presentation of ALS main concepts before you dive into the user interface guide.

⚙️ Setup

Whether you’re shooting DSO live, preparing data for detailed post-processing, or diving into something more artistic, these steps will help you get the best out of ALS every time.

✔️ Choose Your Profile

EAA: For live imaging

main controls

Thu, 11 Jun 2026 00:33:38 +0000

Introduction

During this chapter, you will:

get familiar with ALS main controls
Deepen your knowledge on key features

Overview

The ALS control station is the Main Controls interface panel

Located on the left side of the ALS interface, it organizes the most used controls and displays into sections:

Session

Session controls and status
Stack

Stack controls and stack information
Image Server

Image server controls and status
Image Saver

Image saving tools

Output Tab

Thu, 11 Jun 2026 00:20:09 +0000

The settings governing ALS outputs are presented in the Output tab.

Overview

This tab is divided into 2 sections:

The Output tab in preferences

Save

Here are the output file format, output folders, and autosave function settings.

Format

ALS saves the main output images in one of the following formats:

Server

Thu, 11 Jun 2026 00:20:09 +0000

Overview

The Server utility module exposes ALS processing results through a lightweight HTTP and WebSocket service.

It is responsible for:

Publishing the latest processed stacking result and session metrics in the configured web folder
Serving the viewer web application (index.html, JavaScript and icons)
Streaming live new-image notifications to connected browsers over WebSockets

The module runs in its own asyncio event loop and accepts concurrent browser clients. It never alters the processing pipeline; it only serves the web image written by the Save module.

Concepts

Thu, 11 Jun 2026 00:33:39 +0000

Introduction

By the end of this chapter, the basic concepts of ALS will be familiar to you.

You will understand what ALS does and how it does it.

Stacking

Stacking is the process of combining multiple subs of the same target to generate a more detailed and contrasted image than a single sub.

The quality of the result increases as more subs are used.

Comparison of 8 stacking results
The number of stacked subs is indicated at the top left of each image

A successful session

Thu, 11 Jun 2026 00:33:39 +0000

📘 Introduction

This chapter is your roadmap for running a successful ALS session and monitoring its progress.

It wraps up the presentation of ALS main concepts before you dive into the user interface guide.

⚡ Startup

ALS can be launched either from its graphical interface or directly from the command line, depending on your workflow or automation needs.

Graphical launch:
Simply start ALS as any other application. You’ll land in the main window, ready to configure your session.

main controls

Thu, 11 Jun 2026 00:33:39 +0000

Introduction

During this chapter, you will:

get familiar with ALS main controls
Deepen your knowledge on key features

Overview

The ALS control station is the Main Controls interface panel

Located on the left side of the ALS interface, it organizes the most used controls and displays into sections:

Session

Session controls and status
Stack

Stack controls and stack information
Image Server

Image server controls and status
Image Saver

Image saving tools

Output Tab

Thu, 11 Jun 2026 00:20:09 +0000

The settings governing ALS outputs are presented in the Output tab.

Overview

This tab is divided into 2 sections:

The Output tab in preferences

Save

Here are the output file format, output folders, and autosave function settings.

Format

ALS saves the main output images in one of the following formats:

Server

Thu, 11 Jun 2026 00:20:09 +0000

Overview

The Server utility module exposes ALS processing results through a lightweight HTTP and WebSocket service.

It is responsible for:

Publishing the latest processed stacking result and session metrics in the configured web folder
Serving the viewer web application (index.html, JavaScript and icons)
Streaming live new-image notifications to connected browsers over WebSockets
Providing a QR-code friendly URL so that tablets or phones can join the session quickly

The module runs in its own asyncio event loop and accepts concurrent browser clients. It never alters the processing pipeline; it only serves the web image written by the Save module.