stacking – PekDar – Astrophotography Engineering

Astro Pixel Processor – Basic Tutorial (Step‑by‑Step Guide)

PekDar — Thu, 03 Dec 2020 17:22:56 +0000

The main goal of this Astro Pixel Processor tutorial is to provide you, with the ability to quickly stack photos using the APP program, in the shortest possible time with minimal the baggage of knowledge need. I share with you what I know. I have gained experience using the APP program on my own. Remember that each photo of collected lights is different and the examples below, will not necessarily work for your collected photo lights. You should always look for the optimal settings and solutions for each lights. Please, note that I am not the Developer of the APP (Astro Pixel Processor), but only I’m user like you. I don’t know answer to every question that bothers you. Nor am I any representative of the APP Developer or its publisher. APP provides flexible stacking algorithms compared to DSS, supports mosaics, gradient correction, and multi‑session integration. A great balance between simplicity and power. Why choose APP? APP stands out compared to other programs (e.g., DSS, PixInsight) thanks to: Flexible stacking algorithms (multi‑session integration). Support for mosaics and gradient correction.Intuitive interface and automatic calibration. It’s a great balance between simplicity and power – perfect for astrophotographers who want more than DSS without the steep learning curve of PixInsight. APP Preconfiguration Click on CFG button From the drop-down list, set the amount of RAM you want to allocate for use with APP. The rule is simple, more = better. After setting the desired amount of memory, click on OK and that’s it. Lights processing – ATIK Horizon CMOS color camera The Light files are made with “ATIK Horizon color camera” with the filter used in the optical path. We will be processing a photo from a single session so, the following settings of individual tabs are in the given configuration. Run the APP program (my version is 1.081). Shortly after starting a window will appear in which you have to enter the path, to the working directory. Preferably the same directory that contains Lights files for stacking. On the left side of the program window, under the tabs, uncheck two options: • Multi-Channel / Filter processing • Multi-Session processing In the Enter DeepSky object name: text box, enter the name of the object that was photographed. After selected files are loaded, the counter for Lights will change from 0 to the number, of files that we have indicated for loading. In my example, there are 89 files. 0) RAW/FITS ATTENTION! if your photo material was made with a camera, set pattern to supported. pattern set to supported turn off force Bayer/X-Trans CFA Click on the tab 0) RAW / FITS. It is very important to know the sensor type of the camera, on which the photos were taken. In the case of ATIK Horizon it is GRBG and such should be set for pattern from the list of available types. We enable the force Bayer / X-Trans CFA option, the other options are not changed. 1) LOAD Go back to the 1) LOAD tab and click the Light button to load the Light photo files. Notice the counter with status 0 to the right behind the buttons. In the file selection window, select the files you want to load and click the Open button. After the selected files are loaded, the counter for Light will change from 0 to the number of files, that we have indicated for loading. In my example, there are 89 files. At the very bottom of the program window, there is a preview of the list of loaded files. It is worth reading the description of each column – helpful and necessary information. Now repeat the process of loading files for the types: Flat, Dark, DarkFlat and Bias. You can skip all calibration frames or the missing type, then you should take into account that the quality of the photo will be worse. If you already have previously generated MasterFlat, MasterDark, MasterDarkFlat, MasterBias and BadPixelMap files for the Flat, Dark, DarkFlat and Bias file groups, that you want to use, you can load them now and skip the Master… regeneration process it saves a lot of time in the whole photo stacking process. WARNING! Remember that Master files generated from a given group belong to the Lights files photo session. The exceptions to this rule are BadPixelMap and MasterBias. 2) CALIBRATE Plenty of options available here, you can get a little overwhelming. We will be focusing only on a few specific options following my example. I think that the following description will be applicable in most cases of the collected lights files. Most options have a default value that we won’t change except for a few. Turn on: scale MasterDarkFlat scale MasterDark Now it’s time to generate Masters calibration files. Click on the create Masters & assign to Lights button. WARNING! – If you have already loaded Master calibration files, click the (re-) assign Masters to Lights button, this will assign the lights files to the calibration files. APP – Calibration frames options After creating the Master photos, you can see what they look like. This is very important. The quality of stacked the final photo depends on the quality of Master files preparation. In the file view list (at the bottom of the program window), you will see the Master files created. To view the mentioned files, just click 2x LMB on their name to load them to preview. Below is a sample of how my Master files look like. They are generally not bad and they are suitable as a calibration files for lights files. BadPixelMap – zoom 80% MasterDark – zoom 80% 3) ANALYZE STARS We do not change the default value. 4) REGISTER Most of the default options are set correctly and we will not change them. Let’s go to the next tab. 5) NORMALIZE Configure the individual options as described below. It is possible that some options, are already set by default as defined

AutoStakkert! and Lucky Imaging: The Mathematical Battle Against Atmosphere

PekDar — Fri, 15 May 2020 06:27:12 +0000

AutoStakkert 2

Learn the best settings and a step-by-step process to stack your Lunar light frames in AutoStakkert and achieve sharper, high-resolution Moon images.

The Seeing Problem

Why is a single DSLR photo of the Moon rarely perfectly sharp? The culprit is Earth’s atmosphere. Air masses of different temperatures mix, creating turbulence that acts like lenses with varying focal lengths. This phenomenon is called seeing. In classical photography (long exposures), seeing blurs details. The engineering solution is the Lucky Imaging technique.

Mechanism: Statistics and Video

Instead of a single photo, we record thousands of video frames with very short exposure times (milliseconds). Statistically, within a second, there are moments when the atmosphere “freezes” for a fraction of a time and becomes perfectly transparent. The role of AutoStakkert! is to analyze each of the thousands of frames, grade their quality (sharpness), and select only the “lucky” ones (e.g., the best 10-20%).

At first impression, the AutoStakkert user interface does not seem easy to use. However, after getting to know the key options and understanding how the program works, its interface not more to be a secret. We will go through the stacking procedure, processing sample of Moon light frames, which I collected in the early spring of this year.

AutoStakkert! on Linux: Installation via Wine and PlayOnLinux

PekDar — Fri, 08 May 2020 19:02:24 +0000

AutoStakkert Linux installation

Windows is Not Required Many astrophotographers keep a Windows partition strictly for one piece of software: AutoStakkert!. This is an unjustified waste of resources. The stacking engine of this software runs perfectly in a Linux environment, often offering better RAM management than Microsoft’s native system due to the lightweight nature of the Linux kernel.

How It Works: Wine Is Not an Emulator

The key to success is Wine (acronym: Wine Is Not an Emulator). It is a compatibility layer that translates Windows API calls into POSIX (Linux) instructions on the fly. This allows the application to run with near-native performance, without the overhead of emulating an entire operating system. The PlayOnLinux (POL) tool described in this guide is used to easily manage so-called Wine “prefixes”—isolated containers with specific configurations.

Why this works?

AutoStakkert! is a portable app — no classic MSI installer.
Wine supports most API calls required by AS!3/AS!4.
Linux filesystems (ext4, btrfs) handle large SER/AVI files better than NTFS.

Shortened deployment Guide (Universal Method)

Since AutoStakkert! does not have a classic installer (it is a “portable” application), the process in PlayOnLinux differs slightly from the norm:

Download: Get the latest stable version (AS!3 or AS!4) as a ZIP archive.
POL Configuration: Select “Install a program,” then “Install a non-listed program.”
Virtual Drive Creation: Choose “Create a new virtual drive” (preferably 64-bit architecture to handle large SER/AVI video files).
No Installer: When POL asks for the installation file, point it to the AutoStakkert .exe. The program won’t “install” into the system registry but will be executed within the Wine directory structure.
Shortcut: Finally, create a shortcut directly to AutoStakkert.exe.

Performance and Memory

When working with massive files from planetary cameras (often 50-100 GB), Linux file systems (ext4 or btrfs) handle I/O operations significantly better than NTFS. Stacking proceeds smoothly, provided that the Wine configuration has been allocated sufficient video memory access.

Warnings

Use Wine ≥ 6.x — older versions may cause errors.
Don’t copy files into system directories — keep them inside the Wine prefix.
Test with a small SER file before processing large sessions.