Differences

This shows you the differences between two versions of the page.

--- courses:ast100:ip [2025/12/07 22:28] – removed asad
+++ courses:ast100:ip [2025/12/10 09:49] (current) – asad
@@ Line 1: / Line 1: @@
+====== Image processing for astrophotography ======
+The data and the Siril script can be found in this google drive folder: https://drive.google.com/drive/folders/1vW2kqUQbHBEYf9KfGACMadruxLblsAUO
+===== Processing and Stacking Monochrome Astronomical Images in Siril =====
+==== 1. Downloading and Installing Siril ====
+  * Go to: https://siril.org/download/
+  * Download the installer for your operating system.
+  * Install:
+    * Windows → run the .exe
+    * macOS → open .dmg and move Siril to Applications
+    * Linux → use AppImage or package manager
+----
+==== 2. Setting Up StarNet++ and Script ====
+=== 2.1 Download StarNet++ ===
+  * Download StarNet++ from the provided link.
+  * Extract the folder to a known location (example: C:/Siril/Starnet2/).
+=== 2.2 Install the Siril Script (.ssf) ===
+  * Download the provided script.
+  * Place it in your Siril scripts directory:
+    * Windows → C:\Users\<user>\AppData\Local\Siril\scripts\
+    * macOS → ~/Library/Application Support/siril/scripts/
+    * Linux → ~/.config/siril/scripts/
+----
+==== 3. Downloading the Data ====
+  * Download the dataset from the provided Drive link.
+  * Extract everything into a working directory.
+----
+==== 4. Sorting the Data into Filter Folders ====
+The data is already calibrated. Only light frames are provided.
+Create the following folders:
+  * **L/**
+  * **R/**
+  * **G/**
+  * **B/**
+  * **HA/**
+Move each filter’s images into its respective folder.
+----
+==== 5. Opening the Project in Siril ====
+  * Open Siril.
+  * Click the **Home (house) icon** → top-left corner.
+  * Navigate to the parent directory that contains the subfolders: L, R, G, B, HA.
+  * Select that directory.
+----
+==== 6. Running the Preprocessing Script ====
+  * Go to **Scripts** tab.
+  * Select the installed script.
+  * Siril begins checking and preparing images.
+  * Preview window appears.
+To change preview mode:
+  * Bottom bar → switch **Linear** ⇄ **AutoStretch**.
+----
+==== 7. Background Extraction ====
+  * Go to **Process → Background Extraction**.
+  * Place sample points on dark, empty background areas.
+  * Ensure no stars, nebula, or bright zones under the points.
+  * Click **Apply** (Extract Background).
+----
+==== 8. Plate Solving (Astrometry) ====
+  * Go to **Analysis → Astrometry → Plate Solver**.
+  * Enter:
+    * Focal length
+    * Pixel size
+    * Camera sensor information
+  * These values are visible under **Image Information**.
+  * Click **Solve**.
+----
+==== 9. Color Calibration ====
+=== 9.1 Photometric Color Calibration (SPCC) ===
+  * Go to **Color → Photometric Color Calibration**.
+  * If Gaia server is down → download Gaia catalog locally from Siril’s database manager.
+  * Run SPCC.
+==== 10. Stretching the Image ====
+Stretch *before* star removal for best results.
+  * Go to **Image Processing → Histogram Transformation**.
+  * Use **AutoStretch** or adjust:
+    * Black point
+    * Mid-level
+    * White point
+  * Apply the stretch.
+----
+==== 11. Star Removal with StarNet++ ====
+  * Go to **Process → Star Removal → StarNet++**.
+  * Set the StarNet++ executable path if prompted.
+  * Enable:
+    * “Create starless image”
+    * “Create star mask”
+  * Run StarNet++.
+Output:
+  * One starless image
+  * One stars-only image
+----
+==== 12. Post-Processing ====
+=== 12.1 Color Saturation ===
+  * Go to **Color → Saturation**.
+  * Increase moderately.
+=== 12.2 Curves ===
+  * Go to **Image Processing → Curves**.
+  * Adjust luminance/RGB to preference.
+----
+==== 13. Re-Adding Stars ====
+  * Go to **Image Processing → Star Processing → star recomposition**.
+  * Combine:
+    ``starless + stars``
+  * Apply to produce the final image.
+----
+==== 14. Saving the Final Image ====
+  * Go to **File → Save As**.
+  * Export as TIFF, PNG, or FITS.