From Master Light to Magic

Introduction

With your stacked master light ready, you’re entering one of the most important stages of the workflow.

This is where your raw stack begins its transformation into a polished astrophotograph — cleaning the data, preserving signal, and preparing for colour calibration.

1️⃣ Open Your Master Light

Open your stacked .xisf or .fits file created by WBPP or your stacking software.

💡 Pro Tip: If you have multiple masters (RGB, Luminance), process them one at a time.

2️⃣ Save Your Project Immediately

Save your project straight away using File → Save Project As.

💡 Save often and duplicate your image after major steps to create safe rollback points.

3️⃣ Inspect and Crop the Frame

Zoom in and check for edge artefacts or registration issues.

• Use Dynamic Crop only where needed
• Keep the crop minimal to preserve field of view

4️⃣ Remove Gradients with GraXpert

Run GraXpert to correct vignetting and gradients.

• Use AI mode with high quality
• Ensure real structures are preserved

5️⃣ Analyse Star Quality

Evaluate your stars before sharpening:

1. Extract CIEL* channel
2. Open FWHMEccentricity
3. Run analysis
4. Check results:
   • Lower FWHM = sharper stars
   • 0.4–0.5 eccentricity = round stars

6️⃣ Create an Accurate PSF

For best sharpening results:

1. Use luminance or CIEL*
2. Open DynamicPSF
3. Select clean, unsaturated stars
4. Measure PSF
5. Enter manually in BlurXterminator

7️⃣ Run BlurXterminator

• Start around ~0.5 sharpening
• Avoid ringing artefacts
• Keep star profiles natural

8️⃣ Apply NoiseXterminator

Run noise reduction while still linear:

• Use default or ~0.45 strength
• Preserve faint detail
• Improve SNR without over-smoothing

9️⃣ Save Your Work

You should now have:

• Cleaned and cropped frame
• Balanced background
• Measured and sharpened stars
• Reduced noise (linear stage)

You are now ready for colour calibration and enhancement.