PixInsight process stages using current scripts and tools (Jan 2026)

Some new scripts have become available recently which supersede older and more laborious methods of narrowband processing. This list outlines the various stages.

1. Blink through all frames.
2. Stack all frames in Weighted Batch Pre-Processing (WBPP)
3. If necessary use one of the gradient correction tools such as Graxpert or the native PixInsight Gradient Correction tool on each of the component images (S,H and O).
4. Blur Xterminator at default settings (alter if necessary based on characteristics of the data.)
5. Multi Scale Adaptive Stretch Stretch each component image with this new tool. If the tool isn’t visible after updating PI 1.9.3 go to Process -> Modules -> Install Modules where it should be listed. Click to install the tool which should then appear in the main process menu.
6. Channel Combination
   • S -> R
   • H -> G
   • O -> B
7. Curves - A slight saturation boost at this point can sometimes give better result.
8. Noise Xterminator
9. Star Xterminator to remove stars into separate image.
10. Narrowband normalisation - SHO or HOO give the best results.
11. Use Curves with approriate colour masks to separate and intensify colours in nebulosity.
12. Blur Xterminator on starless image with no star sharpening.
13. EnhanceNebula (optional).
14. DarkStructureEnhance (optional).
15. Curves to adjust black point.
16. In stars image remove any magenta with Scripts -> Utilities -> CorrectMagentaStars.
17. If stars image shows any colour artefacting, try reducing saturation with Curves. The best solution is to shoot RGB stars when capturing data and use this instead of the narrowband stars which will be without true colours.
18. Replace stars with favoured method (see below).
19. Final tweak to Curves as appropriate.

Star replacement methods

Cuiv’s method
Work’s well for most occasions.

With the Starless image and the stars image named as below run this command in Pixelmath:

~((~Starless)*(~stars))

Bill Blanshan script
Use if you want to reduce stars further than normal.

BillsStarReductionMethods_V3.xpsm downloadable from Lukomatico here

Instructions on using Bill Blanshan script