PixInsight - Alignment and Integration

 Image Integration for Stars and Deep Space Objects

updated: updated: 2022-02-11


Image Integration for Stars and Deep Space Objects 

combines all subs from the same area (or frames or pictures) to one single picture and is intended for stars and deep space objects (DSOs).

Repeating measurements is a fundamental technique to analyze and reduce uncertainties in observations. By combining several measurements of the same quantity, random errors tend to cancel out and the observed value can thus be determined with less uncertainty. The image integration task does basically the same thing: combine a set of images of the same subject to improve the signal-to-noise ratio in the resulting image. The ImageIntegration tool allows you to perform this task with a large number of features and resources designed to help you get the best possible result out of your data. 


Process 🡺 All Processes 🡺 Image Integration


Star aligned images with a  â€œ*_c_d_r” postfix from sub folder "4_Registered"


integrated picture, file name like “20210815_M101_ZWOASI294_0000.xisf” into sub folder "5_Integration"

Previous Step

Star Alignment

Next Step

Image Post Processing


https://www.youtube.com/watch?v=UUx-OM3TWs0  (Part 4 - beginning in the middle at minute 14)





Selecting the image input

  • add all registered light frames


Set integration parameters

  • use settings on the right, this will normally bring good results
  • select "Generate drizzle data" when using a OSC camera


Select Pixel Rejection Algorithm (1)

  • Up to 15 frames: use Sigma Clipping
  • Over 15 frames: use Winsorized Sigma Clipping


Pixel Rejection Algorithm (2)

  • User following settings:
    • Sigma Low 3 to 3.4
    • Sigma high: 2.8 to 3
    • Select all files and go.


Large Scale Pixel Rejection

  • not yet tested


Start the Image Integration


Save all final images

Important: At the end of the process you will get 3 files:

  • integration
  • low rejection
  • high rejection

All files must be saved individually for further usage as *.xisf files into the folder "4_Integration"

Save the final frames  to subfolder "4_Integration" using the naming convention:

e.g.:   “20210815_M101_ZWOASI294_0000.xisf”


Next Step: Picture Post Processing

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