Welcome to the AviStack homepage!

AviStack is a freeware tool for astronomy that registers, stacks and processes movies and image sequences.


Update of 29 January 2010: Version 1.81 now available!

For all users: AviStack now available in Italian. Spanish AviStack manual released, thanks to Jesús Navas.


  Get your astronomy weather forecast from:

From Version 1.80, AviStack enables you to read a much wider range of file formats as well as AVI codecs (Windows only!). This is thanks to Ronn Kling's AVI reader DLL/DLM. It makes accessible basically all AVI codecs installed on your computer.

This is how to proceed:

  1. Download and install AviStack 1.81.
  2. Goto Ronn's homepage where you will find the DLL/DLM download.
  3. Click on "krsgravi" and download krsgravi.zip. Then unzip it.
  4. Place KRSgrAVI.dll and KRSgrAVI.dlm in your AviStack program directory.
  5. Run AviStack.

If you want to read MOVs (e.g. Canon DSLR HD videos) and MPEGs with AviStack, you will additionally have to install the AviSynth frame server. Ronn's DLL will then take care that most MOVs and MPEGs are read properly.


As always: Before downloading and using AviStack, read the End User License Agreement!



If you have any trouble/recommendations, please, give feedback via the AviStack Group or contact me!


Example Images

For example images, visit my homepage or look here.


Many thanks to everyone who was involved in beta testing AviStack 1.8x!

Michael Theusner