Jump to content

Banner.jpg.5ed196c1e70861ebc79109e023c96067.jpg

Creating a Lunar Mosaic from Avi files...issue


UkSpacenut
 Share

Recommended Posts

Hey everyone. Have previously stumbled across this forum when searching for answers to questions, have finally made an account. 

Last night I shot the moon for a couple of hours. I took around 10x3 minute videos and captured a little over 80,000 frames. My aim was to then create a lunar mosaic image but I have never done this before, and my technical ability seems to be adding to the confusion. 

So to give some context, I used an ASI120MCS planetary camera through an 8" Skywatcher Skyliner 200p dobsonian. 

I have read that ideally you would use a tracking mount to record sections of the moon at a time, however I sadly don't have that luxury. 

I instead let the moon drift across the field of view and I'm pretty confident that among the 80,000 frames I have all the pieces of the moon as a whole. 

 

What I'm now having issues with is how to break down these Avi files into frames which then can be used to create a mosaic. I need a "for dummies" guide ae thats what I'm feeling like currently. 

 

Thank you in advance for any assistance you may be able to provide. :)

Link to comment
Share on other sites

Hi UkSpacenut. I've done this often, although I don't let it drift as much. I've use a Mak on an EQ3 mount so can carefully track it a little bit, roughly by hand. 

My suggested workflow would be as follows:

  1. Use Pipp (Planetary Image Pre-processor - https://sites.google.com/site/astropipp/) to split your AVI files into segments, you can do a preliminary stretch (this will help in the next step) to set which range of frames to export, so with a bit of trial and error you can batch it all up into your separate avi files by eye. You are not aligning at this point, just splitting the file into your regions.
  2. Once you have your separate files for each region, run them separately through Pipp to align them using the solar/lunar close-up preset. This is why prelim stretch in step 1 is important, it'll help the software to do it's alignment. You can set what it aligns on with a little alignment box - choose a unique, high contrast feature (I've had mixed results testing to determine the best size box). Also, set your 'Region of interest' - the FOV you want to output. You can also tell Pipp to sort by quality (use the 'original' setting) and keep only the best 25%. Don't run this step as a batch, do an individual run for each file output from step 1 - because you'll need to change your ROI and alignment box for each set of frames. Also make sure you account for overlap (20% ideal) and the drift.
  3. Don't output the final, aligned images to AVI, save as SER files and install SER player from the same site. That way you can manually inspect the results, frame by frame, and bin any frames that could be problematic for Autostakkert/Registax/Siril when you come to stacking the results. (mainly looking for frames that jump around due to alignment feature errors - if there are too many, run it again, choosing a different alignment feature)
  4. Stack however you like.
  5. Use IMPPG (https://greatattractor.github.io/imppg/) to do some deconvolution and sharpening etc.
  6. Enjoy the fruits of your labour.
Edited by johnfosteruk
  • Like 1
Link to comment
Share on other sites

15 minutes ago, johnfosteruk said:

Hi UkSpacenut. I've done this often, although I don't let it drift as much. I've use a Mak on an EQ3 mount so can carefully track it a little bit, roughly by hand. 

My suggested workflow would be as follows:

  1. Use Pipp (Planetary Image Pre-processor - https://sites.google.com/site/astropipp/) to split your AVI files into segments, you can do a preliminary stretch (this will help in the next step) to set which range of frames to export, so with a bit of trial and error you can batch it all up into your separate avi files by eye. You are not aligning at this point, just splitting the file into your regions.
  2. Once you have your separate files for each region, run them separately through Pipp to align them using the solar/lunar close-up preset. This is why prelim stretch in step 1 is important, it'll help the software to do it's alignment. You can set what it aligns on with a little alignment box - choose a unique, high contrast feature (I've had mixed results testing to determine the best size box). Also, set your 'Region of interest' - the FOV you want to output. You can also tell Pipp to sort by quality (use the 'original' setting) and keep only the best 25%. Don't run this step as a batch, do an individual run for each file output from step 1 - because you'll need to change your ROI and alignment box for each set of frames. Also make sure you account for overlap (20% ideal) and the drift.
  3. Don't output the final, aligned images to AVI, save as SER files and install SER player from the same site. That way you can manually inspect the results, frame by frame, and bin any frames that could be problematic for Autostakkert/Registax/Siril when you come to stacking the results. (mainly looking for frames that jump around due to alignment feature errors - if there are too many, run it again, choosing a different alignment feature)
  4. Stack however you like.
  5. Use IMPPG (https://greatattractor.github.io/imppg/) to do some deconvolution and sharpening etc.
  6. Enjoy the fruits of your labour.

Thank you for this! Just a question on the 1st step, what files should I export them as in the processing stage? 

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.