Comet processing using StarTools

[happy-kat]

Thought I would share my experience of processing comet 46P Wirtenan using StarTools.

Initially I was using the comet and stars stack from DSS, this gave good clarity on both elements but meant processing each element whilst on a combined file quite difficult and noisy.

A member then started a thread discussing the shadowy star trails left even on the combined image using DSS and then another member posted a youtube video link to a different technique to process comets using StarTools. Following that process I managed the below but I was not happy with the comet or the star field really. The Life module had been used but the area created for the comet was too big.

Every time I was consistent with Crop / Bin 70% / Wipe / Develop

This was the first attempt

Using the tips learnt in the video I then had another go but this time used other modules to further improve (in my eyes) the image processed.

The combined stack on comet and stars was used for the star field. I had one star field without Capella which I had removed through the heal module and created through a mask and layer subtraction I had another star field with Capella. These two files I layer added, this created a better background with lower noise level.

The combined stack was used for the comet as the comet was in too busy an area to use the comet only stack. I used a mask on the comet and then the life module and isolate to suppress the stars. Next I used the heal module to remove Capella area. Over to the colour module to work on the comet. Saved that image.

Now I could load the star field and then using the layer module I added the comet file and a denoise. 

Many masks were used during the processing and the ones I might use again I saved. I did make a whopper mistake and might go and reprocess the comet again as I forgot to bin the file after I had cropped it so the first go at layers with the stars would not work as the file dimensions did not match. To get around this I binned the processed comet file, but really binning should have been first.

I have noticed that viewing comet images using a tablet or phone the on board viewers are hiding many stars so the images look better on a monitor.

Edit: I did not use the comet only stack because there were too many stars trailing in the comet's glow area that wouldn't go away.

 

[happy-kat]

I should add that the data was captured on a foggy night with 98% Moon so not the best of data to work with and was using an altaz mount. Still best to work the best you can with what you have and keep pushing the processing knowledge 

[Kev M]

Both fantastic in my book, would be more than happy with either

 

 

[happy-kat]

Looking to make a time lapse from my big stack and have broken it into batches of 10 and had hoped to use the one star field for all 11 frames but alas altaz mount strikes,  these two images are approximately 8 minutes apart yet show enough field rotation to rule that idea out.

[Davey-T]

37 minutes ago, happy-kat said:

Looking to make a time lapse from my big stack and have broken it into batches of 10 and had hoped to use the one star field for all 11 frames but alas altaz mount strikes,  these two images are approximately 8 minutes apart yet show enough field rotation to rule that idea out.

I use imppg to align all my time lapse images, really quick and does a great job.

Dave

http://greatattractor.github.io/imppg/

[happy-kat]

Thanks Dave.