Comet stacking to eliminate star trailing with Starnet, etc.

Hi All,

It came to mind that if you follow the suggested comet registration and processing steps, but before step 6) INTEGRATE, you one-for-one replace all your subs with ones you ran Starnet on, you don't end up with star trails. Make sure you have backups of your original subs!

You do need to save all your FITS files as TIFF.

To do that I start by pre-processing my FITS files in 2) CALIBRATE (I go ahead and "align channels"), "SAVE (calibrated) Light frames."

From there, under "TOOLS" I batch save the calibrated files as TIFF.

I then start over in APP and load all the calibrated TIFFs and do comet registration workflow as recommended but stop after step 5) NORMAILZE. I then run Starnet on the calibrated files and copy them to the same location with he same names (overwriting the non-Starnet TIFFs), same filenames that I loaded into APP for the steps up to NORMALIZE... then run 6) INTEGRATE without comet recommended settings.

I've done this successfully on Linux. As long as the APP Windows/Mac versions don't keep the files open it should work there too.

Here is the bash shell script to run Starnet on the calibrated TIFF files, which adds "-snet" to each filename. My script is basic (I have saved it as /usr/local/bin/starnet.bash) , and I know it's broken if you have "snet" anywhere in the directory path of your source TIFF files:

##################################

#!/bin/bash

SOURCE_FILE=`realpath $1`
DEST_FILE=`echo $SOURCE_FILE | nawk -F.tiff '{print $1 "-snet.tiff"}'`

# Change directories to where Starnet is:
cd /usr/local/bin/StarNetv2CLI_linux
#echo $SOURCE_FILE $DEST_FILE

#Run Starnet
./starnet++ $SOURCE_FILE $DEST_FILE 256

#################################

The above script works on one file at time, so you need to do something like this from a bash shell if you have a lot of files:

for fits_file in "COMET_C-2021-S3*-snet.tiff" 

   do

    /usr/local/bin/starnet.bash $fits_file

done

Then you copy all those files back to overwrite the original directory/filenames (which is another shell script exercise if you have lots of subs); then you switch back to APP and run 6) INTEGRATE.