I used DSS (DeepSkyStacker) in "Comet mode" to stack. DSS Comet Mode gives you 3 different option on stacking a comet. I used the first 2 methods. The first method allowed me to set the Stars with out trains, so DSS stacked and aligned the stars and ignored the comet. I saved it and then chose the 2nd stack option which was Isolate Comet and ignore stars. This option allowed me to get the detail on the comet however leaving the stars with lots of star trails. I Then had to go into Photoshop and clean up all of the trails and bring out the color and detail of the Comet which took a while.

I then Combined both Stacked images together in Photoshop in Screen Mode. So that a focused Comet was now embedded with the Focused Stars. After some touch up that was pretty much it and here is the Final Image.

This image of Comet C/2019 Y4 took a little over an hour of imaging integration. However the weather was partly cloudy to mostly cloudy around the Philadelphia Area. So I set up my Imaging equipment and Polar aligned as soon as there was some clearing. I knew the clouds would start to roll in, and surely the clouds did for several hours and I did not get a chance to start imaging until very early Sunday morning. Although I had to wait until the clouds cleared I didn't have to stay outside or keep looking out the window instead I have my Imaging telescope hooked up remotely so that I can constantly see the sky conditions through my AutoGuide Scope camera and control my telescope mount and main Imaging camera & gear all from the comfort of inside my house. Astronomy is a great hobby and I highly recommend it to everyone, whether you are a visual observer or into imaging to show others.