Comet Capture Workflow - What Have I Learned?

Christopher Barr

I finally finished processing Comet ZTF https://astrob.in/lrvkgv/0/

I am trying to solidify some lessons learned and I realized I have a lot of unanswered questions.  I really struggled with all aspects of this project from data capture through processing.  I think this can be attributed to a number of things: 

1. First attempt at a comet using multiple exposures from a dedicated astro-camera
2. Completely guessing as to the capture workflow/techniques
3. Improper capture technique undermining image processing workflow
4. Pushing performance envelope on processing computer made PI processing workflow experimentation difficult (i.e. time consuming, lack of timely feedback).  This really inhibits my learning process.

I really tried to follow Adam's PI OSC Comet techniques but Comet Alignment process couldn't seem to work well with my data.  I ended up using a fairly small subset (57 of 240) of my data that the algorithm could interpret.  So a couple questions for the group.

What is the best technique for OSC comet capture?  I believe my approach, which involved unguided 60 second exposures and manually repositioning the comet to keep it in roughly the same position of the frame, was incorrect and prevents PI Comet alignment from being able to interpret the data.  Seems like comet alignment expects the comet to drift through the frame with some predictable trajectory in order to perform its magic.  Should I have set a target somewhere in the middle of the area the comet would drift through and then just guided that target all night while exposing?  Wouldn't this approach limit the total exposure time to the time it takes the comet to drift out of the frame?  Does that matter?  Am I missing something else?

I also use a mono camera (though not on this target).  Are there different answers for that workflow?  Or is it just a matter of ensuring there is enough drift margin to accommodate all the filters are appropriately exposed before it drifts out of frame?

I'd lke to have a go at capturing this one again but by the time I realized my data wasn't great it was too late.  I'll just have to wait for the next one!  Probably there's something that a more experienced PI processor could do with the data.  But I frankly just ran out of patience on this project which left me wanting to know how I could make it easier on myself the next time.

Chris