Stacking by ephemeris not starfield

Posted by AIJPJC on Nov 08, 2019; 11:41pm
URL: http://astroimagej.170.s1.nabble.com/Stacking-by-ephemeris-not-starfield-tp1250.html

Hello,

I was wondering if it is possible to align/stack images such that a specific and different RA/DEC is chosen in each image for overlay on the next image (I am NOT trying to align the stars I want them to end up streaked).

I have a set of plate solved images from a system that is currently unable to track an ephemeris. So all my images have the same center coordinate (besides error) tracking sidereally over a one minute dwell.

My target is too dim to see in each image, so when I try to pick a point using the WCS tool the annulus jumps around to a bright set of pixels, not my desired RA/DEC coordinate.

The theory is that if I can align the target RA/DEC for each image and stack, my object might jump out while turning the starfield into streaks. I know aligning by a single point could have additional issues rotationally. I don’t really care though, I’m just trying to make my target pop out using its known ephemeris from JPL Horizons (under the assumption it’s somehow hidden deep in the data).

This would be a lot simpler if I can fix my system to track an ephemeris again! Thanks in advance.