is no documentation for the specific procedure, however it is possible if you
know what CCDLAB can all do.
You would load the two files into CCDLAB. You can blink between one
and the other image here.
- You can either register the images by shifting if they are simply
translational offset, or, you can cut-out a region of interest around the
star you’re interested in – you would do this for each image, and save the
regions separately. Then you would reload them and perform registration just
on these smaller images. If you right click on the registration button,
then you get an options dialog and you could set the interpolation to
Lanczsos, for higher precision. The registration does compute the centroid
and will shift the image to sub-pixel precision.
- Then save the images again after registration.
- Then load ONE image, and use image subtraction to subtract the
- Now you have the difference, and you could save that as a new file
I could do this for
you really, really quickly if you like – if you supply the images to me and
tell me where the star is. I could even give you a demo over a Teams or Zoom
call if you like.
Feel free to email me at joepostma @ live dot ca