Mosaic allignment issue

[peonic]

Does anyone use APP for stictching mosaics together?

 

I took a 4 panel of the Heart nebula last night - used NINA to generate the sequence - everything appeared to shoot OK.  I followed a tutorial on the APP site for building the mosaic, and I've had an issue where the bottom 2 panels won't allign correctly in the middle (vertically) - but everything else seems to line up OK. It's annoying, because I was rather please with the rest of the result!

 

Attached is the final image (reduced x.7) and a crop of the affected issue.  Has anyone seen this before? Not sure if it's a data issue, or a "me not knowing how to use APP correctly" issue.

 

Chris

[peonic]

Answering my own question here:

 

There's a great demonstration of the Photometric Mosaic Script on the Astro Imaging Channel on YouTube that sorted this right out - and without too much messing around either!