Landscape Astrophotography - PT Gui - Issues with Night Sky Stitching Seams (Visible and Latent)

[Hugh Brown]

Landscape Astrophotography - PT Gui - Issues with Night Sky Stitching Seams (Visible and Latent)

I’ve been running into an issue with stitching seams in my night sky panoramas.

I am shooting as follows:

1. 10 position with a circa 10 - 12 frame stack per position.
2. Generally at least a 30 percent overlap.
3. ISO 12800 at f2.8 and 13 second exposures.

The issue has been occurring so that there have been visible stitching seams (but not right across the panorama) and latent stitching seams (again not right across the panorama) that become apparent with subsequent stretching.

I have been exporting the stitched layers individually from PT Gui rather than blending the layers inside PT Gui - so the stitch seams happen when I apply auto-blend in Photoshop.

My exposures are equalised across the panorama pre stitch so I don’t think that is a causative factor.

I want to continue exporting individual layers within the panorama to enable other corrective measures in Photoshop if necessary (pre autoblend) such as where there are stitching steps in the horizon.

How do I avoid this happening?  And what is the corrective course of action if it does happen?