Something goes wrong here :? Perhaps I'm missing something?
These are the images of Orion Nebula taken almost two years ago, with exposure times ranging from 1" to 480" with a DSI II. Not fabulous images, but enough to try this new script. :-)
Exposure:1"

Exposure:4"

Exposure:15"

Exposure:30"

Exposure:60"

Exposure:300"

Exposure:480"

Resulting imaged, stretched, like 480" shot.

Default parameters in script