In the above video, Adobe’s Russell Brown shows us how to combine multiple nighttime exposures together with Dr. Brown’s Stack-O-Matic script using Adobe Camera Raw and Photoshop CC. By automatically creating layers set to lighten the layers are stacked with star trails revealed as you import them into Photoshop.
You can download the Stack-O-Matic script here on Russell Brown’s website.
How does Stack-O-Matic compare to the built-in Load Files into Stack?
This sounds like Frankestein.