Below you will find free videos and other content taken from the instructional library at Adam Block Studios. They are good examples of image processing techniques as well as Adam's style of explaining them. Joining today will give you instant access to many more hours of material like the below.
In addition to the below, you will also find free content on my YouTube channel.
You can also view my presentation on this and other topics from my Astroimaging Channel guest appearance below. I would encourage you to watch the entire presentation... but you can also skip to the part about the technique.
Here is a video from PixInsight Fundamentals on Dynamic Background Extraction. Typically users will throw as many samples as possible on an image and attempt to flatten the field. However, with an approach as shown below, you can reproducibly model your backgrounds with DBE with fewer samples and more quickly. This video is from the "Workflow" example.