I think DBE thinks it is a nebula or something. I guess I'll just crop it down.
No DBE doesn't think it's a nebula or something. DBE is a typical PI thing. It only works well when you understand HOW to use it.
You whistle up DBE. Click reset at the bottom, it covers the image with a cross. Click generate, DBE works better when you understand how to set the different parameters for that. That creates a grid of sampling points (where the samples are not stars). You maybe add a few more sampling points manually. Set correction to "subtract". Then you drop the DBE on the image. PI gives you a background image, what it's subtracting. Stretch it, examine it, and you can see if you need to adjust the sampling points.
I am not kidding. That's how you get DBE to work well.
You've just had a great learning experience. What you really need to know. PI doesn't magically process better. It gives you a wide array of very adjustable tools so that YOU can process better. IF you know which to use when. And how.
I have hundreds of hours of study and experiment in it. Two 400+ page books. Chapters in other books. A weeklong small (individual attention) class with a world renown PI expert, Vicent Peris. Peris spent maybe half an hour on DBE, showing us how to develop sampling points, and what good and bad backgrounds looked like. Then had us try it on our personal data, coming around to critique our work.
I don't recommend PI for the majority of beginners. Learning to use it takes too much time, time you need for learning other things.
I recommend Astro Pixel Processor. Much easier. Has an _excellent_ gradient reduction tool that's much easier to use. A numbered workflow that walks you throught the process. As I said, with PI you need to know which tool to use when.
I had imaged for over a year when I tackled PI. This book was absolutely key. I had tried web tutorials and failed miserably.
It is a great learning tool. Walks you through a workflow, with operations of increasing complexity, in a well organized fashion. But, it's not comprehensive. There's only so much you can do with PI in 400+ pages. <smiling, but still not kidding>
If you just follow an Internet website, PI is no better than anything else. To get its value, you need to adapt it to your data. Like by adjusting the sampling parameters/sampling points in DBE. They'll be different for every image. One size definitely doesn't fit all.
Minor point. You use any gradient reduction before stretching. Stretch the data, that distorts it, and makes the calculations work poorly.
Edited by bobzeq25, 24 May 2022 - 10:41 PM.