With more accurate flats the DBE (Dynamic Background Extraction) module of PixInsight does a far better job of subtracting gradients/light pollution.
Below is a screen capture showing before and after using DBE. This all happens with the data unstretched ie linear and at 32 bit FP. The size of these images are 442 MB fits!
The Screen Transfer Function only stretches the image so it is visible. It does not affect the actual image file.
Here is the final processed image 18MB
http://d1355990.i49.quadrahosting.co...ent_RGB_CF.jpg
Exposures were 15x6 min for each of RGB.
The dust comes up quite well. The stars too well.
Bert