Well let me try to explain.
I do it because it works!
By changing the exposure I change where the focus points are. When Fiji combines the shots a new deeper image is created. This shot could not have been done as a single image. Perhaps my understanding of what is happening is flawed but my understanding of the outcome is accurate.
I will, if you choose to accept this mission, send you the middle shot of this series in RAW and allow you to try to recreate my shot out of one shot.
Actually I will open that offer up to anyone in CiC.
Brian
PS 16 not 19