Robin Thanks for the two images you have posted, it dose make me feel better to see those rings in your images as well, I do feel better now.
Doug it is true that Image Plus converts to gray scale, I do know this, and I do use Raw Flat frames before the processing.
Many thanks for your patience, and sorting out this problem for me, which in the end is not really a problem, but the normal end result, but I now know this.
Leon