I am finding several galaxies that are #two-tone like this one. They have the central core surrounded by a bright disk which is further surrounded by a dim disc. Out of the 900 galaxies that I have classified I have seen 3 like this. I feel that they might be one stage of galaxy evolution or one of the several branches in the evolutionary tree of galaxies.
One of the three had a bar that went out to the edge of the bright disc but no further.
The second had two tight arms which went out to the edge of the dim region.
I shall tag future observations of these with #two-tone.