Originally Posted by Albert Loewy (Post 59871)

If areas are sinking consistently, that means you didn't use enough medium in those places. You may use a retouch varnish, after the fact. Since retouch varnishes usually contain Damar, some prefer to mix up their own oiling-out medium instead. Take your normal media, in my case, 1 part Stand Oil/ 2 1/2 parts turp. Mix up a media twice as lean, 1S/5T. Use that to oil her out. The faded colors should instantly come right out.
Wait at least a year before applying final varnish. I've been led to believe that another layer of paint ought not be put over the final varnish.