https://visualeducation.com/class/using-filters-flash-for-twilight-cityscapes/

• In this video Karl demonstrates an old darkroom technique for photographing a twilight cityscape that allows you to carefully control the exposure of particular areas of the shot.  Instead of graduated filters, Karl uses ND filters in a creative way to basically create the same effect as burning and dodging, but during a long exposure.  This technique is particularly useful if you’re in an environment where graduated filters don’t block light in the right areas.