Yes, maybe....as we talked about your post of trianaei coerulea, or magenta??? Depends on light ( sun or led), equipment( Nikon, Minolta, Sony or just a cheap phone, as mine)...side by side ,two wercks are almost the same in real....but they came from different sources.
Another difficulties , that there are many-many different form of purpurata all around the world, furthermore many of them are crosses ( eg. schusteriana x werck, or werck x roxo)...how can we make difference among them????