KalaMama:
Black: All hairs are black from root to tip. Shaved face is black.
Blue: All hairs are the same shade of grey from root to tip. (Puppies are born black and their coat gradually changes to grey) Shaved face is grey.
Poodle in front is blue, poodle in back is black.
Blue poodle:
Bad Black: Most of the coat is black with many white hairs mixed in. From a distance, when you can't see the colour of the individual hairs, the dog looks grey. Shaved face is black.
Can't find a picture of this, sorry.
Most black dogs get white hairs as they age. A black poodle is a bad black when it starts getting a lot of white hairs at a young age.
Anyone, please correct me if I'm wrong.

I hope this helps.