Interesting that you say amoral. Of course, you may not be making any kind of intelligent point and not know the difference between amoral and immoral.
But I'll presume you were being specific.
I don't think it's amoral, I think that the whole point behind certain types of porn is that it depicts something immoral. Of course, I don't find the making of pornography in any way wrong, since it all involves consenting adults. But it is often used to portray things that are clearly immoral, eg. rape. Obviously, a consenting actor pretending to rape what is actually a consenting actress is fine, but the act they are portraying is not fine.
So no, (legally made) pornography is in no way immoral as consenting adults can do whatever they like. Sometimes porn contains storylines (if you can call them that, lol) which are clearly immoral. Some is amoral I suppose, if nothing harmful or allegedly harmful is happening and nobody cares about anything!
But that's the point. People do know the difference between art and reality, so there's no more problem in depicting something like rape than depicting murder etc. in a film. If you were going to say that porn itself was immoral you'd have to say it about 'Saw' and 'The Texas Chainsaw Massacre' etc. as well.