To what extent are we bound to artist intent when we adapt their work? 

I am inclined to think that our freedom here is not unlimited. It is very very broad of course, and we want to avoid slavish imitation, and of course we need to take modern sensibilities into account. But I do not think we can ignore context completely. It behooves us to understand what a work meant to it's own time and place, before we force our own tastes and values upon it. 

Context matters. Realism is all fine and good, but I'm not convinced a graphic gang-rape scene really enriched "the William Tell Overture". I think Rossini's intention here should have been more carefully considered. 

Performers of operas and plays do indeed need to try new things, and do indeed have a difficult task in making old works relevant to modern audiences, but I'm not sure they have tabula rasa. It can only be made so relateable. Let's face it: Opera, and Symphonic music, and ELizabethan drama are not immediately relateable to modern audiences. If they were, they would be filled with pop music, and spoken in modern English. At some point it needs to be acknowledged that these are older forms, created in different times for different audiences. Good art is eternal, but it is also of its time, and we ignore it at our peril. 

I suppose the issue comes up most often in adaptations of Shakespeare. Most productions these days I would wager (though it'd be a dangerous wager to make considering how often they're performed) opt for some kind of anachronistic performance, setting them in recognizably modern, or at least much more recent settings. I'm not sure exactly why - every director and set designer probably has a different idea, but I suspect it has something to do with Shakespeare's perceived universality (that, and the extreme ugliness of Elizabethan fashions). 

This raises all kind of issues. Some interpretations work, and some do not. I enjoyed Baz Lehrman's "Romeo and Juliet" but despised Julie Taymar's "Titus". I felt one respected the subject matter and the other did not.I had no trouble with the introduction of guns into a tale of gang-violence, but saw no point in the addition of arcade machines and disco balls in the latter. It would be absurd to suggest that every future production should be just like the Globe Theatre's strictly historical enactments (an argument applied by some Baroque musicians to their own art), but does that mean we can do absolutely anything we want with the text? Could Romeo and Juliet work in an age of texting? Could Henry V be set in Paschendale, Normandy, or Falujah, or the Star Wars universe? (Let's try it and find out!)

I suppose it depends. Let's look at two plays. "Hamlet" is almost always modernized. "Macbeth" far less so. (And don't be a smart alec and go on about some indie college production you just got back from. . .). I think it's because many people recognize that time and place is important to "Macbeth" in a way that it isn't for "Hamlet". Nobody cares that Hamlet is set in Medieval Denmark; it is generally understood that the core of the play lies elsewhere, in the psychology of the character. So Hamlet can be adapted to just about any setting imaginable and lose none of its power.

Macbeth though. . . I saw one updated Machbeth, (with Patrick Stewart) set in what looked like Soviet Russia. In grim bunkers and military hospitals. It looked like one of the "Hostel" movies. It didn't work. For one thing, the Soviet setting imposes on it a whole set of associations that aren't really supported by the text. I think that matters. 

Akira Kurosawa moved the action to feudal Japan in "Throne of Blood", and it was brilliant. THe Scottish play worked ideally amongst the samurai. So the "place" is clearly not what matters, but the "time" - it was still very much an ancient, historical, mysterious setting. 

Macbeth needs to take place in a world where ghosts exist, and where witch's prophesies are taken seriously. Hamlet saw ghosts as well, but Hamlet spends most of the play pretending to be insane, and is widely suspected to not have been pretending. Hamlet has been performed as a one act monologue by the schizophrenic inmate of a lunatic asylum. It's a modern interpretation, but the text does support this interpretation. Hamlet is so much about psychology and inner struggle that its ghosts can be easily brought into the modern era. But Macbeth's ghosts are actually ghosts, and need an age fit for ghosts. If psychology lay at the heart of Hamlet, superstition is the core of Macbeth, and does not lend itself to more enlightened ages. The Dark Age is the proper home for Macbeth. It could be Scotland's or Japan's, but either way should be in a time where such a tale could be believed, when the social constraints of civilization were that much weaker, and race memories of the caves and trees that much fresher. If it can be set in dark, misty forests, so much the better. You could never set Macbeth in a discotheque. Or, you shouldn't anyway.

When we we adapt a text, we submit ourselves to the will of the text, not the other way around. Hubris will not serve us well.

(Of course, the moment I post all this, no fewer than two major anachronistic Macbeths pop up in London, and I found yet a third in my local library. Well, I never said it never happened. . .)