The ONLY thing that betrays his being the greatest wizard of all times is his eyes, very bright sparkling blue eyes. And it is in his eyes that the fire of power burns, when he blasts open the door in the fourth book after Moody kidnaps harry, making me shiver in awe of Rowling’s genius ability to create such a untouchable and complete character.
If he wanted to get the truth out of someone, he would simply sit behind his desk, gingerly fold his hands and look over the tip of his glasses straight into their eyes, with his own magnificent, all-knowing, piercing blue eyes.

I am not going to comment on Harris’ performance and I understand that movies are movies and a lot needs to change. But Gambon makes me actually angry when I see him screaming for the attention of children, making a spectacle of extinguishing candles, being physically violent with people, students! Pondering and wondering what to say next in public. He is snarky, bitchy and borderline offensive. Dumbledore knows great or not he is and is certainly not seeking for other people’s opinions on himself. Gambon’s eyes don’t mirror power and wisdom, if anything they show blatant insecurity and a need to prove himself worthy of his decorations.

Everyone has their own opinion, and maybe Gambon is an extraordinary actor and artist. His portrayal of Dumbledore might even be magnificent artistically and emotionally. It is however incomparable and spot on insulting to the Dumbledore that is described in the books, and that is indisputable.

Second, I don’t dislike Gambon’s performance & characterization as Dumbledore simply because it’s different than Harris’. I fully realize that Harris probably couldn’t have played the part going forward. So, no, my problem is completely with Gambon’s portrayal of Dumbledore, his violent, antagonistic tendencies, his total confusion as opposed to the calmness we see from DD until near the end.

Much of the impact of the scenes in HBP & DH were the total twisting of our understanding of Dumbledore as the wise, cool, collected, always in control Professor to the conflicted, manipulative, troubled DD. Don’t really get that from Gambon’s performance. Which is why his scenes in HBP fell flat for me.

If someone has only seen the movies & not read the books, then I could imagine that Gambon’s DD could be considered acceptable. But for those who know the books, I can’t imagine Gambon’s performance truly enhances the character.

So, if you want Gambon to be YOUR Dumbledore, good for you. But for me, Gambon is the despolier of Dumbledore. Oh, and I blame the writers & director too.

I really adored Harris’s Dumbledore in the first two films. He was all-knowing, grandfatherly, always looking out for little Harry. At the time, a real shoo-in for what was on the page.

When Gambon came to the franchise, I was skeptical, but I decided to go along for the ride.

Now, having gone from young teenager to young man over the many years the franchise has grown, I often catch the first two films on TV or throw them in to relive the experience, and what I find surprises me. Richard Harris’s Dumbledore is just as sugar-sweet and paternal as he always was, but seems more like a idealized all-knowing God-like figure than a living, breathing, conflicted person. Gambon on the other hand is driven by action, not “characterization.” As an actor myself, it is a delight to watch Gambon.

Now when I get a hankering to watch a Potter film, I automatically go to Prisoner of Azkaban, Order of the Phoenix, or Half Blood Prince. (It seems we all agree that Goblet of Fire was misdirected and weak in comparison), and I watch specifically for Gambon. The final half hour of Half Blood Prince, as far as I’m concerned, belongs to Michael Gambon as Dumbledore- he doesn’t mug, he doesn’t proclaim, he lives it, takes action, and listens.

We all feel some sort of ownership towards the first incarnation of a beloved character (be it in our minds, on the screen, etc.), so I understand why people have such strong (sometimes vicious) opinions. I think Richard Harris would have been wonderful in the series, and I’m sure his Dumbledore would have grown to be conflicted and complex. However, his untimely demise (R.I.P.) doesn’t give us license to be Gambon haters simply because he is different. Gambon is a fully-capable actor, and to some of us, he is and always has been OUR Dumbledore.

I think multiple interpretations of a character is a valid point, but it does not excuse Gambon in this case. Take Sir Ian Mckellan’s Gandalf for example- although he may have departed from some people’s preconceived notions of the character, he was able to capture the essence of what made people love him.
I do not discredit Gambon as an actor, on the contrary I think he is excellent, I just don’t think he is playing Dumbledore.
I think there is certainly a shift that occurs in Dumbledore as the books progress; Harry grows up and enters the adult world where Dumbledore is able to confide in him as a friend.
The mask of security slips and gone is the omnipotent father figure.
This is where I disagree most with Gambon’s portrayal.
Dumbledore is a man wracked with guilt. He feels responsible for much of the evil in the world and the innocent people killed because of it.
He’s like the fireman who goes back into the burning building 20 times to take people out, but still feels guilty because of the 15 people he did not save.
He is also very clever and, for better or for worse, trusts his own judgement- yet still has the wisdom to question his own actions.
He has an excellent sense of humour and, perhaps most importantly, grand wizard or not, he is utterly self deprecating to the end. He values the lives of each and every one of his students more than his own.

These are aspects of the personality that is Dumbledore. What they do is combine to create a character that you love.
Is Gambon’s Dumbledore flawed then? Definately. Human? Of course Manipulative? Without a doubt. But is he likable? I say no.