how is the film different from the book?
There are multiple cuts in the film. One such is absence of Quidditch, the Wizarding sport
Harry Potter and the Order of the Phoenix (film)
One cut Goldenberg had to make, which he "hated" to do, was the absence of Quidditch, the Wizarding sport. "The truth is that any movie made of this book, whoever made it, that had included the Quidditch subplot would have been a lesser film", he said. In the book, Ron grows as a character by trying out for the Quidditch team. "Ron facing challenges and coming into his own in the same way that Harry is, we tried to get that into the film in other ways, as much as possible. So, you feel like, if not the details of that story, at least the spirit of it is present in the film". The change disappointed actor Rupert Grint who had been "quite looking forward to the Quidditch stuff".

In a significant scene in the book, Harry sees a memory of his own father humiliating Snape in their school days, and Snape insulting his mother after she stood up for him. In the film, it is abbreviated to an "idea", in Goldenberg's words. "It's an iconic moment when you realise your parents are normal, flawed 
harry potter and the order of the phoenix movie summary In the fifth year of Harry Minister of Magic Cornelius Fudge has appointed a new Defence Against the Dark Arts professor: Dolores Umbridge. Umbridge immediately clashes with Harry and punishes him for his "lies" about Voldemort by forcing him to write a message with a magic quill, scarring his hand. Despite the concern of his best friends Hermione Granger and Ron Weasley, Harry refuses to report Umbridge's punishment to Dumbledore, who has mysteriously been ignoring Harry since the summer who was handling its visual effects? London-based company Double Negative when was the company founded? UNANSWERABLE
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Harry Potter and the Order of the Phoenix (film) [SEP] Differences from the book
At 766 pages in the British edition and 870 in the American edition, "Order of the Phoenix" is the longest book in the "Harry Potter" series. Screenwriter Michael Goldenberg described his task to cut down the novel as searching for "the best equivalent way to tell the story. My job was to stay true to the spirit of the book, rather than to the letter". Goldenberg said that Rowling told him, the producers, and Yates that "she just wanted to see a great movie, and gave [them] permission to take whatever liberties [they] felt [they] needed to take to translate the book into a movie she would love".