Image copyright Getty Images Image caption Spike Lee and Martin Scorsese want the Academy to change its mind

Spike Lee and Martin Scorsese are among more than 40 directors and cinematographers who have signed an open letter criticising the decision to hand out four Oscars during the ad break.

Edited speeches from the winners of best cinematography, editing, hair and makeup and live action short will be played later in the ceremony.

The signatories, who also include Roger Deakins, have urged the Academy to reverse the decision.

What is the issue?

On 11 February the Academy emailed members to say that, in order to keep the show down to three hours, they would be presenting four awards during commercial breaks.

Their winning speeches would then be aired later in the broadcast in edited form.

It is hoped the shorter ceremony will stop falling viewers for the ceremony.

"Viewing patterns for the Academy Awards are changing quickly in our current multi-media world, and our show must also evolve to successfully continue promoting motion pictures to a worldwide audience," the email said.

What has the reaction been?

Russell Crowe called it "a fundamentally stupid decision" and too "dumb for words".

Double Oscar winner Alfonso Cuarón, whose film Roma is nominated for 10 Oscars this year including cinematography was one of the first to object.

Fellow director Guillermo del Toro also voiced his concern.

Gareth Ellis-Unwin, Head of Film and Animation for the skills charity ScreenSkills and the Oscar-winning producer of The King's Speech, told the BBC he would not be voting in the last round of the Oscars as a protest.

"I think it is a damaging move not to recognise some of the roles that are critical to the filmmaking process," he said.

"Cinematography, editing and make-up and hair are vital to the process yet are among the many jobs in the film industry that many people don't know about.

"If we want to continue to recruit new talent into the industry, it is important to showcase all the opportunities available and not just the starry ones. This is particularly important if we are serious about creating a more diverse and inclusive workforce."

Spike Lee whose film BlacKkKlansman is up for six Oscars this year, wrote to the LA Times along with his editor Barry Alexander Brown.

"Without cinematographers and film editors, I would be lost, wandering in the cinema wilderness," he wrote.

Director Edgar Wright is not convinced the move will bring any more viewers.

And Seth Rogen's tweet has been liked more than 80,000 times.

Who has written the letter?

There are more than 40 cinematographers and directors who have criticised the decision.

They include Damien Chazelle, Spike Jonze, Ang Lee, Spike Lee, Seth Rogen, Martin Scorsese, Quentin Tarantino.

Roger Deakins, who finally won an Oscar for cinematography last year after 14 nominations, is also a signatory along with 32 other cinematographers.

There are also 53 filmmakers named including Paul Lambert who won an Oscar for his visual effects work on Blade Runner 2049.

What does it say?

The letter says that by "relegating these essential cinematic crafts to lesser status... is nothing less than an insult to those of us who have devoted our lives and passions to our chosen profession."

They are asking for the decision to be reversed.

"The vocal response from our peers and the immediate backlash from industry leaders over the Academy's decision makes it clear that it's not too late to have this decision reversed," the letter reads.

It adds the Academy was drifting from its mission in celebrating excellence in the cinematic arts.

"Unfortunately, we have drifted from this mission in our pursuit of presenting entertainment rather than in presenting a celebration of our art form and the people behind it," it said.

Image copyright Getty Images

This is not the first controversy over this year's Oscars

The Academy announced plans to introduce a new popular film category but decided to postpone it after a backlash.

Kevin Hart pulled out of hosting the awards following a controversy over homophobic tweets.

The show will now have no host.

What has the Academy response been?

The Academy has responded with a letter to its members reassuring them that no award category "will be presented in a manner that depicts the achievements of its nominees and winners as less than any others."

It clarified the categories were volunteered by their branches to have their nominees and winners announced by presenters, and included later in the broadcast.

The ceremony will be live streamed for the first time this year and these awards can be watched live online.

The letter states that show producers have "given great consideration to both Oscar tradition and our broad global audience.

"We sincerely believe you will be pleased with the show, and look forward to celebrating a great year in movies with all Academy members and with the rest of the world."

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