High-flying VFX on AVENGERS

When visual effects maven Jake Morrison learned that director Joss Whedon would be taking on THE AVENGERS, he knew the highly anticipated summer flick would be in good hands.  "I'm a big fan of Joss Whedon, going back to BUFFY THE VAMPIRE SLAYER; he's an excellent director so I was excited to be working with him," says Morrison.


Oscar-nominated cinematographer Seamus McGarvey, ASC, BSC, used the ARRI ALEXA digital camera system to shoot Marvel's THE AVENGERS, directed by Joss Whedon. McGarvey was impressed by ALEXA's low light performance and suitability for blue and greenscreen work.

Collaborating closely with AVENGERS' main visual effects supervisor Janek Sirrs, Morrison was tasked as a Visual Effects Supervisor for Marvel to manage the second unit in addition to shooting aerial photography and background plates. It was an opportunity for Morrison to help create the ambitious world of the celebrated Marvel comic book series. It was also his first chance to work with the ALEXA camera system. The VFX expert, whose credits include IRON MAN 2, THOR and 300, notes, "The ALEXA is the first digital camera that has a film-like response. To me, it's a big difference from the other cameras I have worked with."

One of the many logistical challenges on the production involved dealing with the multitude of main characters. Each actor had specific needs in regards to blue or greenscreen. "Black Widow has red hair, Thor is blonde, Captain America's costume is not far from chroma blue - there were a variety of different requirements," says Morrison. "We worked out for every scene whether it would be green or bluescreen and took the lesser of two evils as to what we would shoot with."

Keying the ALEXA ARRIRAW footage afforded certain advantages. "The response particularly to green and blue by ALEXA was very good," Morrison points out. "There are a lot of benefits to digital. You haven't got gate weave or grain structure; it allows you to get more fine detail from hair, edges and better extraction of motion blur."

I'd rather have better pixels than more pixels.

For scenes taking place in Manhattan, Morrison's team shot aerial footage over three full days for use as background plates. "My focus is to get as much aerial work in as possible for the audience to see the big expanses, the wide establishing shots, while also making sure that the effects work doesn't look too computer generated," he says. "We're getting much better at making entirely computer-generated environments, but there is no substitute for starting with a real image and adding what you need."


ALEXA's image quality during these shoots was most notable to Morrison after sundown. "The night footage is where I became really impressed with the ALEXA," says the VFX supervisor, who is currently prepping THOR 2. "I'm very familiar with film stocks and you know what you can get away with at night, but ALEXA loves the night. With a good DIT set up, you can get a very rich digital 'negative' with lots of information to work with in post, but still have dailies that look really good - sharp, contrasty and punchy."

ALEXA's 3.5K sensor allows high sensitivity and a wide exposure index to produce its signature look. As technology advances with higher resolutions becoming available, Morrison recommends assessing overall camera performance. "I'd rather have better pixels than more pixels," he says. "Some cameras boast more pixels than ALEXA, but given the choice of that or having latitude and better image sampling, I'd much rather have the latitude. A more grain-less structure with a sharper, cleaner image is far more important to me rather than just having more 'dots'."

 -- An Tran