THE SMURFS 2: Laurens Ehrmann – VFX Supervisor – Plug

In 2011, Laurens Ehrmann explained to us the work of Plug on X-MEN FIRST CLASS. He then supervised the effects of films such as LIVIDE, LES VACANCES DE DUCOBU or PARIS A TOUT PRIX. He also worked as on-set VFX supervisor for the Paris filming of NOW YOU SEE ME.

How did PLUG get involved on this show?
End of 2011, we were approached by Maricel Pagulayan. She was the VFX Producer on THE SMURFS 2, the sequel that will be set in modern day Paris. Maricel and Rich Hoover, VFX Supervisor planned to do a recce in Paris early 2012.
Sony Imageworks was the primary Smurf Vendor but this Parisian trip were also an opportunity to meet additional vendors to work in a shared shot capacity. This first meeting has allowed us to present our approach for building and asset reconstruction. In that case, using a LIDAR scan was not convenient.
We have years of experience in productions involving photogrammetry and we thought it was the appropriate technique. Photogrammetry suits really well building reconstruction and it is a technique fully mastered at PLUG, it was an obvious choice.

A month later, Maricel and Rich proposed us a working partnership, first helping on set, on the other hand by offering us the reconstruction of a famous Parisian sight, the cathedral of Notre Dame.
As a proven test, Rich proposed us to quickly recreate a small part of Notre Dame Cathedral. It seems the test was convincing.

How was the collaboration with Production VFX Supervisor Richard Hoover?
Working with Rich was great. He provided a great brief for the work and was also very receptive to solid new ideas.
On set, I helped them as a tile unit supervisor or for complex shots filmed with multiple cameras. We also support the crew providing on-set data wranglers.

What was your feeling working on an American show taking place in Paris?
No special feeling. Just the pleasure to be part of a new exciting project.

What have you done on this show?
We have mainly worked on the Smurfs ride into Notre Dame Cathedral. We have also worked on some green screen comp.

Can you explain in detail about the creation of Notre Dame and its shot?
For the Notre Dame Cathedral reconstruction, we have used photogrammetry technique.
Photogrammetry is the practice of determining objects from photographic images. Thanks to years of experience in productions involving this technique we have build a rock solid pipeline dedicated to assets or backgrounds reconstruction. Even starting with photos taken pretty far from the subject, we can create detailed an accurate photorealistic assets.

First, our team covered sets with stills along with main photography. For Notre Dame, we shot almost 2000 stills. Some far to get a general overview, some close to get perfect textures.
Then, we have calibrated few cameras to rebuild a lighter model of Notre Dame. This rough model perfectly lined up was sent to Sony, who made the camera animation. Once with knew the camera path, we have started to select and calibrate appropriate stills and then modeled details of this fantastic and complex architecture.
Finally using camera projection techniques, we have textured the model.

Once the Notre Dame and its surroundings were modeled and textured, we have done the comp and delivered the background plate to Sony Imageworks.

How did you work with Sony Imageworks teams for the assets sharing?
As the pipeline of PLUG is based on sharing assets and resources, we were well prepared to pack up a shot or model and send it to SONY. Their specs were really precise and it was a real pleasure to collaborate with their teams.

Can you tell us more about your work on the green screen comp?
Nothing special. As green screen were pretty well lighted, it was not a big deal to make the comp.

Can you describe one of your typical day on-set and then during the post?
Working on set and during post are very different, and I love them both for different reasons.
While shooting, you make sure the shots are setup according to what you need for a successful execution or, in that case, you bring support to the main vfx unit. Being on set is always a great experience. You are in the middle of this whirlwind of excitement.

In post, I work back at PLUG reviewing and ensuring the work is up to the quality standards we strive to achieve. And of course, I would do cineSync reviews with Rich, showing him our progress on the work and exchanging ideas.

What was the biggest challenge on this project and how did you achieve it?
Definitely, the Notre Dame reconstruction. Thanks to our team, it was not a nightmare.

Was there a shot or a sequence that prevented you from sleep ?
Not really, sleep was very well deserved every single night.

What do you keep from this experience?
It was really exciting to be able to work on a project of this size. This allowed us to strengthen the key points and to improve the weakest ones.
Even if we are experienced in photogrammetry, this project gave us the opportunity to challenge us on such a complex architecture. To achieve it, we developed a lot of custom solutions that we have integrated to our pipeline. This will be very useful for us on future projects. We have only scratched the surface of what we can accomplish. That said, most important thing is relationships. We had great time and it was a real pleasure to work with Maricel, Rich and the whole team at Sony.
I am really looking forward to our next project with them.

How long have you worked on this film?
7 months overall with 4 month of shot production.

What was the size of your team?
We were 4 artists working on this show.

What is your next project?
We are currently working on 2 french feature films and are in the loop for some others.
PLUG want to be as busy as possible. We enjoy being involved in many different types of work and use what we learned from different projects to bring efficiencies into our pipeline. We are really eager to be involved in new exciting projects.

A big thanks for your time.

// THE SMURFS 2 – PLUG EFFECTS

// WANT TO KNOW MORE?

– Plug Effects: Dedicated page about THE SMURFS 2 on PLug Effects website.

© Vincent Frei – The Art of VFX – 2013