What actually happens when a director asks you to previs a scene?

The Call of the Wild Previs Momment

Halon breaks down a single previs moment from ‘The Call of the Wild’

I’ve always admired the work of previs artists who often have to take in pieces of script, notes from directors, or just general ideas when conjuring up their animatics.

So, I thought I’d ask Halon partner/supervisor Brad Alexander how he and his team previs’d a single moment in Chris Sanders’ The Call of the Wild. The central dog in the film, as people will be aware, was fully CG, so Halon had the unique opportunity to imagine so many of the scenes from the movie.

The particular scene we’re talking about is the moment the dog, Buck, is pulled along by his collar, dragging up a hallway rug. It’s a simple moment, no doubt, bit still one that was previsualized and had the role of informing the live action shoot, including how the special effects for the rug pull would be carried out on set, and then of course how MPC would animate the final CG dog.

Alexander breaks down that moment below, including how it also evolved into postvis, but first here’s an exclusive look at Halon’s entire previs reel for The Call of the Wild.

Brad Alexander: Chris Sanders has an innate talent for very quickly drawing detailed illustrations, complete with envisioned backgrounds, how he sees the animation blocking out, everything. I would sit with him as he drew out key story frames, so our pattern of work flowed in an extremely interactive and dynamic way.

Sometimes he would do this in formal reviews, sometimes impromptu at an artists desk while doing rounds, or other times simply in passing by. These story beats would come to life as a 2D drawing and his verbal narrative and direction as opposed to traditionally working via a script.

What was most challenging was trying to nail the performance on the first go around. This goes in general for all shots of the film actually, due to the massive volume of work we had ahead of us. This involved asking lots of questions upfront in the creative moment. Below are the evolution steps of this specific shot:

A. Storyboard animatics – Drawn by Chris and edited into a QuickTime with music, so we had a general idea of the timing the shot would last.

B. We then did the first pass of previs in Maya grayscale, which was sent to editorial and edited in along with surrounding shots to make sure it matched the pacing that was requested. Upon review, at this point, we would generally get notes about animation details and timing.

C. We then did a second pass of this shot in Maya greyscale previs to address the animation note that Chris had requested and re-reviewed. At this phase of approval, we would then be given the go-ahead to take it to engine.

D. We would then take our previs into Unreal Engine, which would entail exporting all of the animations, and assets to render and light for further review. It was reviewed and approved until it was time to shoot.

E. At this point, we had given all of our camera data, lens, distant to subject, etc. over to production for shooting in illustration and QuickTime format, so it was easy to replicate on set with numbers to back everything up.

F. When we received the live-action plate back, it was of Bradley Whitford pulling a weighted collar on a stand that included a live-action effect of the weight at the bottom of the stand bunching the carpet up. So we 3D tracked the shot, exported our camera into Unreal, and rendered our performance from the previs we did of Buck so that it aligned with the plate.

G. Upon this point, we had previs’d most of the film, and principal photography was complete. We were given notice at this stage that the color of Buck was going to change from black to brown. This next pass was to address not only the color change to this shot, but also all other shots that we had completed that were in the edit.

H. We were finally given one small performance note before it was signed off and turned over to VFX for finals to be completed.

You can see more of Halon’s previs and postvis reels on their website

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