American Cinematographer - August 2019 - 60

Shooting in the Ether

60

The philosophy behind The Lion
King's virtual methodology was
that it would allow a live-action
director of photography to
employ traditional filmmaking
techniques with a virtual camera,
virtual lenses and virtual lights -
thus meticulously emulating realworld cinematography inside a
computer. The design of the
virtual-production workflow and
toolset was led by visual-effects
supervisor Robert Legato, ASC. As
virtual-production supervisor Ben
Grossmann, at virtual-reality
production company Magnopus, notes,
"The Magnopus team and I worked under
[Legato], and we provided the software,
the hardware, the design and construction of the stage, and the operations."
Inside their production-volume
space at a warehouse in Playa Vista, Calif.,
the filmmakers plotted specific shots, relying on detailed animated 360-degree
"master shots" - created by MPC under
the guidance of Adam Valdez, visualeffects supervisor at the company - and
processed into the virtual world via a
custom-developed suite of software that
employed the Unity graphics rendering
system. There, the filmmakers were able
to join forces, videogame-style, using an
off-the-shelf HTC Vive virtual-reality
system, tracked using Valve's Lighthouse
VR tracking software. For high-precision
tracking, the filmmakers used US Digital
encoders, which, Grossmann attests, gave
them "insanely accurate data [derived
from on-set] hardware systems like a
crane, dolly, fluid head, alpha wheels and
focus wheel.
"Once all the equipment was set
up, we had the entire camera and grip
package attached to a modified drone
controller with a joystick and a lot of
knobs," Grossmann describes. "This
allowed Caleb to pick the entire camera
package up together, and move it around
on the set if he needed to make an adjustment. It also allowed him to control the
zoom and other standard camera
controls. An attached touchscreen let him
change the gears on the wheels, the
speed of performances, and let him drop
August 2019

camera marks so that he could go back to
them whenever he pressed a button. It
also allowed people in VR to see where he
wanted the camera to go when they were
operating - instead of having a taped red
'x' on the floor as a mark, a grip could be
in VR moving the virtual camera towards
a ghosted copy of the camera that Caleb
had placed, so they could hit their marks."
The production also employed
NaturalPoint's OptiTrack sensor system,
which allowed the filmmakers to record
even the slightest nuance of the professional operators' movements with their
non-encoded equipment. "Essentially,
the next generation of motion capture is
an advancement from reflective balls to
an LED emissive camera system,"
Grossmann explains. "By incorporating
over 60 integrated cameras - a combination of OptiTrack Slim 13 and Prime 17W
units - in the ceiling truss, we vastly
increased the size of the volume in which
we could operate. Combined with the
ability to dynamically scale the volume to
fit the [virtual world] in which we were
operating, drones, Steadicam, and largescale handheld shots became possible."
According to Grossman, the virtual
camera was modeled after the largeformat Arri Alexa 65 camera system that
Deschanel and his colleagues took to
Kenya to record reference elements. Pixel
ratio and sensor size for their virtual
camera "was cropped-in slightly from the
full [Alexa 65] sensor to standardize the
video-delivery spec between reference,
capture, editorial, delivery from VFX, and
eventually projection," Grossmann adds.
ASC 100th Anniversary

He further notes that the filmmakers modeled all their lens
calculations after Panavision 70
Series cinema lenses, which had
been supplied to the production
for the Africa reference trip -
including 70 Series 28-80mm
(T3), 70-185mm (T3.5) and 200400mm (T4.5) zooms, and 14mm
and 24mm primes. "We calculated both vertical and horizontal
field of view based on the exact
sensor size of the [real] camera,
using data captured from lensprofiling sessions with actual
lenses," Grossmann explains. "Using that
data plotted on a line graph, we were
able to create a formula that could calculate the exact field of view for focal
lengths that don't exist.
"We even modeled the camera
and lenses in 3D so that when you were
in VR, you could see the exact camera as
it would be in real life, with the correct
lens on it. We did this so that an operator
in VR could look over at a camera and see
what lens was being used."
Virtual-production producer A.J.
Sciutto of Magnopus adds, "The virtual
representation of the light was modeled
after true Arri cinema lights, complete
with barn doors and a lighting stand. The
values of those lights [could] be adjusted
in real time; by changing the color
temperature, we could mimic the light
coming from different sources, and we
were able to adjust intensity on those
lights with a range of 150 watts to 20,000
watts. [The light's spread could also be
widened with the virtual barn doors] to
flood the scene, or narrowed when
focusing the beam to a spotlight."
The filmmakers emphasize that
the ultimate significance of this methodology was that it made it possible for
Deschanel and his collaborators to design
and execute the camerawork in a familiar
way. "This meant they were drawing on
decades of experience and instinct,"
Grossman attests, "rather than standing
over someone's shoulder at a computer
and looking at the movie from the
outside."
- Michael Goldman
American Cinematographer - August 2019

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