[Class Assembling] Welcome to Filmmaker IQ.com, I'm John Hess
and today we're going to look at the largely forgotten special effect technique of Slitscan
and try to recreate the Stargate Sequence from 2001: A Space Odyssey using Legos. Imagine it's 1966... this director named
Stanley Kubrick comes up to you and says, "I want you to create the Stargate sequence
for my new film, 2001: A Space Odysseey where Dr. David Bowman travels through time and
space before landing in a cosmic zoo and ultimately being reborn as a Star Child. Yeah Buck Rogers this ain't. No film at
that point treated space travel so seriously. Oh Well this shouldn't be too hard... We'll
just pop open After Effects, drop in a couple pieces of artwork, throw on the 3D camera
and animate it flying through this stargate tunnel. Oh wait, it's the mid sixties and the computers
at the time were the size of living rooms and had less computational power than a modern
calculator. Kubrick was making a serious space film and he didn't even have a full picture
of Earth as seen from space - this famous one, the blue marble - the first of it's
kind, was snapped by Apollo 17 Astronauts in 1972 How was this stargate effect created by the
real life 2001 visual effects supervisor Douglas Trumbull? Well to find the roots of this technique
we need to go back to mid 1800s and the origins of slit scan. The Pioneers of photography in the 1800s were
apt to try all sorts of experimental techniques including a technique called slit scan. Slit
scan is the process of putting a sliding slit between the subject and the photographic plane.
The photographic medium under the slit would be exposed as the slit travelled from one
side of the frame to the other. One of the earliest uses was for panorama
photography. Originally developed Joseph Puchberger in Austria of 1843. the Ellipsen Daguerreotype,
was a swinging lens system to capture 150 degree views onto 19-24 inch long plates - keep
in mind this is the era before flexible cellulose film. The following year in 1844, Friedrich
von Martens, a german living in Paris, made the Megaskop camera a similar device using
a swinging lens but controlled by gears and handles. But slitscan really started to gain popularity
when flexible film came into use - especially as a relatively inexpensive way of creating
panoramic shots. By the turn of the century, cameras were developed with that ran the film
along a curved imaging plane. The Slit would then orbit around this curved image plane
creating a panorama. Slitscan had other uses as well - one really
really important use was at the Race track. Gambling on races had become very popular
in the 1940s and avoid the air of corruption in tight finishes, race tracks needed a photograph
of who came in first. Contrary to what movies or cartoons depict, these photo finishes weren't
just some guy with a flash bulb at the finish line and a hair trigger. Instead they used
a variation of the slitscan called Strip photography. Strip photography uses a stationary slit and
the film is moved underneath.. This photo created a record not of spatial relationships
but of temporal relationships - time. The slit doesn't move - only what's in front
of it. So when you look across the photo, you are looking at the exact same spot only
recorded at over a period of time - the slit scan concept and it's digital derivatives
continues to see use today in race tracks around the world.
Slit Scan in Film So how do we get from panoramas and race track
betting to a technique that can be used for motion pictures? Well in 1964 a short film titled "To the
Moon and Beyond" premiered at the World's Fair in New York City. In was shot in Cinerama
360 which was a 70mm single film process using fisheye lenses and projected onto a domed
screen. In attendance was Stanley Kubrick who was getting ready to shoot his grand space
opus. Kubrick hired the special effects company behind "To The Moon and Beyond" to create
some preliminary test shots for the 2001. One of the special effects artist working
at that company, a young Douglas Trumbell, cold called Stanley Kubrick and asked to work
on the film. Kubrick accepted and Trumbell spent 2 and half years working on the special
effects for 2001: A Space Odyssey. For the Stargate Sequence Trumbell was inspired
by the work of Animator John Whitney who also worked on "To the Moon and Beyond". John
Whitney was the animator that worked with Saul Bass on the spiral graphics for Alfred
Hitchcock's 1958 film Vertigo - which happens to be the first film to use a computer for
animation (the computer happened to be a world war 2 artillery targeting computer). During
the 1960s Whitney had been experimenting with leaving a film camera shutter open for long
durations while moving artwork on motorized tables. Trumbell took Whitney's experiments and
combined it with slitscan concept. His approach was to to put the slit outside of the camera.
The camera was placed on a movable platform, aimed at a 4 foot slit - behind the slit were
a wall of gels patterns on a moving table. When the shutter was released and the camera
would dolly in toward the slit while the gels behind the slit were moved from left to right.
After each 60 second exposure, the graphics on the gels would be advanced just slightly
creating the animation of flying through a stargate made of light - a fitting process
which bends the relationship between time and space for a scene where Doctor David Bowman
is doing the same thing. This method of creating slitscan effects would
continue seeing use in special effects for the next 30 years including the Dr. Who intro.
Star Trek the Next Generation would also use slit scan techniques for when the Enterprise
made it jump to warp speed. But once digital effects came into prominence, the painstaking
slow slitscan technique fell by the wayside. Recreating the Stargate with LEGOS After looking Douglas Trumbell's schematic
for his Slitscan device, I decided that making a modern day scaled down model wasn't totally
out of reach - Although I may have underestimated how difficult it would be. Like most mad scientist-slash-filmmakers,
I had a mechanized slider lying around. I built this a couple years ago by adding a
timing belt and pulleys to a slider with the intent of being able to automate the movement. On one end of the slider, I connected the
end pulley to unipole stepper motor which was controlled by a USB controller. Stepper
motors are good for this application because they allow precise reproduction of movement. On the other end of the slider I attached
my LEGO carriage gizmo with a large clamp. Built out of LEGO Technic gears and bricks
which I had since I was a kid, this gizmo draws power from slider's timing belt, sends
it through some bevel gears and a chain where it turns a worm gear. This worm gear slowly
rotates a large gear on which the artwork carriage sits. The artwork itself is transparencies
with various patterns printed on by an inkjet printer. In between the gizmo and the camera I placed
a piece of cardboard a large slit. Using gaffer's tape I was able to get the size of the slit
down to about an eighth of an inch. Creating the raw film for my stargate is really
a matter of creating a timelapse with a long exposure. The stepper motor is controlled
by my laptop where I can tell the motor which step to run to. I designated ZERO as my extreme
close up - I gave myself a little more room so I had some space to ramp up for speed - usually
setting up at step 700 - the numbers are backwards just because of how the system was set up..
From 700 I would engage the motor to head to negative 7000. Watching the motor countdown
on the computer I remotely released the shutter roughly when stepper motor hit Zero. The camera
would then shoot for a 20 second exposure - shooting at F22 and ISO160. The motor travels at 300 steps per second
so the shutter snaps shut right around step negative 6000. The camera would continue to
travel to negative 7000 - a little extra room for deceleration. - now that's one exposure
done. Then it's back to 700 to set up the next
exposure. Once the camera is set to go again, I advance my artwork carriage first by releasing
the power chain on the gizmo and then spinning the worm gear one half turn before reattaching
the powerchain. Then it's the whole process over again for the next exposure. On and on it went. At maximum efficiency I
could do about 50 frames per hour - 20 seconds for the exposure, 20 seconds to reset, 10
seconds to advance the carriage and a little left over for miscellaneous activity. Although the way I describe the process seems
straight forward, actually coming up with the setup was anything but. What works in
theory always finds a thousand complications in application. First off, LEGOs aren't
exactly the most durable building materials - the first 3 of the 5 redesigns for the gizmo
were the result of dropping the it and trying to collect the pieces after they shattered
across the floor. On top of that LEGO gears have some give in
them which isn't great especially when working on a small level that this model is. But Legos
are easy to assemble and experiment with and they were what I had available. Trying to dial in the speed of the carriage
was another difficult thing to accomplish. I tried manually moving the transparency and
moving the carriage itself but It wasn't until the final design which used a worm gear
which I could rotate to fine tune the position did I get results that I found satisfactory. For 2001, Trumbell's slitscan machine pulled
focus throughout the move and did slight pan left or right to fill the frame with the light
streak - both of which I was unable to reproduce. His movement was 15 feet whereas my model
only ran about 3 feet and his slit for his artwork was 4 feet high - mine was not more
than 6 inches. But unlike Trumbell's machine which was
fully automated, I had to babysit mine - making small adjustments for each exposure. Again
and again and again... But to my advantage I have HAL, or rather
After Effects. Using After Effects, I could duplicate and stretched out my image sequence,
and apply nifty color effects to create my very own slitscan stargate. There's nothing quite as humbling as spending
a 12 hour day creating 16 seconds of footage. As much as I have a deep appreciation of how
they did it back then, I have a much deeper appreciation of just what is possible today.
Slitscan has been replaced with digital processes that can accomplish much more and much more
easily. The filmmakers who came before us didn't
have CGI, not because they thought practicals and models or optical effects were better,
but because it just wasn't available to them. But these filmmakers still strove to
make the best stories they could with what they had available. Some succeeded triumphantly
like Stanley Kubrick and Douglas Trumbell with 2001, but many times, as history has
forgotten, some have failed. I don't think the spirit and the need to stories has changed
much... Just the tools that we have available to us. The filmmakers before us created great
works in spite of their technology.... So what's your excuse? Go out there, experiment,
and make something great! I'm John Hess, I'll see you at Filmmaker
IQ.com
Really love this channel. Got lots to offer for movie lovers. This video made me appreciate 2001 and Kubrick on a different level.
Great video, subscribed to channel. Thank you.