by Alan Stewart
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Alan Stewart |
The subject is shooting video for film release, so I will
begin by saying a little about why one would consider such
an option. Only in the most rare situation would one shoot
video and convert it to film for aesthetic reasons, so we'll
start with the principal reason an independent filmmaker would
shoot video... money.
Your goal is to produce entertainment in a medium that traditionally
requires a lot of cash. In movie making, maybe more than in
other industry, money talks. Money buys time, and creative
options, or creative freedom. Obviously, money buys crew,
locations, materials, actors, etc. If you have little money,
you will have to make good use of the resources you do have,
or that you can afford on a skimpy budget. So what do you
REALLY need money for?
If you can write a good script, that won't cost you much.
Maybe you know some talented actors who will perform in your
film for no money, or very little. There seems to be no shortage
of hairdressers, lighting technicians, camera operators and
so on, who will donate some of their time to a worthy project.
What really matters when making a film is what ends up in
front of the camera, so let's assume you have directorial
talent, a good script and can scrape together an adequate
cast and crew. The rest is technical, or 'behind the camera'.
Areas that have always been difficult to negotiate around
are camera equipment, film stock and lab costs. I once made
a film for 'nothing' and it still cost me $35,000. I owned
my own equipment and didn't pay the cast or crew, but the
costs of film stock, laboratory, negative conforming, sound
mixing and delivery items (film and video elements required
by the distributor) added up to quite a bit. I did spend some
money on transportation and food, but even if I'd shot it
all in one location and let the crew starve (not recommended),
I'd still have spent over $30,000. So we come to one means
of circumventing some of those 'fixed' costs... shooting video.
Shooting video for a film release can be inexpensive on the
front end, but is not cheap on the back end. As a native Texan
it comes naturally to me to compare filmmaking to drilling
for oil: first you get the money to drill the hole to see
if there's anything there. If you find oil, you won't have
any trouble getting the money to pump it out. So how does
this apply to filmmaking? If you don't get it right off, you
might want to consider some other line of work, but I'll explain
briefly in case you still plan to hang in there. The 'oil'
you are looking to find is the entertainment value in your
film. You have to get your film in a form that will demonstrate
it's entertainment potential, or in the distributors eyes,
the market value. Since you can shoot hours of video at a
fraction of the cost of shooting film, and as it is becoming
easier/cheaper to edit video and mix sound with computers,
you can put together a fairly sophisticated 90-minute film
for a few hundred dollars.
Once you have the show in a presentable form on video, you
can shop it around and soon find out if you are actually talented,
or if your friends and relatives have been lying all along.
Seriously, if your movie entertains and has market value,
then you are on your way. The costs of transferring video
to film and delivering the show to the market place will be
covered, if you can make someone a million dollars, or at
least make them think you can. "In The Company of Men"
is a great example of guerrilla filmmaking... good script,
good cast, few locations, no frills, technically weak - shot
on 16mm, doesn't look great or sound great. But who cares?
It cost something like $25,000 to put together and I saw it
twice! "Rhinestone" cost millions to make and I
couldn't sit through it once. Recent video-to-film successes
are "The Celebration" and "Vietnam: Long Time
Coming". These films entertain an audience and achieve
their goals nicely, and, had the filmmakers insisted on shooting
film rather than video, the films might never have been made
at all.
Before I get into some of the technical considerations, I'll
say a last word about aesthetics. Look at works that have
been shot and/or finished on video and then transferred to
film to get a sense of the 'look and feel'. If you are planning
to make the next "Out of Africa" or "2001:
A Space Odyssey", you may want to start raising the money
to shoot film. Be sure the medium suits your material, or
the other way around. Things may change in the future, but
today video does not look like film. Whether you spend $40,000
or $300,000 on your video to film conversion, you will still
not produce a visually beautiful film. But if you can tell
a story and entertain people without the glorious images,
video-to-film gives you an opportunity to do that at a reduced
cost and potentially put yourself in a position to make another
film anyway you want.
Terminology and Pratices:
When you enter into this arena you will need an understanding
of the terms and practices used film production, video production
and in the computer industry. I cannot bring the novice up to
speed here, so you will want to do research and anything else
possible to get yourself in a position to make the best decisions.
Resolution:
Lets look briefly at the differences between single video
and film frames, or images. Video images are comprised of
pixels - little dots that represent the color and luminance
values of the image. The more pixels per image, or frame,
the greater the detail. The visible area of a frame of NTSC
video has some 307,200 pixels, and a PAL frame yields about
368,640 pixels. Film images are etched right onto the film
emulsion by light and, while there is film grain, there are
not pixels as such. While we see a granular pattern when viewing
film, we do not necessarily see the individual silver particles
that hold the image. These particles range from about 0.003mm
down to about a tenth that size.
An image of 5000 x 3760 pixels is required to truly mirror
the discernible quality of a 35mm film frame. When film frames
are stored as a computer image file there are three common
pixel dimensions used - 2K, 3K or 4K. A 2K image has 2000
pixels side-to-side, a 3K image has 3000 pixels side-to-side,
and so on. The pixel dimensions in height vary depending on
the aspect ratio. Working with 3K or 4K is desirable because
the threshold of human vision is about 2500 x 2500 pixels
when viewing an average movie theater screen (if the picture
were square). 2K resolution is becoming more common because
of the reduced file size and throughput requirements (data
flow) - commerce winning out over art again.
Shoot:
Obviously, you would want to shoot the highest quality video
possible. If you can afford to rent a High Definition package
you could probably also afford to shoot film. Luckily, the
quality of the mini DV cameras is excellent and at $2,500
to $5000 for a good one, they are affordable. The DV format
is 5:1 compressed, but still looks pretty good. When shooting
your video work with lighting ratios around 3:1. Be sure to
watch focus and exposure carefully and do not use any autofocus
or autoexposure features. In those regards, shoot much like
you would shoot film. Don't let you blacks get crushed and
try not to clip the video levels.
Edit:
It is not necessary to edit in the native DV format, but
if you choose to do so, some editing systems use a Firewire
I/O to 'dump' the data from the tape directly to disk. When
working with your raw footage (dailies) at 5:1 compression
you'll need about 13 gigabytes per hour of source footage.
It might be a good idea to work with a system that allows
you to further compress the video so you don't need a room
full of hard drives. There are many possible workflows to
choose from. Avid's products allow you to work at a high level
of compression and then recapture the material at little or
no compression for final output. Avid's AVR77 compression
(2:1) yields a good picture direct off disk. Avid also has
systems that work at D1 uncompressed video resolution (Symphony
and DS). Another possibility would be to 'off-line' on an
inexpensive system that would generate and EDL for a video
on-line from the original tapes, or on one of Avid's high
end systems.
Conversion:
When NTSC video is converted to film, about 307,200 pixels
must be copied to a frame with a potential of holding something
like 19,000,000 pixels, but a 2K frame would be only 3,000,000
pixels (at 1.33:1). Obviously taking any picture and trying
to increase its resolution is a tricky proposition, but in
the case of video-to-film one has to deal with the fact that
a video frame is actually two interlaced fields (the odd lines
are drawn first and then the even lines), and that there are
30 frames per second (30 frames equals 60 fields), and furthermore
NTSC video does not actually run at 30 frames per second,
frames are displayed at a rate of 29.97 frames per second.
While film runs at 24 frames per second with no 'interlacing'.
In video terms, film frames are best compared to progressive
scan (like your computer monitor). I am not going to go into
much detail here explaining the interlacing of video frames
and the frame rate issue. Refer to my website at http://www.zerocut.com
for more on this issues and other principles of digital nonlinear
post production.
PAL video offers some advantages over NTSC in that there
is more video resolution (368,640 pixels), it runs at 25 frames
per second, and the cameras are often cheaper in the USA due
to lower demand. Because the frame rate is so close to that
of film, PAL video can actually be transferred to film frame-for-frame
(it simply plays back 1 FPS slower in the theater). This eliminates
the need for frame 'averaging' that goes on when converting
NTSC 30 to 24, thus reducing motion artifacts.
There are several methods of converting video to film ranging
from filming the show off a video monitor [ :-) ] to scanning
every frame into a high-end computer system which then will
blend the frames and up-res the frames to 3K using sophisticated
filters. The latter method is the best and costs about $2.00
per frame. Do the math and weep.
There are essentially three different video-to-film transfer
devices: Film Recorders, Kinescopes and Electron Beam Recorders.
Each has their positive and negative aspects, including quality
and (most noticeably) costs. The facility will give you back
(depending on the facility) either a film negative or a print
(with or without sound), or a combination of these. You need
to work closely with the facility you select to fully understand
their process, what they need from you and what you will get
from them.
The Film Recorder:
Film Recorders that reproduce the highest quality electronic
image on film, typically from digital files that were filmed
live or created on computers. They boast vertical resolutions
of 2000 or 4000 video lines (called 2K and 4K, respectively.)
There are two basic technologies: 1) Film Cameras that shoot
hi-res monochrome CRT (high quality video screens) through
red, green and blue filters, and 2) red, green and blue micro-lasers
that scan an image on the film's surface without the use of
lenses.
CRT-based systems are made by Management Graphics (Solitaire)
and Celco. These devices are slow, 15-40 seconds-per-frame
for a 4K output image, and cost several dollars per frame.
Laser systems are made by Eastman Kodak (Cineon Lightning).
Digital Cinema Systems (Lux) and Pthalo Systems (Verite).
Laser systems are faster and brighter that CRT systems, but
at a slightly higher cost starting at several dollars per
frame.
To get your video transferred, you will need to send your
videotape to the facility. It is best to master to the highest
quality video you can afford (i.e., D-1 or DigiBeta). They
digitize the tape on their computer, then feed the images
a frame at a time into the film-recording machine. The film
recorder will then film-capture each frame to a film negative.
The Kinescope:
Another method uses a kinescope, which is a very sharp monochrome
video monitor photographed by a specially designed film camera.
The kinescopes drop selected fields to produce a 24 frame-per-second
film (actually 23.976 frames per second) and eliminating the
visible roll bars that occur when filming TV screens.
Electron Beam Recorders:
The electron beam recording (EBR) systems fire electrons
directly onto unexposed film, which is held in a vacuum. The
film is black & white because electrons don't have color,
only intensity. Three exposures must be made for each frame
of color, one for the red, green and blue components of the
image. These three separate exposures are re-printed through
red, green and blue filters on an optical produce a color
negative.
There are very few facilities that use EBRs. Most of the
machines are now owned and operated by Four Media Company
(4MC) in Burbank. 4MC's EBRs transform 16mm only. Both 16mm
color negatives or 35mm color negatives are made on an optical
printer, the latter via a 16mm-to-35mm blow up.
The other major player that uses EBR technology is the Sony
Pictures High Definition Center. The facility opened in Culver
City back in 1991 to create new methods of video-to-film transfers.
They have a unique system based on non-real time, pin-registered
35mm EBR to transfer 1125-vertical line resolution HDTV images.
Sony's EBR outputs three black-and-white separations per second,
which equals one color film frame. Their color correction
and switchers are all HDTV compliant. NTSC video resolution
images are up-converted to 1125-line HDTV, the line-doubled
again to approximated 2K output. The costs are high, around
$7 per second of video, print only. For a 16mm output, they
reduce the 35mm negative on an optical printer.
The LOOK:
The only way to truly know is to test it.
Due to the variables in equipment, lighting conditions and
the specific equipment used, it is impossible to predict what
will be created from a video-to-film transfer. Tests are crucial
to find out what works best for you
Parting Notes:
- Get the framing right for your target release medium.
Are you going to 1.66, 1.78, 1.85, or what? You need to
know before you shoot.
- Know that pans and other camera moves may look odd when
converted to film.
- Visual effects that look smooth on a video monitor at
29.97 FPS may not work to your liking at 24 fps.
- Pay careful attention to the audio specifications. It
is probably best to record the audio apart from the video
with a DAT recorder and then sync it up in post production.
- Be sure you know how much the services will cost and what
you are paying for. Some facilities will not give you the
negative for the quoted price, only one print.
List
of Tape to Film Facilities
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