Part
1 - An overview
by R.A. Stringer csc
APRIL 1996
An amazing number of picture
qualities
As you sit flicking your TV remote control through
the large number of channels available to us nowadays,
you can instantly review an amazing collection
of differing picture qualities. There are old
movies, new movies, game shows, talk shows, drama
series, soap operas, local news, live sports -
and all these programs use different originating
material, new and old post path technologies involving
various generation stages, with many different
people contributing their two cents at every phase
of production. And these images end up by air,
satellite and cable on one of the most limiting
components - your NTSC television receiver.
The originating material has a large part to play
in picture quality. The two fundamental image
capturing systems are film and video. One uses
photographic emulsion to form a real image and
the other converts images to electronic information
which is eventually scanned onto a video screen.
Of course, on television, both formats are presented
through the video medium.
Film
Motion picture film has had a consistent longevity
for over 100 years. At present, film's biggest
asset is large screen projection. All you have
to do is experience an IMAX film on a screen six
stories high to realize the power of film projection.
This is why feature film production and distribution
uses film. Video projection, in spite of significant
improvements, has many obstacles to overcome to
compete with a projected film image. There are
NTSC resolution limitations, and with image format
uncertainty, the high cost factor becomes a problem.
Film maintains a visual prestige with its dominance
of the big screen as well as subsequent movie
videotape sales and rental distribution. A large
portion of television time is taken up by feature
films and many TV programs are shot on film.
At present, with much uncertainty of video standards
to come - HDTV, digital tape, disc storage, home
computer video - film with its photographic image
and standard 16mm and 35mm formats has a much
longer life than video images which are governed
by specific cameras, electronic components and
different recording mediums. If you shoot film,
the image is ready to adapt to any new format,
and you have optional framing available for widescreen.
Future formats will have to cater to film transfer
for a long time to come. When servicing world
wide distribution, film can be transferred to
the different international standards with no
conversion compromise. Film also allows a TV show
to have optional theatrical release and festival
distribution. Stock shot companies certainly prefer
the archival nature of film. Ernest Dick, an archivist
for CBC Ottawa commented in Playback's Video Innovations:
"In the almost 40 years we have had video
amongst us, we have created almost 40 formats
to contend with in our archives. Most of these
formats were specifically designed to be idiosyncratic
without concern for compatibility with competing
or succeeding technologies".
Video
Video as a visual medium is amazing. You can see
the image right there. Playback the tape immediately.
Shoot events live. Indeed, the invention of the
video signal itself allowed televisions to enter
our homes. But the formats within video keep changing,
and since new equipment is comparatively more
expensive, it is very difficult to keep up with
the latest developments. Broadcasting has changed
from black and white to color, from live to tape.
And even over the past few years, we have seen
many changes in videotape formats, from 2"
to 1" to D1 and D2, from 3/4 to VHS, and
from Betacam to SP to digital. Manufacturers complicate
the situation by introducing competing standards.
Panasonic has their own MII system and what about
Sony's Betamax format for home consumers
- it is now virtually extinct from competition
with VHS. Not only does video equipment go out
of date quickly, but it takes a while for new
technology to catch on, especially since it is
usually the most expensive toy in town. Sony's
new digital Betacam is a good example - why buy
a one-piece digital tape camera when most of your
clients are still posting in SP? Even the recent
non-linear edit systems are generally hooked up
to Betacam SP machines. This makes it difficult
to trade in your old camera, that is, if there is
still a demand for the older model. Video cameras
only have a life of three to five years - then
they're considered obsolete ........ just
paperweights!
Cost
The cost of the actual film material is much higher
than videotape. Half hour sitcoms cost $50,000
US more to produce in film. Just to see a 16mm
workprint costs $30 a minute for stock, process,
and print. If you transfer processed 16mm negative
to a corrected master tape it costs approximately
$40 a minute (for 35mm it's more like $100
a min). Tape stock in the popular Betacam SP format
costs $1 a minute, and it's ready - right
out of the camera, but of course, the recorded
images and the tape format are fixed at the present
day standard.
There is another downside to lower cost videotape.
On video productions, people tend to shoot more
than they need. Film has always had a built in
discipline where people have to know what they
want and plan their shots carefully. I think editors
who have been around for a while will agree on
this point.
In general, film cameras are cheaper to rent because
they have a longer life. This is especially true
on a weekly rental where film cameras might be
half the rental cost over the latest video cameras,
although with video you have a choice of lower
end cameras with varying image standards. Camera
purchase prices could be considered equal in the
two formats now, but an older film camera, which
was one third the cost ten years ago is still
competitive, because it is the film stock which
improves with time, not necessarily the camera.
Recent changes in film cameras include user refinements
but the basic principles remain the same. NTSC
video cameras have no international flexibility.
There are almost no PAL video cameras in Canada
and importing one can be very expensive. With
film, set your camera at 25 fps, and the film
can be transferred to PAL (or whatever the producer
requires) without any quality loss.
Unlike video cameras, film cameras can be upgraded
for widescreen formats, time code, video assist,
and they accept prime and specialty lenses. But
there are certain camera products which film cannot
easily duplicate, like the mini video cams that
ride with race cars or capture hockey goals from
inside the net.
Television
Television uses both film and video product on
almost a 50-50 basis. Some sources say film content
is as high as 70% in prime time. Film is used
on the popular evening shows, commercials, music
videos, movies, and some documentaries. Some multi
camera studio shows like Seinfeld use film, but
Home Improvement is shot on video. The John Larroquette
Show and Beakman's World are shot on video
but utilize the Filmlook process, which mimics
some of film's properties (at a cost of $100
a minute). Video cameras are used for sports,
news, and many other information shows and studio
entertainment programs. Film image quality usually
varies with the age of the show, the scanner technology
available at the time and whether or not it was
transferred from print or neg. Video product can
vary a lot depending the quality, cost, and age
of the actual camera and format used.
In 1954, when Ampex introduced videotape, the
Daily Variety headline proclaimed "Film is
Dead". Since then, many people thought video
would have replaced film's presence on television.
But so far, history has proven them wrong.
The Look
Most viewers don't pick up on the differences
of film and video. They are too involved in the
content of the program. But for those of us who
are interested, the difference is fairly significant.
One fundamental difference is the function of
exposure over time. Normal 24 fps film records
an total image in 1/48th of a second, but misses
the information occurring in the next 1/48th as
the shutter is closed to allow for the film to
move on to the next frame. When transferred to
tape the image is broken up in a "3-2 pull
down" process that splits up the image so
that 24 film frames fit into 60 fields or 30 video
frames. Filmlook utilizes this situation with
what they call "frame-rate illusion"
to help create film-like images. You can also
shoot and transfer at 30 fps, then every frame
of film fits a video frame. Video cameras lay
down image information constantly and form a total
scanned image in 1/30th second. There is less
strobing on pans and car wheels don't look like
they're going backwards on video. But with film
cameras you can increase the frames per second
to create a much smoother slo-mo than normal video
cameras and most have built-in time lapse capability.
I asked some friends in Compuserve's Broadcast
Forum for some opinions on the different "looks":
Film - "sits so comfortably to the eye",
"a human look", "subtle colour
quality", "textured and dreamy",
"creates a better atmosphere for imagination
and fantasy", "lush, moody, and rich".
Video - "flatter and less magical",
"here and now reality", "in the
face", "smoother motion", "crisp,
precise, and electronic", "more immediate
and real".
Some say that the "look" can be explained
with a microscope. Film images are made up of
integrated organic film grains with a fibre like
quality. Film granules record information independently
and they contribute to film's high resolution
and photographic tonal range. Video pictures consist
of pixels or scanned dots and are influenced by
the overall picture signal.
Everyone has different opinions on an image's
"look" based on their background and
experience, not to mention a person's feeling
on what imagery best matches the eye's rendition
of the world around us.
Elements of craft
Of course, regardless of the camera system or
all the other variables down the line, these images
have another important criteria - they are created
and manipulated by people known as DOPs, camera
operators, videographers, art directors, and lighting
directors.
I'm one of those camera people who started
my career 28 years ago shooting black and white
news film and have since worked with many different
formats. I moved on to color reversal film, and
started shooting 16mm color negative in 1974,
when product improvements made it more popular
in North America. I started using tube Betacams
in 1985 and have followed all the various improvements
in video and film, including shooting Hi8 video
in some corporate and commercial work. I have
been fascinated by the differences in the various
formats, as well as the reasoning behind producers'
usage and the video suppliers' motivation
behind technology and design.
The experiences of the
past
When I first shot video with a tube Betacam in
a studio, it was obvious there were disadvantages
to using portable tape cameras on high production
value shoots. I found myself spending more time
lighting - dealing with cutting down highlights
and building up shadows - so much so that when
I took my eye away from the B+W viewfinder and
color monitor - I couldn't believe how flat
my lighting had to be! And then - it still looked
like "video". The general conception
was, in a controlled lighting situation, especially
when you have many subject elements or want to
shoot dolly shots, film has a faster "point
and shoot" nature - a latitude that is flexible
and handles a larger range than video, especially
with a wide transfer latitude which offers seamless
timing changes. Now, video fans would say "point
and shoot" is video's forte - but that
might apply only to location shoots using available
light and simple subject matter.
Film advocates have said that film cameras are
more portable, but I believe, especially when
you use wireless transmission for monitoring picture
and recording sound, video cameras, although still
designed like boxes, can be reasonably portable.
One piece of video equipment has a major effect
on shooting procedure. The ever present television
monitor is necessary to evaluate the colour picture.
But this allows a lot more people to have control
over the picture than just the videographer and
can reduce craftsmanship to a routine.
Christopher Clayton in an article for Television
Lighting (UK) had a comment about video usage:
"... sadly (video's) accessibility for
the amateur and the novice means that we witness
more poor quality video than poor quality film.
This allied with the fact that it is the cheaper
option and has undergone a relaxation of quality
control, results in greater respect for film and,
of more concern, a regard for video as the
second rate option." David Stringer, a local
video guru, said: "If film people learn to
stop sticking pantyhose (as a diffusion net) behind
the lens, and TV people learn to light properly,
there could soon be peace in the land."
Things are changing
A lot of people in the industry who were used
to film and preferred its "look", gave
up on video when it came to higher production
value applications, even with the introduction
of CCD cameras.
But, as I mentioned earlier, video keeps changing.
New digital technology, along with improved CCD
resolution, and more access to image control has
created video cameras with a new "look"
- with a quality all their own. The pictures from
these cameras are just starting to appear on television,
and when you see them, even the skeptics might
agree they are bridging the gap between video
and film. Rob Sim of Sim Video believes the Sony
DVW-700 camera could take on a film TV series
and he just recently completed tests with producers
who are interested in the potential of the new
camera. He believes the overall cost saving (estimated
at $13,000 a show) will appeal to producers who
are faced with tighter budgets nowadays. DOP Harry
Makin is quoted in a Sony article: "The look
is transparent. It's silky. Digital creates
its own visual reality and its damn good!".
Another big advantage is that digital tape has
no generation loss through the digital post process
and therefore should be more adaptable to format
changes.
There was a write up in American Cinematographer,
November 95 about a low budget feature film "Dying
Is Easy" by Deborah Dobski. Sony offered
a wide screen DVW-700 to the production as part
of a test program. The feature was edited on Avid
and had an film transfer for release. According
to Dobski, it was a success, but she is shooting
her next feature with a larger budget on 35mm.
I was impressed with a technical paper in SMPTE
Journal (also reviewed in last month's CSC newsletter)
regarding the all digital camcorder ("the
arrival of electronic cinematography") which
claimed the pictures from the 700 were as good
as 35mm - then I noticed it was written by two
Sony vice-presidents. It claimed that the camera
was equal to 35mm in sensitivity, dynamic range,
colorimetry, resolution, and highlight handling.
But, "it does not lay claim, however, to
producing the "film look" which remains
bound up with those secondary imaging characteristics
exclusive to 35mm and 16mm film such as 24 fps,
shuttered capture, and film grain". The article
goes on to suggest these are fundamentally undesirable
qualities with grain structure akin to video gain
"noise" and that 24 fps images are "technically
subsampled temporarily".
Another interesting development is the introduction
of digital cameras designed for home use which
are also producing very impressive images. The
new DVC cameras are being scooped up by corporate
producers who feel the pictures are as good as
analog Betacam technology which has a solid hold
on the market now, but is 10 times the cost of
the most expensive digital handycam!
The Future
New products are being introduced all the time.
This article will probably be out of date soon
after this magazine is printed! Already there
are new camera models I haven't even seen
yet. The future holds many changes - computer
imagery with internet transmission and direct
delivery of programs by satellite or hybrid fiber
coax might totally override NTSC limitations which
was originally designed for black and white antenna
reception. Already non-linear editing and Cineon
style computer effects have made storage of video
on disc a reality, so much so that Avid and Ikegami
have developed a disc drive back for cameras.
The potential of connecting CCD or other image
capturing devices direct to digital data will
create flexibility in future video systems, perhaps
reducing tape's use to only a back up. TV
scanning will probably be replaced with grid point
systems using liquid crystal light valve technology
with flat screens "wired" for picture
information . This is an exciting time of change
right now - but perhaps things are moving too
fast for us to keep up.
In summary
Certainly, controversy over film and video will
be with us for a long time and the introduction
of digital video product is going to mean stiffer
competition between the suppliers. When you consider
the many pros and cons, there is a lot more to
it than "the look". A lot of the articles
I've read go to neutral corners by saying
film has its special application as does video.
It is not an issue of which is better but more
the function of how each suits the particular
production, story and budget. Sounds good to me!
Part 2 - Camera comparison
test
by R.A. Stringer csc
MAY 1996
Seven Systems - A Comparison
With all the latest developments in digital video
products, I thought it was a good time to try
some new and existing video formats with film
- side by side. A lot of the opinions and comparisons
of film and video in part one of this article
come from the experiences of the past, and I felt
it was time to re-visit this domain and see at
what digital video had to offer.
I tested seven systems: 35mm Kodak 5293 stock
using an Arriflex 2C, 16mm 7293 stock using my
16mm Aaton XTR, Sony 537A with PVV-1A recorder
and SP tape stock, Sony 570is with BVV-5 and SP
tape stock (similar to 400A), Sony DVW-700 digital
camera with digital tape stock, a Sony 3CCD Hi8
camcorder with Fuji E6120 tape, the new Sony DCR-VX
1000 digital handycam with Panasonic 6mm DVM60
tape. I shot a color chart, a newspaper page,
some portrait studio lighting setups with demanding
lighting elements (bright window, table lamp,
neon sign, and dark shadow detail), candle lit
face, natural window light, night exterior, and
various day exteriors.
I realize there are many competent manufacturers
of professional video cameras whose product is
just as good as Sony's - but I used the Sonys
based on the popularity of their portable cameras
in this region. In Canada, Sony has a solid hold
over this product than in other countries. In
the States, companies like Ikegami and Panasonic
participate in a more competitive market. As it
was, this test became a large undertaking and
I had a full day of shooting with this many cameras.
By the way, the 35mm Arri 2C is probably 20 years
old and worth $7,000. The DVW-700 package costs
at least $100,000.
General observations
The first thing I learned from this shoot was
about comparison testing itself. In side by side
cutting of the same subject matter, you pick up
on things you don't notice when screening
just one item. The most obvious example was the
motion breakdown component of film. When screening
the shots on film alone, the motion seems natural
and normal. But, cut next to video, the film movement
becomes exaggerated - a slight strobe like quality
similar to multiple printing (two or more frames
re-printed). Perhaps this illustrates a facet
of the different "looks". In film, movement
is integrated into the picture, rather than video,
where motion is crisply defined.
Also the issue of proper exposure is critical.
A shot might seem fine on its own, but compared
with others of the same subject, overall variances
are more noticeable and affect comparisons. In
some situations, I bracketed exposures and picked
the best combination.
Another problem, especially with the new digital
tape product from the Sony 700 and the DCR-1000
6mm, was image deterioration though the editing
stages. After going through a few analog stages
and a non-linear edit, the VHS copy of the DCR-1000
didn't look at all like the original - much
worse than normal generation loss. The pictures
lost their snap and the blacks were just mush.
The pictures from the 700 also lost their high
grade look. This means these new images are not
practical unless kept in their digital domain.
It also underlines the problem of format change
- right now it isn't as easy to access digital
post gear especially at a competitive cost. Even
the digital tape itself is double SP tape costs.
For my final edit, I chose a digital tape to tape
on line to keep image quality equal and consistent.
Another factor in the new digital formats is a
problem which I discussed in part one of this
article - video format incompatibility. Manufacturers
are already shooting themselves in the foot with
Panasonic and Sony introducing two different digital
format standards.
One thing I noticed in post was the flexibility
when scanning film to tape. There was a large
range to choose from the photographic film emulsion.
Video images are less flexible to alteration once
they're shot and any adjustments made in
camera are permanently built in to the image.
Ian Brown at Medallion PFA says with Rank scanners
you could actually correct for 3 stops overall
underexposure and 1 stop over (with some compromises
of course) which is not yet possible on tape.
But with tape, so long as you are monitoring the
picture when shooting, such exposure variation
shouldn't happen, right? Colorist Brian Lovery
told me digital videotape now has more latitude
in post than analog but there are still obvious
limitations compared with film.
Results
Looking at the colour chart shots, the Betacams
were apparently more sensitive than the 200 ASA
film. The 537A was better by a half stop, the
570 a bit more, and the 700 perhaps a full stop.
The 700 worked best closed down as much as half
a stop after eliminating 98 unit zebras from whites.
The Hi8 and Digital DCR-VX 1000 seemed pretty
close to the film rating, with the DCR less sensitive
in some situations at zero db. But sensitivity
depends a lot on subject matter because video
adjusts to reflective values. In one situation
where the subject was in front of a bright window,
only film maintained shadow detail in her face.
The hot window influenced the rest of the video
picture, creating a silhouette effect (this is
not to be confused with auto iris effect - the
cameras were all set manually). And even though
the film's rating seemed lower than the Betacams
on a brightly lit colour chart, in a dark hallway
or in candlelight, the transferred film image
kept pace with the video cameras.
The lower priced Betacam 537A compared very well
to the higher end products. In one instance it
rendered more detail in an overexposed window
than the other video cameras, including the 700,
even though they all had the same wide open aperture.
The 537A looked very close to the more expensive,
but older 570is, if not better on some shots.
The results from the $6,000 DCR-VX 1000 were impressive,
especially when screening the original tape. The
images had a softer quality and I think the camera
deserves the "look all its own" description
more than its digital big brother. The DCR images
delivered good bright color rendition and sharpness
and latitude was right up there with the expensive
cameras. But in low level lighting situations,
the camera didn't have the sensitivity we
expect from video nowadays, and relied more on
noisy video gain to boost exposure. The DCR-VX
1000's viewfinder (color LCD) is a nice idea,
but is difficult to work with, both in focusing
and setting manual exposure because the contrast
of the image varies with the angle of view and
it is not as sharp as standard viewfinders. And
the manual overrides and extra gimmicks are annoying
as they are on any of these small cameras. The
DCR produced smear with a candle flame but wasn't
as noticeable on night headlights as the Hi8.
The 700 certainly gives a very crisp image and
a very pleasing picture, but still has video imaging
characteristics. The camera delivered good shadow
detail in the studio setups and looked very good
in the exterior shots. Internal setting adjustments,
one of the main advantages of digital cameras,
can be stored on a small setup card. This is a
much better way of creating a softer looking picture
than shooting with diffusion filters. Newspaper
typeface was very sharp on the 700. In comparative
cutting with 16mm, especially viewing on high
end equipment, the 700 has a very clean look.
The film images were precise and accurate, predictably
consistent within the realm of the film "look".
Film had good latitude in all situations, especially
in highlight detail, which has been always been
an advantage of film over video. When video was
fighting a bright window in the shot, film not
only maintained the shadow detail, but managed
to hold exterior detail better than video. Most
of the time grain added texture and tone to the
16mm image. Although, with certain subjects, especially
on exteriors, it was more noticeable beside the
clear image of the 700. I could have shot a finer
grain emulsion outside, but then the camera sensitivity
comparison would have been off balance. Grain
was not a problem with 35mm, which in general,
delivered high quality images with good crisp
detail, while still maintaining a soft tonal look.
35mm's minimum depth of field creates a distinctive
look as sharp foreground subjects stand out from
the softer backgrounds.
In summery
From observations of my test footage and others,
I feel the DVW-700 still has video characteristics
and a video look, but a very good video look -
sharp and clean. It looks best when kept within
the digital process and viewed on a good monitor.
And this can be a severe limitation in the present
analog world with VHS distribution systems and
not much improvement in present day consumer TVs.
But I still think film, especially 35mm, which
holds up well on any video system, will maintain
a solid position on prime time TV. An article
in ASC magazine (Jan 96) quotes Larry Thorpe of
Sony: "We don't think that digital origination
for television will take a big bite out of film
origination. We believe the total pie is just
going to grow and grow based on the stimulus of
all the new digital distribution media of the
future".
The Sony digital 6mm format has great potential
but inherent limitations like built in compression
make it difficult to edit and copy, especially
now, as auxiliary gear, including interface connectors
which feed right into computers, are not yet available.
Panasonic is ahead of Sony in this regard, with
their present mini-digital system which allows
the small tapes to played on a DVCPRO VTR with
a cassette adapter.
I would like to thank the various suppliers who
contributed to the comparison test: Kodak, Sim
Video, Medallion PFA, Post Port, Production Services,
Cinequip, Doug Wright, Tom Fletcher, Ron Chapman,
Vlad Czyzewski., Freway Productions, and Sherrida
Personal Management for providing Teri Landry.
Teri was great and hung in there through 40 shots.
Thanks to Lance Carlson and Suzan Poyraz who helped
on the set.
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