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Updated: 2002

New Insights in an Ongoing Debate:

Film vs. Videotape 

Which is better: film or videotape?"

First, we need to acknowledge the fact that this is a controversial subject, especially in Southern California, the "film capital of the world." (If you want to quickly get thrown out of a Hollywood party,  just start talking about how video is superior to film.)

The fact is, each is superior in a number of ways; it depends on your needs.  And we also need to acknowledge the fact that much of the information about the "inferiority of video" is no longer valid.  (Even so, old beliefs persist.) 

Let's look first at the advantages of film.


Advantages of Film
 

Since the TV Production modules concentrate on television, we tend to emphasize the advantages of video. But someone is bound to ask: "Why is most  dramatic television shot on film.''

There are several reasons—starting with the historical.

After more than 100 years of 35mm film production, a rich and highly sophisticated tradition has grown up around film. Unlike video production where newcomers may quickly find themselves functioning as camerapersons and even in some cases as directors, the feature film tradition typically involves a long, highly-competitive apprenticeship which can extend over many years.

Less motivated people tend to drop out in favor of those who are more talented, persistent and dedicated.

Because of rich heritage of film, the production and postproduction processes have not suffered from a lack of talent or supporting industries. In Southern California alone there are thousands of companies that specialize in various aspects of film production.

Comparing the closing credits of a major film feature with those of a typical video production provides some measure of the differences that still exist between the two media. (Try sitting through the closing credits of Independence Day or The Titanic!)

For decades film has enjoyed consistent worldwide standards. A 16mm film can be broadcast on any of world's broadcast systems (regardless of the broadcast standard) and a 35mm film can be shown in almost any theater in the world.

Video, on the other hand, has not only progressed through numerous tape formats, but there are now a half-dozen incompatible broadcast standards being used in various parts of the world. For producers with an eye on international distribution, film has been the obvious choice for decades.

With the move to HDTV producers have seen in film a way of covering all of the bases: having a medium that can be used with in any of the SDTV, HDTV world standards.


Technical Quality Compared
 

It is commonly believed that  the quality of 35mm motion picture film (as viewed on television) is better than video. If we are talking about the artistic differences, then film has a definite advantage—for the historical reasons we've noted.

But as more and more film-style, video production is being done, especially in single-camera HDTV/DTV, this gap is disappearing.

Although artistic differences between film and videotape are difficult to measure, purely technical differences are not. This brings us to the following statement.

If production conditions are controlled and if comparisons are made solely on the basis of technical quality, the best 35mm film will be slightly inferior to the best video—assuming the latest professional-quality video equipment is used and final result is broadcast.

As controversial as this statement might be with film people, the reason becomes obvious when the production process for each medium is traced.

First, it is important to realize that if a signal from a video camera is recorded on the highest-quality process, no discernible difference will be noted between the picture coming from the camera and the picture that is later electronically reproduced.

With film intended for broadcast the process is far more complex.

First the image is recorded on negative film. The original negative film is used to make a master positive, or intermediate print. From the master positive a "dupe'' (duplicate) negative is created; and from that a positive release print is made. This adds up to a minimum of three generations.

At each step things happen: subtle color and quality variations are introduced by film emulsions and processing, there is a general optical degradation of the image, and the inevitable accumulation of dirt and scratches on the film surface starts.

After all of these steps, the film release print is projected into a video camera to convert it to an electronic signal—which is where the video signal started out in the first place.

To understand the film-video difference we must also bear several other factors in mind. Film is capable of resolving several times more detail than standard video. But since it looses much of its sharpness in its route from film camera to television camera, image enhancement is used when the film is converted to video.

Although image enhancement sharpens the overall look of the film image, subtle details, once lost, cannot be enhanced back into existence.

But sharpness isn't everything.

Many people think the slightly soft look associated with film on television is actually one of its advantages. The soft ambiance surrounding the film image is subconsciously if not consciously associated with "Hollywood film making.''

At the same time the slightly sharper image of video is associated with news and the live coverage of events, subject matter very much in contrast to the normal fare of feature films.

There is also a less obvious difference. With NTSC television the film-to-video conversion process requires some technical "fancy footwork" that  results in the introduction of almost subliminal effects associated with the film image on TV. (Recall that the NTSC standard is used in the U.S., Canada, Japan, and several other countries.)

NTSC video is transmitted at 30 frames per-second and film is recorded at 24 frames per-second.  (The machine shown on the left converts film to video.)  Since there is no nice, neat math associated with dividing 30 by 24, the only way to make the conversion is to regularly scan some film frames twice.  

This results in a subtle high-speed jitter, a type of artifact has become associated (if only subconsciously) with the film image on TV.

Incidentally, all of these film-video differences can (and have been) electronically duplicated with video—right down to the random specks of dirt associated with film!

With the SECAM and PAL broadcast standards used in non-NTSC countries the conversion process is easier.  Both of these systems operate at 25 frames per second—very close to the 24 fps used in film. Even when projected, the 1 fps difference is almost impossible to detect.

If the film is intended for broadcast, adjusting the film camera speed to 25 fps is a common solution.

Thus, non-NTSC systems—the systems used in the majority of countries—have an easier time making the film-to-video conversion. 


Film is Suited to the High-Definition Systems

A major advantage of the film image is associated with the need to convert programming to digital video and HDTV.   The old NTSC video images are limited by the NTSC process.  Trying to convert them to HDTV and digital images only magnifies the limitations of the NTSC system.

However, productions shot on film can be readily converted to the higher resolution formats and take full advantage of the increased resolution. And film originally shot in a wide-screen aspect ratio has an added advantage when converted to the 16:9 HDTV aspect ratio.

Interestingly, with the advent of high-definition video, we're seeing more video-to-film conversions—productions shot in a high-definition video standard and then converted to film.  In some tests digital video has been converted to 35mm film and projected in a theater.  Under test conditions audiences were hard-pressed to discern a quality difference.

In 1999, theaters experimented with using video projectors for showing feature films. Not only is there a great cost savings associated with this approach, but since material is delivered via a satellite link, live sporting events, rock concerts, etc. can also be featured.

As video projectors improve even more and costs come down, we will undoubtedly see theaters convert to video projection.


Coping With Brightness Ranges
 

Until recently, video cameras simply could not handle the brightness range of film. (Remember the 30:1 brightness range limitation of video?)

If film exposure is carefully controlled, a bright window in the background of a scene, for example, will not adversely affect the reproduction of surrounding tones. With the limited brightness range associated with tube-type video cameras the same bright window would significantly darken surrounding tones. (This same problem crops up with consumer and prosumer equipment that rely on automatic exposure circuitry.)

As a result of early experience with professional tube-based video cameras, many producers concluded that film had a major advantage over video.  However, when the latest generation of professional CCD cameras are manually setup (as opposed to relying on automatic settings) brightness range capabilities end up being similar to film.

In addition to brightness range there is also the issue of tonal rendition, or how different tones and colors will be reproduced. This can also be made to match film. Specifically, the tonal range of video at the top of the white range and in the shadow areas is expanded through the use of a dynamic contrast circuit.  When properly set up these circuits can handle video in excess of 600% over peak white without loss of picture detail, while still retaining detail in dark shadow areas.

In fact, if the "film look'' is important, there are camera adjustments and postproduction approaches that can make broadcast video indistinguishable from film.

Thus, the old arguments about video's limited brightness are, at best, questionable—at least with the latest generation of professional CCD cameras.  (In demanding still photography applications many photographers are finding that they can do a better job of retaining difficult tonal ranges with CCD-based still cameras than they can with film.)


Single-Camera, Multiple-Camera
Production Differences
 

Purely technical considerations aside, the primary underlying difference between film and video lies in the way it's shot.

Film is normally shot in a single-camera style, and video is normally shot using a multiple-camera production approach.

In film each scene can be carefully set up, staged, lit, rehearsed, and shot. Generally, a number of takes are made of each scene and the best one is edited into the final production. As they strive for perfection in today's high-budget feature film productions, some directors re-shoot scenes many times before they are satisfied.  (Possibly the record is held by one well-known film director who reportedly shot the same scene 87 times.)

Quite in contrast, video is generally shot with several cameras covering several angles simultaneously. Instead of lighting being optimized for one camera angle, it must hold up for three or more camera angles at the same time.  This means that it is generally lit in a rather flat manner, which sacrifices dimension and form.  And, with the exception of single-camera production, multiple takes in video are the exception rather than the rule.


Film and Videotape Costs 

The minute-for-minute cost of 16mm and 35mm film and processing is hundreds of times more than the cost of broadcast-quality video recording.

And, unlike film, tape is reusable, which results in even greater savings. But, this can also be a mixed blessing.

The tendency to reuse videotape means that the record of many events is lost when the tape is reused. This sometimes presents problems when attempts are made to do historical documentaries.

Offsetting the savings with video is the initial cost of video equipment. Depending on levels of sophistication, the initial investment in video production and postproduction equipment can easily be ten times the cost of film equipment. The cost of maintaining professional video equipment is also greater.

On the other hand, as we've noted, there is a substantial cost savings in using video for postproduction (special effects, editing, etc.). For these and other reasons film productions intended for television are routinely transferred to videotape. This transfer can take place as soon as the film comes out of the film processor.

Reversal of the negative film to a positive image, complete with needed color correction, can be done electronically as the film is being transferred to videotape. From this point on all editing and special effects are done by the video process. The negative film is then locked away in a film vault and kept in perfect condition.

Even for film productions intended for theatrical release, major time and cost savings can be realized by transferring the film to videotape for editing. Once edited, the videotape is then used as a "blueprint'' for editing the film.

Studio Production Standards

So-called digital cinema or e-cinematography (electronic cinematography) is rapidly gaining ground, especially since it is becoming almost impossible to distinguish between the two when they are projected.

Digital cinema seems to be moving toward two HDTV standards: 24p (24-frame progressive) and 60i (60-field interlaced).  The Sony camera on the left is capable of either of these standards.

Those who are after the "film look" prefer 24p, especially since the progressive approach results in fewer artifacts (aberrations) and higher resolution.  The 24 fps speed  is also the same as film—even though the extra sharpness of video sets it apart from film. (That extra sharpness has been termed "too real" by film purists.)

However, compared to 24p, 60i (30 fps) seems to do a better job of tracking motion, which means that zooms and camera movements—especially when done quickly—appear smoother.

Either of these standards can be converted to film.

At the same time we are seeing the beginning of a move to digital projection, or movie theaters that use video projection equipment.  Distributing digitized copies of films to theaters by satellite represents numerous advantages.
 

Will Video Replace Film?

So will video soon replace film for prime-time TV production?

Yes, eventually, just as it will eventually replace film in motion picture work. The move is well underway, as evidenced at the 2000 Sundance Film Festival.

But right now "Hollywood" has a tremendous investment in film technology. Plus, top creative personnel typically come from a film background.

But, as we've noted, things are changing, driven primarily by new technology and bottom-line economics.   


 

 

 

 
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