From the Winter 1993 issue of the Operating Cameraman

The evolution process of the television system is very interesting. From the beginning of the commercial era, roughly the late 1940's, video production was always equipment sensitive. That is, production needs had to adapt to the system. In the early, postwar days, non-studio production took a lot of dedication to the job. Providing copious amounts of electricity for the equipment and lighting, running heavy camera cables and keeping touchy equipment cool was a daunting task to anyone not in love with a live broadcast.

Until the mid-1960's, the 3-inch image-orthicon (I-O) tube was the central element that permitted the conversion of a real-life image into an electronic signal that could be sent down a wire. The I-O tube, (like its 1920's predecessor, the iconoscope) works by focusing an image on a light sensitive plate which is scanned by a beam of electrons. The I-O camera produced a very good monochrome picture, but the equipment was bulky and often maintenance intensive. That is not to say that the cameras weren't reliable, because they were. They just needed a lot of attention.

Fortunately, the I-O tube was fairly sensitive, needing light levels of only 75 to 100 foot-candles. The tube's service duration was usually between 750 to 1000 hours and when it neared the end of its life, bright images would burn into the photosensitive surface and appear as a ghost when the camera was panned.

While these cameras performed well in brightly-lit situations, they generally worked best when the contrast range was contained. Whenever possible white was replaced with light blue or gray. It is interesting that the 3 1/2" I-O camera used 35mm format, "C" mount fixed lenses that were usually of very good quality. In the mid-1950's, RCA developed the TK-40, a color camera that used three image-orthicon tubes, one for each primary color. These cameras were enormous and severely limited the operator's ability to do anything quickly. They also required a lot of light. Two hundred fifty to five hundred foot-candles was common in a studio, placing a tremendous load on the air conditioning system, not to mention the talent.

The next big improvement in television cameras came in mid-1960's when the Dutch electronics company Philips introduced the Plumbicon pickup tube in its PC-60 color camera. Physically, the Philips camera took us back 15 years as their camera was about the same size and weight as the early monochrome cameras and had similar lighting requirements, around 75-125 foot-candles. It produced an excellent color picture for its day. Plumbicon cameras were designed from the beginning to use zoom lenses, which unfortunately, were often of less than stellar quality.

From the mid-60's through the late 70's, television cameras were pretty much unchanged. Advances in circuit design produced better quality and reliability, but the camera, no matter where it was used, was still a studio device. It needed lots of power, interconnect cables and a separate recorder that also needed lots of power, a maze of cables and an air compressor. But things were changing fast.

Micro-circuitry and small, low current pickup tubes allowed the design of very small, quality cameras. Probably the first to gain general acceptance was the the RCA TK-76. This 3-tube camera required regular attention to its color registration system, but when properly maintained it produced a very acceptable picture with no more support equipment than a charger for its 12-volt batteries. The operator, featured auto white balance manual or auto iris, and an internal color balancing filter wheel. What a concept. The operator had control of his picture.

Alas, the TK-76 still had to be connected to a separate recorder, but by the later 70's this was a portable 1" helical scan machine for optimum quality or a 3/4" cassette recorder. Both machines operated on 12-volt batteries so at last video was truly free of the studio, power and cable hassles.

TV station news departments embraced this new equipment because it cut down the time between shooting and airing a story. Add one small coaxial cable and the camera could be connected to a microwave van for live transmission, opening a whole new way to present news.

Other equipment manufacturers like Ikegami and Sony quickly jumped into the portable camera market, eclipsing the RCA TK-76. But it was Sony that changed video production forever with its Betacam.

The Betacam, which put location video production on the map, originally used three 2/3" saticon tubes. A saticon delivers very high resolution, performs adequately in low light, produces excellent color and it is fairly cheap to manufacture. The tube's biggest drawback is its image retention, similar to the old image orthicon tube. Very quickly, Sony updated the Betacam with a Plumbicon tube and it became the standard of the industry.

The beauty of the Betacam was that there was now a high-quality, go-anywhere, self-contained recording system. From the operator's standpoint, the Betacam gave us our freedom to record what we wanted to record. But along with this independence came the added responsibility of total quality control of our work, something that few video camera operators had experienced.

The Betacam also came along about the same time as the need for cheap television programming ballooned. Many production companies bought or leased a camera and an off-line editing system and were in the program business.

Of course the system was not perfect. Plumbicon cameras, like all tube cameras, have trouble handling bright areas, like white sky or specular reflections, that are 2 to 3 stops over the correct exposure for caucasian flesh tones. With electronic field production becoming big business the contrast problem was something we had to learn to live with or work around.

About seven years ago yet another innovation hit the scene, the charge-coupled device or chip. Although several manufacturers were working on chip cameras in the early 1980's, RCA was probably in the lead when they ceased production of broadcast equipment. Sony jumped into the market in the mid-80's with a chip Betacam, the BVP-5. Other manufacturers followed with chip cameras and we are now at the point where it would be difficult to find a new tube camera. The larger camera manufacturers have their own proprietary chip designs which are not really important here because they all work exceptionally well. What is important is that in just five years the chip has rendered every tube camera made for video production obsolete.

Today's chip cameras give the video operator the closest medium yet to film in many ways. The Sony 400 one-piece Betacam is roughly the same size as an Arri 16SR and I think it handles easier. Latest chip designs have almost no vices that intrude upon the needs of the production and within the last couple of years lens manufacturers are finally producing high quality optics for video use.

What's in the future? If you are not up on the latest in video technology, don't worry. Just go into any big consumer electronics store and look at the picture quality on some of the $1000 palm-corders. The distinction between professional and amateur equipment will blend, just like it did with 35mm still cameras. The only difference will be the skill of the person looking through the lens.