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Camera mounting equipment: In a supporting role - TvTechnology

Camera mounting equipment: In a supporting role

The broadcast engineer of today spends his time worrying about software, video servers, DTV and the continual upgrade of the facilities he manages. His
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The broadcast engineer of today spends his time worrying about software, video servers, DTV and the continual upgrade of the facilities he manages. His focus is on high-tech electronics and new ways to communicate like streaming video and business uses of the Internet. The advances in technology have changed his job in amazing ways and left a complicated profession that each of us struggles to stay current with each day.

In the studio and in the news van, the colleagues of the chief engineer concern themselves with other issues, which are no less important. Cameras, lenses and support equipment are the tools of the professional videographer, who we once called a cameraman. As the cameras and other tools of his trade have evolved, so have the less glamorous, but no less critical mechanical tools that are used every day. These contribute greatly to the ability of the videographer to be more efficient and work either alone or with a minimum number of other personnel on location for news or production shoots.

When lightweight cameras were first introduced, the only tripods and pan heads available for use with video cameras were those that came from the film industry. Conventional television cameras were considerably heavier than the largest film cameras in use and required "heavy iron" for support. A television pan head of the 1970s might have weighed 50 pounds by itself and, with a tripod and set of wheels, a single technician would have been making two trips to set up a rig. Film support equipment typically used wooden tripods and fluid drag pan heads. The news department of the TV station naturally simply pulled the film cameras off the tripods and put the similarly sized video cameras in their place.

Over the last 30 years, film has disappeared from the television station and with it the tools of the film cameraman's trade. Materials and technology have changed dramatically and the emergence of ever lighter and more portable video hardware has pushed the manufacturers of tripods and pan heads to develop a range of equipment that matches the cameras much better. Clearly, the pan head needed to move a studio video camera smoothly is inappropriate for the 10-pound camcorder used in the field.

Tripods The essential design of heavy-duty tripods has changed little in the last half century. Microwave transmitters and large studio cameras are still supported on massive metal tripods capable of holding hundreds of pounds. By the time a massive studio camera, large pan head and long zoom lens are stacked, the weight can easily exceed 150 pounds. Models with both cylindrical and rectangular cross sections remain as popular today as they were 30 years ago. These heavy-duty metal monsters remain the workhorse of large production vans used for sports and entertainment specials. They come in two-stage and "short-leg" versions to allow a range of camera position. Typically, they have the Mitchell mounting surfaces that evolved in the film industry. This allows a range of accessories that serve both industries to be used. If a jib arm is needed, a heavy-duty tripod is usually required, though some heavy-duty grip equipment may suffice.

At the other end of the scale, manufacturers have largely replaced the wooden adjustable tripod with ENG/EFP models made with hardened aluminum, magnesium and, most recently, carbon fiber materials. All provide long life and superior strength as compared to wooden designs or the metal tripods of a decade or two ago. Carbon fiber designs have superior strength and rigidity, and 20 percent less weight than aluminum. However, field repair is likely to mean replacing any damaged carbon fiber pieces.

It is important to consider the weight range when picking a system. It is obvious that you shouldn't load the videographer with unnecessary weight, but the operator will certainly tell you that they can optimize the smoothness of the camera's moves only when the pan head, tripod and camera are properly matched.

One last word. If you intend to use a tripod from one manufacturer and pan head from another make sure the mount is the same for both. "Claw ball" mounts come in 100mm and 150mm sizes. When the pan head is affixed to the tripod, the bowl allows freedom to level the pan head without the necessity of adjusting the tripod legs. Keep in mind that with flat, Mitchell-mount heavy-duty tripods, the legs must be adjusted because the mounting is fixed.

It is also important to remember that a simple monopod may well be the right choice for some shooting situations where mobility is critical or the space to put a tripod is just not available (like in a hot air balloon perhaps). A monopod is a simple shaft with adjustable length that is typically threaded right into the bottom of the camera for use.

Pan heads Pan heads have included just three generic varieties for a long time. The simplest mechanically is a post head. In this design the camera is mounted on a plate attached to an arm (usually flat) that runs along the side of the body and up to a pivot that is ideally mounted at the same height as the center of gravity of the camera/lens combination. That pivot is in a vertical "post" that is typically offset from the center of the tripod, but rotates in such a manner that the center of the rotation passes through the center of gravity of the camera. This is perhaps the ideal mount, but is also very rare in actual use.

A second variety uses simple pivots for azimuth at the top of the tripod, and altitude (tilt) a few inches higher. Springs are used to balance the camera throughout the tilt range, with a system of increasing tension. A well-designed pan head will allow great range of motion without a heavy over-center feel. Use caution though. A heavy camera tilted to one end may well make the entire tripod/head/camera assembly unstable. The general manager may not easily accept an explanation of the cool, straight-down shot that resulted in the loss of a camera.

The last variety is a variation on the simple design, but with cams that allow the center of gravity to be shifted fore and aft as the camera tilts. This allows the camera to remain balanced as the center of gravity moves forward when the camera tilts.

All of the designs are available with adjustable pan-and-tilt drag to make camera motion smooth with a variety of operator "touches." Fluid drag and liquid friction (LF) are often employed, with some designs utilizing simple variable friction adjustments.

Pan heads are designed for a range of uses, from the smallest of consumer crossover cameras to HDTV EFP cameras, and in a variety of price ranges. While some manufacturers have concentrated on the high end of the market and supply products known for quality and durability, for light duty use other manufacturers supply products with similar "operator feel" but substantially less cost. While generally not well known, one corporation owns a number of manufacturers of pan heads and tripods and even sells the identical product with different labels at different prices. A clever buyer can maximize value quite easily if the range of products desired is right.

Since I reviewed camera technology in the June 2000 issue there have been product introductions that are worth noting. One manufacturer introduced a 720p (1280x720 progressive scan, SMPTE 296) camcorder. The new design allows both 60fps and 30fps. I am not sure where 30fps is headed, but it is not much of a stretch to imagine a 720p/24 camcorder. A second manufacturer is now building HD camcorders utilizing DV compression at 100Mb/s.

In response to the same article one manufacturer corrected the pixel count utilized in their innovative multistandard HDTV camera. It actually contains 9.2 million pixels, instead of the figure of 6 million stated in the article. My apologies, and congratulations on pushing the envelope to and beyond the edge. As a hedge on formats this innovative design allows the image capture to be assembled in either progressive or interlace scanning depending on the way the CCD is read out and how pixels are combined. I wonder if someone is working on a 1920x4790 HDTV system?