Andy Ciddor /
04.07.2004 12:00 AM
HDTV Redefined
Now that high definition television is finally a reality, the fun really begins, as we decide what to do with all of those extra, digitally defined pixels. We have been hit with a double-whammy of picture definition with digital HDTV. Simply introducing a digital transport system removes many image degradation problems that have always been present in our analog dissemination systems. Even at NTSC's definition of about 480 x 440, digitally transported images are sharper. Adding more pixels per line and more lines gives us anywhere from around 50 percent more pixels in SDTV (480 x 640) to about 1,000 percent more in HDTV (1080 x 1920).

There are basically two things we can do with the extra pixels we now have at our disposal: We can show more things in our images, or we can show the same things in greater detail. In widescreen formats, the decision is slightly different, as the aspect ratio forces us to have either more things at the sides, or fewer things at the top of our pictures. (The implications of 16:9 images for set design, lighting, framing and shooting patterns, was the subject of a "Let There Be Lighting" column in October 2001.)

Sport, travel, action, drama, and many types of documentaries are natural candidates for choosing to include more things in our images. And let's face it, the wider format finally does give us the opportunity to frame a two-shot for television, with reasonably natural-looking spacing. However, many other types of programs, from our signature talking headshots, to game shows, reality TV, and news and current affairs in the field, are still going to require us to fill the screen with shots of people. Only now, those shots are in much higher definition, with as many as five times the number, of sharply reproduced, pixels.

It really should have come as no surprise that the result of this much closer scrutiny would be more detail in the images. Nevertheless, we are now starting to get a reaction from producers and presenters who want high definition pictures without an increase in definition.

We live in a society that tends to discard people and objects when they look old or feel out-of-date, and television is one of the main information channels for conveying that idea. We are always promoting and advertising the latest model; the newest, the most hip, and the most exciting. These are the very ideas that created the consumerism that has made the U.S. economy the strongest and most dynamic in the world. These are the driving forces behind the sales of so many products that promise to keep us from aging, and that drive public figures to undergo all manner of treatments and surgery to maintain an un-aging image. From my, somewhat jaundiced point-of-view on the world, there is a kind of karmic justice in the fact that our shining new, must have, high definition technology, is causing unease for those responsible for promoting those very changes.

As the real function of this column is to talk about how we can make good pictures, rather than poking fun at the insecurities of those poor souls on camera and their battle against the twin forces of gravity and time, let's look at the causes of their anxiety and what we can do about it.

SENSE OF ATMOSPHERE

Our role in lighting a picture is firstly, to provide enough illumination for an exposure, secondly, to provide modeling, shape and texture, thirdly to selectively reveal the image, and finally, to provide a sense of time, place and atmosphere.

In hit and run ENG, we may only make it to first base with a camera-mounted source, although it's not uncommon for us to get an opportunity to try for some modelling with a couple of lights on stands. In more controlled conditions on location and in the studio, we usually get a chance to go for a homerun and cover all four of our objectives. However, it is our requirement to model and shape our subjects that we need to re-examine if we are to assist in the process of minimizing the appearance of imperfections and the results of time and gravity.

In a two-dimensional medium such as television, film or still photography, we are deprived of the stereo images from our eyes that provide us with so much of the information about the depth of the world around us. We are left to draw conclusions about the depth in an image from such information as shadows, close objects obscuring our view of distant objects, and the diminished detail in objects that are further away.

Lighting's main contribution to depth information is its ability to create the shadows that tell us how far an object is above or below a reference point. As noses cast shadows on faces, we can tell that the nose is forward of the cheekbones, while eye sockets cast shadows on eyes, telling us that eyes are further back than eye sockets. Similarly, wrinkles, double-chins, and crow's-feet are at a different level to the surrounding skin and thus have shadows to announce their presence.

We could entirely eliminate the telltale shadows of wrinkles and crow's-feet and double-chins by simply lighting our talent's faces with banks of large-area softlights that create no shadows. Unfortunately the result would be a face with no cheekbones, eye sockets, nose, chin or lips. What we can do practically, is to keep our key lights (the shadow source) at a relatively low vertical angle, to minimize the depth of the shadows. The optimum angle is always a compromise between totally losing all depth information, throwing shadows all over the background like a cheap horror film, and causing so much glare that our talent either squints or can't read the prompting system.

In addition to optimizing the angle of the key lighting, we can adjust the angle and relative level of the fill lighting to control the depth of our shadows. Fill lights should be as soft (large area) as you can possibly make them, and should be as close to the axis of the lens as practicable. This may require the use of soft egg-crates on your softboxes to control the inevitable spill light. For ENG, at least one of your sources should be the biggest softbox you can manage to carry.

The depth of small shadows, as found in wrinkles, blemishes, laugh lines, crow's-feet, etc, can be further diminished through the use of contrast reduction filters. These include pieces of stocking/pantyhose, Ziploc baggies, clingwrap and proper lowcon optical filters, all of which are well-known for their abilities to reduce the resolution of an image, and thus hide blemishes.

Of course, you could resort to the use of automotive body-filler and sandpaper, botox injections, or plastic surgery to hide the blemishes completely, or you could employ younger, wrinkle-free talent. However, I will leave it at as exercise for the reader to sell these very practical solutions to your producer.


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