Televising The Revolution

 A Reader Asks:

I notice a distinct chirping or buzzing in a defined, rhythmic pattern in the audio portion of my production. What causes this and is there anything that I can do to prevent it?

Many issues can cause chatter or noise in audio systems. Some of the most frustrating to deal with lately seem to be coming from portable wireless devices.

Cell-Cell-Cell

Cellular communication can be the source of this interference when a subscriber is using their wireless device near some speakers or poorly shielded audio cables, controls and other equipment that can resonate radio frequencies (RF). One of the biggest causes is shielding, or lack thereof. What is happening is poorly shielded gizmos can act like an antenna picking up the cell phone’s generated frequencies. At a very basic level, you are hearing someone’s telephone communication.

Some telephone networks cause more electronic noise than others because of things like, how often they communicate with devices, the frequency bands they use and how much power the device emits. 

The amount of noise caused by cell phones and networks when near sensitive audio devices is related to how efficiency the telephone communicates with the network and stays connected. Some telephones need to talk with the tower more often than others.

Experts say that the interference is an intrinsic part of cellular technology and not much can be done to prevent it. We live in a very noisy world from a radio frequency standpoint.

Fixes

Solving the issue is not easy. One thing that will help is to do away with copper cabling all together and install fiber optic cable but other hardware is still open to the problem. The best way is to insist that everyone within the production’s proximity turn-off his or her cellular devices. Not set to vibrate-Power-off completely! All well and good unless you pull up your mobile production unit near an offending system’s cell site.

Part of the responsibility lies with the manufacturers to provide better shielding and systems in their own devices. Part of the responsibility lies with audio and video system installers and designers to address this problem and design-in better RF shielding to prevent or at least minimize impact.

Try This

• Experiment with wire dress
• Be sure all shields are soldered
• Use quality cable.
• Use quality connectors 
• Maintain a totally balanced audio system
• Have a good maintenance program -33-

As you crank up your 500 watt surround sound amplifiers and digitally tuned, 96″, 1080 line, progressive scan, high definition television receiver and sink into your favorite movie or show, think back to September 7, 1927 for just a moment and maybe raise a glass in toast to a driven, young inventor who created one of the greatest devices of our age.

EIGHTY YEARS AGO 

It was eighty years ago today that a young scientist and inventor, Philo Taylor Farnsworth transmitted the image of a straight line from one empty tube to another empty tube. The technical wonder named television was born that day .    -33-

 It was announced today that the Cable Industry will be pumping $200M into advertising to educate consumers that the analog to digital cutover announced for February 17, 2009 will not affect cable subscribers.

EDUCATING CONSUMERS

According to the Associated Press, The $200 million advertising campaign includes both ads that have been purchased on broadcast channels and donated time from cable systems, the cable association said. It will run through the digital transition date.

The National Association of Broadcasters has pledged to begin its own campaign beginning in December.

FROM THE AIR

In a report from the Government Accountability Office dated 2005 about 19 percent or 20 million households rely on an antenna for over the air broadcasts rather than cable or other means of close circuit reception. See the story A Requiem For Analog TV elsewhere in the Televising The Revolution blog for more information. -33-

Imagine if you will. It is February 18, 2009. A television viewer receives TV over the air through a roof antenna. On awakening, instinctively the TV is turned on only to find snow-not outside but on the TV screen. Switching to another channel, snow… and another. Snow. Our viewer begins to fear that aliens really have landed in New Jersey as Orson Welles announced over 70 years ago.  Panic sets in as the radio is switched on, to just catch the news announcer saying “Analog TV died today. Film at Eleven.”  Nothing seems real. There is a sign post up ahead. It reads – You have reached the end of the Analog Zone.

Why Wasn’t I Warned?

You were warned. Didn’t you see the signs? Says the Federal Communications Commission (FCC) on their Website, “At midnight on February 17, 2009, federal law requires that all full-power television broadcast stations stop broadcasting in analog format and broadcast only in digital format.”

Broadcasters have been gearing up for this cutover for a long time. Unfortunately getting the word out to the public seems to be slow. Some sources say that only 20% of American viewers have heard about the end of analog TV.  Some people in the broadcast and television profession are even uninformed when asked about the digital transition.

What is the Digital Transition Date?

The digital transition date is the deadline for all US broadcast television stations to broadcast exclusively in a digital format. This means analog signals will no longer exist.

Will I Need a New TV set?

You should not, but if you receive your television stations only with an antenna you will need a converter box to convert the digital over the air signal to an analog signal so your TV can receive it. Alternately you will need a TV receiver with a tuner built-in that is capable of digital reception.

If you are old enough to remember when UHF stations with channels 14 and up started broadcasting but your television receiver only received stations from channel 2 through 13 on VHF it will be like Deja Vu. If you wanted to receive the “new” UHF stations you purchased a “Converter Box” which was attached to the antenna inputs on your TV and you tuned the higher channels with it. You should be able to procure a similar converter box to convert the new digital channels to your existing analog television receiver, attaching it either via your antenna terminals or your audio and video input.

If you rely on cable or satellite then the digital transition probably won’t affect you as much. 

Caveat Emptor

When purchasing a new TV from now on you should be sure it has a tuner capable of receiving digital television transmissions. Insist on it! If it does not it will not receive over the air, digital broadcasts when the day comes. Many televisions today have dual tuners for receiving both analog and the digital transmissions.

You will begin to find all kinds of great buys on TVs. Just be sure the set you purchase will not obsolete itself in a few short months. The old saying “Caveat Emptor” or Buyer Beware should be foremost in your mind.

Above all, don’t panic! It is not the end of the world, just the end of analog television. Knowledge replaces fear. Do your research. Ask questions and above all, be an informed consumer. -33-

Photography is magic. It has been since it’s beginnings and remains magic right up to today. There is a certain mystery to the way light sensitive particles in film or pixels on a silicone chip gather light and shadow to document a split second in eternity. Film based photography has its mysteries but those are mostly unlocked by chemists, scientists and photo lab technicians. Digital photography has its unknowns too. Some are left up to the engineers to solve but some are left to us, the everyday users. Most of us just want to shoot good pictures but are intimidated by things like megapixels, memory, white balance and other strange things we never heard of let alone had to worry about before.

There is so much to know about digital still camera technology that one can write volumes and still not offer a complete answer. Let us take a quick look at some of the basics and try to separate the hype from the facts.

Look for digital cameras that will perform well and not produce a ton of “noise” (grain) in the image. You should also consider a camera that will give you a good range of detail from deep shadows to the brightest areas in an image (This is known as Dynamic Range). Digital is great, but as of this writing it still cannot compete with film in its dynamic range. Once most digital camera users see what they have to go through to print a good picture after they click the shutter they suddenly realize how much their photo processor did with the negatives to make those good looking prints.

Megapixel Wars

Some camera ads will play on how many Mega Pixels (MP) a camera has. This may not be the best way to judge quality. For example a 6 MP point and shoot camera with a 4mm sensor is not the same as a 6 MP DSLR (Digital Single Lens Reflex) with a 14mm sensor. When it comes to sensors bigger is better. The larger sensor gives you better resolution and a much better signal to noise ratio with the same amount of advertised pixels. (Signal-To-Noise Ratio is the amount of noise you observe in an image versus the amount of clarity).

Color Balance

Another issue is white balance. White balance is the camera’s ability to see the color white, as our eye perceives white. This can be equated to using daylight or tungsten film, but with a much wider gamut. You want a camera with which you can adjust the white balance manually to fix those out of the norm indoor and outdoor shots.

Speed

Consider cameras that have a wide, and manually adjustable ISO range and shutter speed.
There is a speed of another sort and that is lens speed or the somewhat ambiguous “f.” Ideally you want a lens that will give you an f 2.0 or lower.

Speed again when it comes to write speed to the storage medium. You ideally want a fast write speed or you will be waiting for a long time for your camera to clear itself for the next picture.

Latency is another issue related to speed. Latency is how long it takes your camera to see the picture, focus, set the f-stop, capture and store the image once you push the shutter release. You want something that is near instantaneous. There may be some point and shoot cameras that might take upwards of 5 seconds to process a single image and store it in memory after you push the shutter button.

Modern cameras are designed to take most, if not all the burden of thinking about camera settings away from the user. This can be a wonderful feature, especially for neophytes or those of us who want to take a quick shot in ideal conditions. Sometimes you might want to “think” about your shot and customize your exposure and focus so you can get the best possible results. Auto settings are great when there is plenty of light and things don’t move or they don’t move very quickly.

Cam Bots

Some digital cameras can produce grainy images. Grain increase may be a factor of a camera’s “brain” automatically changing the ISO setting. When there is enough light it might be at ISO 200 when the light becomes low it might up the setting to ISO 1000 or greater. To see if this is what happens in your camera check the user manual and look for settings for Auto or Manual ISO, if there are you will want to set to Manual. You will then have to change the settings yourself for the amount of available light you have, but that might do great things to get rid of any grain issues. (Grain is actually a film term related to the size of the silver halide particles used in manufacturing film. Larger particles yield better low light performance but are grainy - Noise is a better term to use with digital cameras. Noise is the electro-optical manifestation of camera circuits making the pixels “work harder” to see in low light.)

Rule of thumb here for both film and digital is the lower the ISO number the clearer the image. Consider this too, the lower the number the longer your exposure time and/or the larger your aperture needs to be. You cannot expect to capture fast movement in low light conditions without sacrificing image quality. This is pretty much consistent with Film and Digital photography. Some digital cameras have a long exposure feature where it will actually squelch noise. See if your camera has this option and experiment with it.

Bad color can also be related to the above or it might be related to another automatic feature called “Auto White Balance.” Again, check your manual and see if you can change this feature to Manual and adjust the white balance yourself. Here is a rule of thumb to use when doing this:

3200 Degrees K = Tungsten stage lights & incandescent lighting in your home
5400 Degrees K = Daylight with blue sky at high noon
6000 Degrees K = Cloudy day, snow or light colored sandy beach
7000 Degrees K = Daylight in the shade - Photo Flash
9300 Degrees K = White on some high end computer monitors

Technology changes rapidly. Yesterday’s issues are solved in today’s cameras. Tomorrow it might be better than anyone imagined. One thing to remember when creating pictures. All this hardware is great but the camera itself is only a tool. It will not make you a good (or better) photographer. That bit of magic still remains in the very heart and imagination of the one who pushes the shutter button. -33-