PRODUCTION

Introduction

Videotape is made of mylar, an extremely thin and flexible plastic. One side is coated with ferrous oxide, which is simply rust. This tape, when threaded through the machine appropriate to its format (1", Beta or Beta SP, also a format called MII), comes in contact with electromagnetic head(s) which either record the video/audio signal onto it, or play a previously recorded signal back.

Videotape formats common in current industry use are 1", D1, D2, D3, DCT, Beta (or Beta SP), and Digital Beta. Both Ampex and Sony manufacture 1" machines and tape. Ampex also created DCT, a digital format. D3, which is digital 1/2" is manufactured by Panasonic, while D1 and D2 are Sony digital 1" formats. Beta, Beta SP, and Digital Beta are also Sony products. SP stands for "superior performance"--instead of an iron oxide backing, SP tape uses metal particles to store the magnetic charge. Sony 3/4" (U-matic) cassettes are still somewhat in use, but mostly for playback of older material--1/2" equipment is better, lighter, cues up tapes faster, and is far more portable.

1" reel to reel analog tape was state of the art in the 80s, and many television stations still air certain programs from 1". Digital formats such as DCT, D1, D2, and D3 have been around for several years and are more expensive than 1" or Beta 1/2" analog cassettes: D1 and D2 are mostly used for graphics compositing and online editing. D2 has a function called "preread", which allows it to play back and record simultaneously. The record head "reads" the information it is about to record over and uses it as a source--the "from" source in a dissolve, for example. D3, though less expensive than either D1 or D2, is also a post-production format. As cost is often a factor in choosing which format to shoot and/or finish in, these tendencies are not set in stone.

 Digital Beta is fast replacing standard Beta or Beta SP, and the use of formats such as Hi-8 and digital Hi 8 is constantly increasing. As consumer products (digital Hi-8 among them) become more and more affordable and home-computer editing software better and more available, the differences between broadcast quality video and home video become less pronounced. A dedicated videographer willing to spend enough time and money could produce, shoot and edit something (which could be transferred to a broadcast format) and see his or her work on an other than public-access station. A few years ago this would not have been possible.Non-linear edit systems (see digital editing) currently are capable of producing masters of a quality equal to current on-air standards (that is, NTSC video, not HDTV) and are rapidly becoming the fastest, cheapest path from start to finish for high-quality productions. Of course, products keep changing and improving, and facilities that have somewhat recently completed millions of dollars in renovations are not eager to rip them out and replace them with the newest toys, so you will still see many linear edit suites in use. (see the post production suite)

One of the biggest drawbacks to consumer products is a direct result of one of their most attractive features--their size. Hi-8 and Digital Hi-8 tapes are very small in comparison to industry standard. This means that the tape and its signal-storing backing are thinner than in other formats. The tape is therefore more delicate--dropouts, which are flaws in the oxide backing of the tape, are more common and are often caused by repeated viewing of the material or shuttling back and forth at high speed. So professionals may often shoot on these formats, but transfer to sturdier mediums for repeated screening and editing. It's important to consider what the tape you are producing will ultimately be used for. If your audience will be viewing it from a VHS tape on a home machine, you will need to go to less expense than you will if you intend the piece to be aired on broadcast television.

The Camera

Video cameras come in two basic flavors--studio and handheld. Studio cameras are massive--they are usually mounted on a metal post rising from a heavy triangular base. The base sits on sturdy wheels which allow for easy movement on the studio floor, and the post allows for smooth pneumatic movements called "pedestal moves" up and down its axis. Camera operators either sit on a small stool attached to the camera mount, or stand. Sometimes a teleprompter is attached to a studio camera, allowing the "talent"--the actor or reporter--to see his or her lines. The camera operator views the scene from a viewfinder several inches wide, as opposed to the eyepiece the handheld operator must look through. The studio viewfinder has a 4:3 ratio width to height, the same as an NTSC television image. (see NTSC) This way, the operator can maneuver the camera around the studio floor while keeping an eye on any cables and equipment that could get in the way. Handheld cameras are smaller, lighter, cheaper, and--as the name implies--completely portable.

The camera lens is what lets in the light and focuses the image--a ring adjustment on the lens called the iris regulates how much light is let in, and the focus ring (also on the lens) sharpens or blurs the image. The pickup element, which is what changes the light entering the camera into the video signal exiting it, can be either a tube, 3 tubes (one each for red, green and blue), or a "charge-coupled device" also called CCD, which is a microchip. Cameras using a CCD to change the light into a video signal are referred to as "chip cameras".

When light hits the lens of the camera it is focused onto the pickup element. The target, a light-sensitive grid that is part of the pickup element, converts the image seen by the lens into a series of individual points (think of a Seurat painting). An electron gun reads, or "scans" each point, and converts them into electrical pulses, the voltage of which corresponds to the brightness of the area of the image being scanned. The process is reversed to recreate the image on a TV screen: the electrical pulses are converted back into points of light which are "painted" line by line by an electron beam onto the light-sensitive coating on the back of the television screen. Each line of coating is made of three tiny strips of phosphor--one red, one blue and one green, which are activated to accurately reproduce the color. (see also interlacing)

It's important to understand the nature of light. If you take pure red, pure green and pure blue light and add them together, you will get white light. This is referred to as an additive color mix. Red, green and blue are the primary colors, and all other colors in the light spectrum are created by some mixture of these colors. This is different, however, from mixing red, green and blue paint. Paint is not light, but pigment, and mixing pigment blocks out, or "subtracts" certain colors. So the mixing of pigments is referred to as a subtractive color mix.

There are some things you should never do with a camera and some things you should always do. Try, obviously, to not drop it, and never point the lens of the camera at a bright light. Modern chip cameras can generally handle a brighter spot of light than tube cameras, but it still isn't good for them. Training the camera on an intensely bright light can cause the light to streak across the image when you move the camera, and in some cases, can cause a permanent "burn" in the lens. You should always white balance your camera whenever you begin shooting or switch to a different location. White balancing involves pointing the camera at a white object--it can be an object in the scene you will be photographing, or a large white, non-reflective card. White balancing the camera gives it a value which it then compares to an internal reference of "white", and thus allows the camera to accurately recreate white (the presence of all light), black (the absence of all light), and colors (varying wavelengths of the spectrum).

You also need to be aware of something called color temperature, which becomes a factor when you mix different sources of light. Red light is of a longer wavelength than blue light--it is called "cool light", and film or videotape that has been shot with insufficient light (and is therefore underexposed) will have a reddish tinge. Blue light is "hot"--the wavelength is shorter and the light therefore more intense, and overexposed images will be too bluish. If you are shooting indoors under artificial light (which tends toward the cooler end of the spectrum), yet have a bright window in the scene, the window will appear washed out and blue. In addition, the contrast between the hot light of the sun coming in and the cool light of your natural indoor lighting will create a problem. Be sure not to place someone or something of importance to your shot directly in front of the window--the brightness of that light will cause the object(s) in front of it to be very dark by comparison and they will lose all detail. White balancing the camera does a good job of adjusting for too red or too blue light, but if you have a shot that needs to incorporate both indoor and outdoor light, you will have to compensate with additional lights or filters to bring the color temperatures more into range with each other.

The f-stop or aperture is analogous to the iris of the human eye: It is a ring that opens and closes to let in or keep out light, and the more light present, the more shut down the ring is. Smaller openings of the ring are expressed by a higher f-stop number--f16, or f22 for example, denotes a scene with bright light. A low f-stop number like f1.2 means the lens is wide open, admitting as much light as possible. The size of the f-stop opening has a secondary effect--depth-of-field: the larger the f-stop number (the more light available to the lens) the greater the depth of field, meaning that objects at a distance beyond or before the primary plane of the lens' focus will also be in focus. Many video cameras have an automatic control which adjusts the f-stop opening, but you may want to have manual control over the exposure. To begin with, it can be very distracting to see the picture get lighter or darker without some compelling narrative impetus--which leads to the next reason--you may also want control over your exposure for artistic effect.

The focal length of a lens (meaning whether it is used for a wide-angle view or a close-up) also affects depth-of-field. Video cameras come with a zoom lens, which can pull back for a wide angle but zoom into the subject for a close up. Wide angle shots (35 or 50mm for example) have great depth-of-field, and very often everything in the shot from the foreground to the background are in sharp focus. A close-up however, may keep only the subject of the shot in focus, and then only if the subject does not move closer to or further back from the lens.

The Video Signal

If the pickup element in the camera is a chip, the chip takes the color information (how much red, green and blue is hitting each point on the target), stores it in its built-in memory, then sends it out dot by dot, line by line. If the pickup element is a tube, the process is much the same as with a chip. Chip and single tube cameras have a filter to process the light into its primary colors, but if the camera has 3 tubes, a beam splitter breaks the image down into three images--one each for red, green and blue. Three separate pickup elelments then focus each image on its respective target, and translate the information into three separate signals, as opposed to one. A video signal that has splits the color information into its individual red, green and blue values and separates it from the black and white information is referred to as a component signal. Component video is far superior to a composite signal, which bundles the components together with the black and white information.

The video signal includes four pieces of information: luminance, which is the black and white information, and chrominance, the information about red, green and blue, which in some combination thereof create all the colors of the spectrum. A composite signal lumps all this information together and transmits it over one cable. But a component system transmits the information over three wires. How does it relay four elements over three wires? It breaks the information down this way: luminance is expressed by the letter Y, the red signal minus the luminance information is expressed as R-Y, and the blue signal minus the luminance is expressed as B-Y. With these three signals, the color green can be computed. The pure RGB (red, green and blue) signal is used for sophisticated paint and animation systems, and is superior even to a standard component signal. But RGB is translated into Y, R-Y, B-Y for recording onto videotape. Y/C is a fourth (1. composite, 2. component, 3. RGB) method of recording. It is used in VHS, S-VHS and Hi-8, and is also called "color under". Y/C separates the signal into two parts--luminance (Y) and all color (C).

Recall that the camera takes the original image hitting the lens and focuses the image onto a grid called the target. The target sees the image as a sequence of dots moving left to right to form a line, and it takes 525 lines to go from the top of the image to the bottom . For the picture to be played back onto a television screen, the process is reversed--the electron beam, which is what reads, or scans each line, takes the information and transmits it onto the back of the screen, which is coated with light sensitive phosphor. The electron beam triggers the phosphor to display the values of red, green and blue contained in each dot of each line. It repeats this process 525 times. When it has scanned 525 lines, it has recreated one frame of video, and it does this 30 times per second. The electron beam, however, does not scan the lines sequentially, but reads the odd-numbered lines first, then returns to the top of the screen and scans the even-numbered lines. Thus it divides the 525 lines which equal one frame of video into two fields. This process is known as interlaced scanning. The reason this is done is because if the frame were not broken up into two fields, the first painted lines would begin to fade by the time the beam got around to painting the last ones, and our brains would perceive a flicker in the image. So the information is divided into two separate fields, which are then "interlaced" together. The phenomenon of "persistance of vision" allows us to see these individual fields and frames as continuous motion.
When the electron beam, or "gun" finishes tracing one line, it shuts off and moves back to the other side of the screen, to the beginning of the next line it will scan. The period of time during which the gun is turned off is referred to as the horizontal blanking interval. During this interval "color burst", which is a color reference signal, and "horizontal sync pulses", which regulate the timing and placement of the gun are sent. When the gun reaches the end of one field (which takes 1/60th of a second), it turns off and returns to the top of the screen where it begins the process of scanning another field. The time when the gun is turned off in this case is called the vertical blanking interval, and it is used to relay "equalizing pulses" (information about the particular field of video being scanned) and "vertical synchronizing pulses", which again regulate the timing and placement of the beam. Additional information, such as closed-captioning or vertical interval time code (VITC) can be encoded in the vertical blanking interval.

 Both horizontal blanking and vertical blanking have set dimensions. Horizontal blanking is originally set in the camera, but it increases each time a tape is copied, and may result in visible error (the picture does not reach to the edge of the screen) if a tape is down several generations. But this is a problem only in an analog recording. Digital recording does not compound a blanking error, or any error for that matter, because the digital process recreates the signal anew each time.

In an analog system, the composite or component signal is "modulated", that is, it is altered for the purpose of encoding it onto a "carrier frequency", which is capable of carrying or transmitting it. This frequency is called RF, for "radio frequency". The signal can be transported from camera to recording machine or directly to the air, or from a machine to air, but an analog recording or playback receives or transmits a signal using RF. In the case of a recording, the signal is directed to an electromagnet contained in the recording head. The video signal magnetizes the recording head, which passes the charge onto the oxide backing of the videotape as it glides over the head. During playback, the magnetic charges on the tape are relayed onto the playback head, amplified, and then "de-modulated"--that is, decoded from RF back to the video signal. Modern recording heads are called "helical scan" or "slant track", because they lay down and pick up the signals by runningacross the tape at an angle instead of perpendicular to it. Since more tape passes across the head during the course of a single revolution of the head, the tape can be narrower and still contain all the information it needs to.

In an analog recording, each time the head passes across the tape it lays down one field of video. Two fields of video equals one frame, 30 frames equals one second of video. There are two types of recording that can be done, depending on whether or not the tape has a pre-recorded signal called control track on it. Control track is often referred to as "electronic sprocket holes", because it is control track, (also called a "frame pulse") that regulates the playback speed of the tape. A blank tape has no control track on it. If a tape has control track on it, it can be used for insert editing but if not, it can only be used for either assemble editing or an assemble record, which is usually referred to simply as "record" or "hard record". (see analog editing) Any synchronous signal--that is, any signal that conforms to the specifications of the video signal--can be used for control track, which is laid down continuously for as long as a machine is in hard record mode. A machine making an assemble record will, when stopped, break control track. Once the machine goes into record mode again it will be laying down control track, but if you were to play back that stop in the recording, your picture would break up. Since a machine plays back by locking to the control track, the brief disruption in control track is enough to cause it to lose stability.

Another signal that is laid onto the tape during recording is time code. Time code is a signal placed on every frame of video for the purpose of giving each frame a unique indentification number. Time code is marked in the format of hours:minutes:seconds:frames, so a time code of 16:52:48:10 is read as "16 hours, 52 minutes, 48 seconds and 10 frames". A machine can be programmed to cue up to this exact frame of video, or execute an edit or effect beginning there, or these numbers can be used to describe where on the tape a particular shot can be found. You can record time-of day time code or you can, if you have multiple reels of tape, record the first one with time code beginning at hour 1, the second with time code beginning at hour 2, etc.

Time code can either be drop frame or non-drop frame. With non-drop frame time code, frames are numbered from 0 to 29. Since thirty frames equals one second, the frame counter returns to the number 0 after 29, and the second counter advances one, to indicate one second of video. Drop frame is a little more complicated. We say that video travels at 30 frames per second, but in reality it travels at 29.97 seconds. Over the course of one hour, this slight time discrepancy accumulates to 3.6 seconds, a sizable amount, which of course would be compounded x24 over the course of a single day. To account for this difference, drop frame time code drops two frames (:00 and :01) every minute except at 10-minute marks (10 minutes, 20 minutes, etc.). This results in accurate time-of-day code, and one hour of videotape lasting exactly one hour. Drop frame time code is only used by broadcast networks, which have to strictly adhere to an accurate clock.

There are several different possible locations for time code on the tape. Longitudinal time code, or LTC, is recorded on one of the audio tracks, and is the most frequently used. "Address track" time code is the format used by Sony 3/4, (U-matic) cassette players, and is recorded at a different frequency from video information but at the same place on the tape. VITC, or vertical interval time code is recorded in the vertical blanking interval, but not all machines are equipped to record or play back VITC. VITC can also contain something called user bits, which are hexadecimal (the letters A-F, the numbers 0-9) characters that encode additional information.

Time code is laid onto the tape by means of an internal (within the record machine) or external time code generator. When making a copy of a particular tape, if you want to record the same time code as exists on the playback, it is important to regenerate that time code--that is, to slave the generator to the numbers coming off of your playback tape, and lay a fresh signal of these same numbers onto your new recording. Time code must be synchronous, which means that the generator must be locked to the record machine, or they must both be locked to an external signal. (see genlock) If time code does not accurately label each of the two field per frame of video, it is said to "drift", and it will be useless for editing purposes.

Lighting

Modern video cameras are able to adjust to very low lighting conditions, but not without consequences. In the case of less-than-adequate light, the lens may be able to open wide enough for an image to be made out, but because the video level will be weak (meaning the amount of white, or luminance in the picture) will not come close to the 100 IRE measurement on a waveform monitor (see scopes & timebase correctors ), the result will be a low "signal-to-noise" ratio. The picture will appear grainy, and it will be hard to differentiate colors. Sometimes of course, this may be the intended effect.

Another potential problem is the ratio between dark and light areas of the picture, or the contrast ratio. Setting the proper exposure for a high-contrast scene can be tricky. Natural sunlight coming through a window will result in the underexposure and consequent loss of detail of anything (darker) standing in front of it. In addition, your video may show problems related to color temperature, which are not visible to the naked eye. Areas of high-contrast that also have great detail (many leaves moving against a bright sky, for example) may prove too much for the camera's resolution, and show artifacts. (see artifacts)

Proper indoor exposure is best accomplished with the use of three lights: key, fill and back. The key light is bright, and is responsible for providing most of the light necessary to the scene. It should shine on the subject from an angle rather than head on, and shouldn't too high or too low in relation to the subject. The key light will cast shadows that give the subject desired dimension, but improper placement of the key will cause distracting shadows. The fill light balances the key, softening the shadows cast by the key. The fill should be less intense than the key, and in most cases will come from the opposite angle. The back light will separate the subject from the background, and as its name implies, comes from behind.

Lights are basically "directional", casting a focused beam--called a spot--or "soft", filling the area with light--called a flood. Key light is usually a spot, while fill and back are floods, but this is not a hard and fast rule. Lighting is an art as much as a science, and you should experiment (bearing in mind technical considerations like contrast ratio and color temperature), looking through the viewfinder to see the effects of your lighting. You can use the automatic iris on your camera or, for the more advanced, light meters, which measure either reflected light (light bouncing off your subject or any object) or incident light (coming directly from a light source). When using light meters, always take several readings so you have an idea of the light throughout your scene, but in cases of varying readings, err on the side of skin tone, so the people in your scene will be properly exposed. There are many lighting accessories--barndoors, flags, umbrellas, filters, gels, reflectors--that allow to you adjust, direct, reflect, block out or distribute light, and these can be makeshift as well as part of a professional lighting kit.

The Audio Signal

Sound is the movement of molecules in a physical medium such as air. It is an analog signal, meaning that it is continuous, and it travels in waves. The vibration of the molecules nearest the source of the sound cause a compression of the adjacent molecules, causing them in turn, to compress the molecules they touch. When compression reaches its peak, the molecules pull away from each other. This is called "rarefaction". Each high and low of compression and rarefaction is referred to as a cycle of the wave. The strength of the wave (which results in the number of molecules displaced by it) is its "amplitude" or volume, and the number of times per second it occurs is its "frequency".

Amplitude (volume) is measured in decibels or dB. Videotape machines measure the strength of the audio signal being recorded or playing back with a "volume unit" or VU meter. Though varying levels of sound are acceptable (depending on the loudness of the sound itself), sound recorded at too low a volume--narration and dialog, for example, or music--will need to be boosted in order to be heard, resulting in an increase in the signal-to-noise ratio. (see signal-to-noise) Sometimes there is no way to avoid having to raise audio levels, but the resulting noise can often be filtered out through a mixer. Far more problematic than low audio is uneven audio, or audio that is too high or "hot", which is referred to as "overmodulated". Overmodulated audio that causes the needle on the VU meter to repeatedly pin the high end of the red zone will be distorted, and frequently unusable. Many record machines have a control called a limiter which will suppress audio volume above a certain threshold. But using the limiter often results in distortion as well, so it is recommended to keep it in the off position, and set incoming audio to its proper level instead. As a rule, dialog and narration should peak at about +1dB on the VU meter, background audio (such as music or natural sound) should be recorded at about -20 to -30dB. Digital formats (D1, D2, D3, Digital Beta) as well as MII and Beta SP all have four available tracks of audio, standard Beta and S-VHS have two.

The actual location where the sound is being recorded has a tremendous effect on its quality, and can often cause unexpected problems. Because sound is vibration, it bounces off of hard surfaces. Audio recorded in a room with carpets, upholstered furniture and heavy curtains may sound muffled or low, because the porousness of the materials absorb much of the sound wave. Proper microphone placement can help adjust for this. An even greater problem than sound absorption is sound reflection, which happens when the physical location of the audio being recorded is full of hard surfaces, like a gymnasium. The audio will bounce off of these surfaces and sound echo-y and unnatural, lacking depth and fullness. A location with many hard, reflective surfaces is referred to as being "live". Again, proper microphone placement can help, but this problem will need to fixed by equalization on a mixer. (see equalization)

Microphones

Microphones transduce, or change acoustic energy into electrical energy. The "element" is the part of the microphone that actually does the transducing, and is analogous to the pickup element in the camera lens. There are three different types of microphones commonly used professionally and they are named after their transducers: moving-coil, ribbon, and capacitor, or consenser mics.

 Once the acoustic energy has been changed into electrical energy, the electrical energy travels as voltage. Professional mictrophones are referred to as "low-impedance", meaning that there is little resistance, or impedance, to the current flowing within them. Low-impedance microphones are used because they incur fewer problems in the way of "hum" and static which can occur in electrical fields. Low-impedance mics can also be cabled over long distances without a deterioration of the audio signal. (see also signal-to-noise ratio)

If your microphone is producing weak, buzzing or highly distorted audio you may have the amplifying device it is plugged into set at an impedance (resistance) which does not match that of the microphone. Audio consoles and tape decks have line/mic input switches which change the impedance, so check that this is correctly set. Flourescent lighting fixtures and other electrical devices can cause interference with the audio signal, resulting in a hum. (Audio speakers placed too closely to a television set or monitor will do this.) Make sure that your microphone cables intersect electrical wires at 90 degree angles--do not run them parallel. If your audio crackles, there may be a problem with the wires inside a cable or the microphone itself. Dirty "pots" or "potentiometers", which are volume or directional controls on audio consoles can cause crackling, too. Turn the pots quickly back and forth--if you hear crackle this is almost certainly the cause of your problem.

 If you have more than one microphone in a set up and your audio level still seems low, you may have a "phasing problem". Sound travels in waves, with a positive portion and a negative portion to each cycle of a wave. If one microphone is picking up the positive portion of the wave while the other is picking up the negative portion, they can cancel each other out. Move the mics around--this will often solve the problem.

Moving-coil microphones transduce acoustical energy by means of suspending a mylar (a thin plastic) sheath with a wire coil attached in a magnetic field. Sound waves cause the sheath, or "diaphragm" to move, which in turn moves the wire coil. The movement of the coil in the magnetic field causes it to become charged. Moving-coil microphones are hardy and don't add significant noise to their signal and are somewhat cheaper than other types. However, they are not usually very responsive; because the transducing mechanism within the microphone has more mass than in other types of mics it can't always vibrate fast enough to reproduce the higher frequencies. Some sounds will literally lack vibrance. In general, audio reproduction is less accurate with moving-coil microphones than with other types, especially with sounds that begin loudly and then fade quickly, but it is what many reporters in the field use because it is a sturdy mic and not overly sensitive to wind.

Ribbon microphones replace the diaphragm and moving coil with a thin metal ribbon, which picks up voltage as it vibrates within the magnetic field in response to sound waves. While older ribbon microphones tended to be very fragile, newer designs have resulted in a sturdier microphone less likely to be damaged by the blasts in pressure caused by loud sounds. Ribbon microphones are used mostly for music and voice recording and live performance. Even the newer models are delicate and can be destroyed by a sudden loud noise. Ribbon mics themselves do not add noise to their signal, but their output is very low. If the microphone is too far from the source or connected to the recording device by a long cable, the signal can get noisy.

Capacitor, or condenser microphones transduce acoustical energy to electrical, rather than electromagnetic energy, as do moving-coil and ribbon mics. A capacitor is something capable of holding on to an electrical charge. Condenser mics have a thin moving diaphragm which is positioned parallel to a fixed plate. This is the capacitor. Sound waves move the metalized diaphragm back and forth--the voltage of the resulting electrical charge causes the variation in the signal output. Capacitor microphones create a high-impedance signal and need to be amplified, so these mics always need a separate power supply. Modern condenser microphones use batteries to supply the needed voltage. These microphones tend to be the most expensive of the three types, but they are the most responsive to both high and low frequency sounds, and they are capable of picking up sound from a greater distance without adding noise to the signal than are the others.

The pickup pattern of a microphone refers to the direction(s) from which the microphone is best able to pick up sound. An "omnidirectional" mic picks up sound equally well from any direction, "bidirectional" from the front and the back, and "unidirectional" from one direction--the front--only. "Cardioid", which literally means "heart-shaped" is another name for unidirectional microphones.

Lavaliere microphones are the small objects pinned to jacket lapels or ties during on-camera interviews. While they are very good at picking up realistic, well-rounded sound, if the speaker's clothing brushes against the microphone it will produce a loud, distracting rustle. Because lavalieres are so unobtrusive, people often forget they are wearing them--they may move their hands alot and knock into the mic, which can sound like a small explosion. Still, lavs produce the best sound for the situation, and they are relatively inexpensive.

 A shotgun mic is a very long narrow cardioid (unidirectional) microphone. Unidirectional mics are almost always long and narrow, because the way the are able to focus the pickup pattern so narrowly is by cancelling out the sound coming from other directions. They do this by means of holes on the sides of the microphone. The sound coming in is altered so it becomes out of phase, thereby dropping out of hearing and pickup range. Shotgun mics are often suspended from a long pole called a "boom". The boom is held just out of camera range, pointing toward the source of the sound. Often a microphone attached to a boom is itself called "the boom".

 Hand-held microphones are the kind used by reporters--sturdy, moving-coil type generally, not overly sensitive to movement or wind. Studio microphones are usually ribbon type--found either in a soundproof narration booth or in a recording location where the fragile mic does not have to be moved very often.

 Wireless microphones transmit a weak signal to an amplifier which boosts it to the proper recording level. Wireless mics can be handheld as well as lavaliere, and are of obvious value when the audio source needs to be free of trailing cables.

Cables and Connectors

All record decks include connectors for bringing signals in and for sending them out. There will be more than one way to bring a video signal into or out of the machine--composite or component or S-VHS. (see S-VHS) The connector panel is on the back of the record deck, but often, if the machine is frequently used to record feeds from a variety of sources, the machine's input and output jacks may be "remoted" to a something called a patch panel or patch bay. This is a row or rows of inputs and outputs that have been hard-wired to various positions on the panel. One takes a "patch cord" and routes the output of a particular source into the input of the desired destination. Patch bays are used for both audio and video.

Camera cable connectors are multi-pin, with each pin connected to a different wire within the cable. Each wire in the cable carries part of the signal--one or another channel of audio, sync information, etc. Tape machines also have multi-pin connectors to delegate remote control to edit controllers.

RF connectors are used with cables carrying a combined audio and video signal. They are used to connect a VCR to a television, for example. The signal is carried by co-axial cable. The RF connector has a single pin or wire protruding--this wire goes into an RF receptor which has a hole in the center to receive the wire. A threaded ring on the end of the co-axial cable screws onto the RF receptor to tighten the connection.

BNC Connector

A BNC connector is similar to an RF connector in that it also has a center pin and is used with co-axial cable, but it is used for video only, and has a different type of locking ring. BNC connectors are also called 'bayonet connectors".

Male RCA Connector

RCA connectors are frequently used with cables carrying line level (as opposed to mic level) audio, though consumer cameras use RCA connectors to input and output video as well. Video cables often have an RCA connector on one end and a BNC on the other. RCA connectors come in two varieties-- "male", which have a extending piece of metal or "female", which have a hole into which this extension fits.

Male XLR ConnectorXLR connectors are used exclusively to carry and connect audio--both line and mic level. It is common to see an audio cable with an RCA connector on one end and an XLR connector on the other. XLR connectors also come in two varieties-- "male", which have 3 extending pieces of metal or "female", which have 3 corresponding holes into which these extensions fit.

1/4Mini Phone Plug1/4" phone connectors and miniphone connectors (called "minis") are used to connect line or mic level audio. Stereo headphones can use either phone plugs or minis. Computer microphones use mini connectors. If there are two colored rings on the plug it is stereo--one colored ring means it is mono.

Firewire ConnectorFirewire connectors provide digital to digital input and output, and are relatively new. Most new consumer cameras have a firewire port, and desktop video editing software allows for importing video via firewire.