Wednesday, April 30, 2008

Recording Sound


Recording great-quality audio is no simple matter. Professional recording studios spend thousands (sometimes even millions) of dollars to set up acoustically superior sound rooms. I’m guessing you don’t have that kind of budgetary firepower handy, but if you’re recording your own sound, you can get pro-sounding results if you follow these basic tips:
  • Use an external microphone whenever possible. The microphones built in to modern camcorders have improved greatly in recent years, but they still present problems. They often record undesired ambient sound near the camcorder (such as audience members at a play) or even mechanical sound from the camcorder’s tape drive. If possible, connect an external microphone to the camcorder’s mic input.
  • Eliminate unwanted noise sources. If you must use the camcorder’s built-in mic, be aware of your movements and other things that can cause loud, distracting noises on tape. Problem items can include a loose lens cap banging around, your finger rubbing against the mic, wind blowing across the mic, and the swish-swish of those nylon workout pants you wore this morning. I discuss ambient noise in greater detail in the following section.
  • Obtain and use a high quality microphone. If you’re recording narration or other audio in your “studio” (also known as your office) use the best microphone you can afford. A good mic isn’t cheap, but it can make a huge difference in recording quality. The cheap little microphone that came with your computer probably provides very poor results.
  • Position the microphone for best quality. If possible, suspend the mic above the subject. This way the microphone will be less likely to pick up noises made by the subject’s clothes or bumping of the microphone stand.
  • Watch for trip hazards! In your haste to record great sound, don’t forget that your microphone cables can become a hazard on scene. Not only is this a safety hazard to anyone walking by, but if someone snags a cable, your equipment could be damaged as well. If necessary, bring along some duct tape to temporarily cover cables that run across the floor.
Earlier I mentioned that you should plan which video scenes you want to record. Planning the audio scenes that you want to record is also important. For example, suppose I want to make a video about a visit to the beach. In such a project I would like to have a consistent recording of waves crashing on the shore to use in the background. But if I record short, 5-to-10-second video clips, I’ll never get a single, consistent audio clip. So, in addition to my various video clips, I plan to record a single, unbroken clip of the ocean.

Avoiding timecode breaks


Each frame of video is identified using a number called a timecode. When you edit video on your computer, timecode identifies the exact places where you make edits. On your camcorder, a timecode indicator tells you how much video has been recorded on the tape. This indicator usually shows up in the camcorder’s viewfinder or the LCD panel. A typical timecode looks something like this:

00:07:18:07

This number stands for zero hours, seven minutes, eighteen seconds, and seven frames. If you have a 60-minute tape, timecode on that tape probably starts at 00:00:00:00 and ends at 00:59:59:29. In some cases, however, the timecode on a tape can become inconsistent. For example, suppose you record one minute of video, rewind the tape 20 seconds, and then start recording again. Depending on your camcorder, the timecode might count up to 00:00:40:00 and then start over at zero again. An inconsistency like this is called a timecode break. A timecode break is more likely to occur if you fastforward a tape past a blank, unrecorded section and then start recording again. When you capture video from a digital camcorder into your computer, the capture software reads the timecode from the tape in your camcorder. If the software encounters a timecode break, it will probably stop capture and be unable to capture any video past the break.
The best way to avoid timecode breaks is to make sure you don’t shuttle the tape (fast-forward or rewind it) between recording segments. An alternative approach is to pre-timecode your tapes before shooting. If you do have to rewind the tape — say, someone wants to see a playback of what you just recorded — make sure you cue the tape back to the end of the recorded video before you start recording again. Many camcorders have an end-search feature that automatically shuttles the tape to the end of the current timecode. Check your camcorder’s documentation to see whether it has such a feature.

Don’t abuse the zoom lens


Most camcorders have a handy zoom feature. A zoom lens is basically a lens with an adjustable focal length. A longer lens — also called a telephoto lens —makes far-away subjects appear closer. A shorter lens — also called a wide angle lens — allows more of a scene to fit in the shot. Zoom lenses allow you to adjust between wide-angle and telephoto.
Because the zoom feature is easy to use and fun to play with, amateur videographers tend to zoom in and out a lot. I recommend that you avoid zooming during a shot as much as possible. Overuse of the zoom lens not only disorients the viewer, it also creates focal and light problems whether you’re focusing the camera manually or using autofocus. Some zoom lens tips include
  • Avoid zooming whenever possible. I know how tempting it is to zoom in on something cool or interesting in a video shot, but you should exercise restraint whenever possible.
  • If you must zoom while recording, zoom slowly. You may need to practice a bit to get a feel for your camera’s zoom control.
  • Consider repositioning the camera instead of using the zoom lens to compose the shot. Wide-angle lenses (remember, when you zoom out you make the camcorder’s lens more of a wide-angle lens) have greater depth of field. This means more of the shot is in focus if you’re zoomed out. If you shoot subjects by zooming in on them from across a room, they may move in and out of focus. But if you move the camera in and zoom the lens out, focus will be less of a problem.

Friday, April 25, 2008

Your guide to the video camera revolution


Jennifer Dudley-Nicholson

WEDDINGS, parties and anything worth remembering will be filmed this year in a revolution spawned by a flood of tiny, advanced and inexpensive camcorders.

Even more camera makers are jumping on to the latest trend in video cameras, with heavyweights Canon and Sony releasing new camcorders that can record sharp video and fit comfortably in your pocket, just as Panasonic, JVC, Samsung and Sanyo have done recently.

But while manufacturers are falling over themselves to produce the technology, experts are warning that consumers need to be educated about the new generation of video cameras before they make the leap from still to moving memories, or from Flickr to YouTube.
Film school

This lack of education is something Canon recognised at its latest launch, with consumer imaging products marketing manager Stuart Poignand revealing the company had probed the market to discover why video cameras were not as popular as their still photo peers.

Mr Poignand said Canon's research found many consumers were simply overwhelmed by video camera options and obstacles.

"We found, and this is a really interesting statistic, 85 per cent of people don't own a video camera," he said.

"Unlike digital still cameras, there are a lot of barriers when it comes to owning a video camera. In the past some consumers have been disappointed with the footage they've taken. Also, what tends to happen after they film events is that they end up with this box of videotapes that is not seen by others.

"And they also know that if they don't edit the footage down they're going to bore everyone."

There are also many different recording formats in the camcorder market, Mr Poignand said, as well as several recording mediums, and little in-store information to help consumers choose the right camera for their needs.

Paul Curtis, executive director of the Photo Imaging Council of Australia, says the barriers to owning a video camera come from several fronts.

Many consumers, he said, might be reticent to invest in a new video camera after being burned by videotape technology in the past.

"I wasn't a big fan of videotape because of the moving parts involved and also the fact that it twists and it stretches, which can lead to problems," he said.

"Also, if you don't use videotapes for a long time, the layers of magnetic oxide interfere with one another and degrade the tape. If a videocassette is left flat rather than standing on its edge, the images on it will decay. That's how we lost a lot of the original TV shows."

Not great news for those wanting to preserve footage of their child's first steps, for example.

Editing footage captured on videotape was also tricky, often involving a complicated double-VCR set-up, an edit controller and a lot of patience.
Flash forward

Mr Curtis claims consumers burned by this old technology will be pleasantly surprised if they try out the latest generation of video cameras.

Flash memory, including Secure Digital (SD) memory cards, are "the most secure form of storage we know of", he said, and will stand the test of time better than videotape and even better than DVDs.

Video from these new cameras can also easily be imported to a computer for editing or plugged directly into a television.

Flash-based cameras also have other significant benefits over their older rivals.

Flash memory has no moving parts, unlike hard drives, making the technology less prone to failure and more able to withstand knocks. The technology is also quicker and uses less battery power than other memory and it takes up far less room than a hard drive, tape deck or DVD recording drive, allowing for far more compact camcorders.

Flash memory is also dropping significantly in price.

"With the way memory card prices are coming down I can see the day when people will keep their video stored on flash cards rather than reusing them," Mr Curtis said.

"They'll just buy more memory cards like we used to buy rolls of film."
New gadgets

The falling prices are also enticing more consumers to try out the new technology.

The Canon Digital Lifestyle Index, prepared by GfK Australia, found that digital camcorder prices fell by a "considerable" 16.9 per cent or $139.29 between the last quarter of 2007 and that of 2006, bringing their average price to just $685.

Mr Curtis said this price drop and increased competition would be sure to entice consumers to the market this year, predicting that Australians will buy more than 400,000 camcorders in 2008.

They will certainly be spoilt for choice, with most camera makers embracing flash technology.

Panasonic recently released a tiny SD camcorder called the S7 ($549) that features a 10x zoom in its tiny, 180g body, as well as a shock- and waterproof SD camcorder called the SW20 ($769).

JVC joined the trend with the colourful Everio G Series range of camcorders ($799) that can record to SD memory cards or a built-in 30GB hard disk drive, and Samsung released three new pint-sized camcorders, two of which record to SDHC memory cards or MMC cards ($1199 and $749).

Sanyo last year released a handheld high-definition camcorder called the HD1000 ($999) and Sony recently joined them, releasing the tiny HDRTG1 Handycam ($1599) which they claim is the smallest full-HD camcorder yet. It features a titanium body, face detection feature, zoom microphone and records images to a Memory Stick.

Sony also launched a second flash-memory camera, the HDRUX20 Handycam ($1599), that can record high-definition footage to a Memory Stick, a built-in 8GB flash memory or an AVCHD DVD disc.

And it's into this increasingly crowded market that Canon will launch its first flash-based video cameras in five days.

Canon's new range will feature three new flash-based cameras, all of which have tiny bodies that will record video to SD and SDHC memory cards. Two of these cameras will also boast a hidden surprise: 16GB of internal flash-based memory.

Canon digital video product manager Tamara Hohnberg says the camcorders' record-breaking internal memories will set the cameras apart from the crowded pack, and let consumers capture hours of video without spending a cent on recording media.

One of the new cameras, for example, can record up to 12 hours of full high-definition video on to its internal flash memory — something that would have taken 23 8cm DVD discs.

"Canon has been good at bringing high-quality goods to market, but often we're not the first to do so," Ms Hohnberg said.

"This is a first for us."

From home to the screen
The Canon HF10 ($1699) tops the new range, and can capture full high-definition video (1080p) as well as 3.1-megapixel still photos. It also features a 12x optical zoom, optical image stabiliser, Instant AutoFocus feature, HDMI connection, built-in light, and a 16GB internal flash memory in its 430g body.

Canon will also launch the FS11 camcorder ($899), with a 16GB built-in flash memory and image stabliser, and the FS100 ($699) that records directly to SDHC memory cards and weighs a tiny 310g.

An editing software package, Pixela ImageMixer 3 SE, will be included with all three cameras, to help consumers edit their videos and take some of the fear out of selecting a software suite.

Elissa Down, writer and director of the recent Australian feature film Black Balloon, believes these new flash-based video cameras will be a boon for documentary makers and home-video enthusiasts alike.

Down, who tested Canon's HF10 during a recent trip to Byron Bay, said the size of the cameras makes them unobtrusive and less likely to startle subjects, while their flash-based memory is easy on batteries and can capture a lot more footage than the average videotape.

"That's great, especially for docos," she said.

"When you're filming and you're getting good stuff you don't want to have to change the tape."

Down said new features like the ability to capture photos and videos simultaneously, and optical image stabilisation that "makes it look like you're not quite so drunk" will also prove handy for many users.

It could, however, mean a lot more drunken Australians feature on YouTube this year.

Thursday, April 24, 2008

How to Panning Effectively?


Moving the camera across a scene is called panning. You’ll often see home videos that are shot while the person holding the camcorder pans the camera back-and-forth and up-and-down, either to follow a moving subject or to show a lot of things that don’t fit in a single shot. This technique (if you can call it that) is called firehosing — usually not a good idea. Practice these rules when panning:
  • Pan only once per shot.
  • Start panning slowly, gradually speed up, and slow down again before stopping.
  • Slow down! Panning too quickly — say, over a landscape — is a common mistake.
  • If you have a cheap tripod, you may find it difficult to pan smoothly.
  • Try lubricating the tripod’s swivel head with WD-40 or silicon spray lubricant. If that doesn’t work, limit tripod use to stationary shots. Ideally you should use a higher-quality tripod with a fluid head for smooth .
  • If you’re shooting a moving subject, try moving the camera with the subject, rather than panning across a scene. Doing so reduces out-offocus issues with the camera lens, and helps keep the subject in-frame.

Shooting Video


Once your camcorder is configured and set up the way you want it, it’s time to start shooting some video. Yay! One of the most important things you’ll want to work on as you shoot video is to keep the image as stable as possible. Your camcorder probably has an image stabilization feature built in, but image stabilization can do only so much. I recommend using a tripod for all static shots, and a monopod or sling for moving shots.
Pay special attention to the camera’s perspective. As I mentioned the angle of the camera greatly affects the look and feel of the video you shoot. I often find that lowering the level of the camera greatly improves the image. Some high-end camcorders have handles on top that make shooting from a lower level easier. Virtually all digital camcorders have LCD panels that can be swiveled up so you can easily see what you’re recording, even if you’re holding the camera down low. Be especially careful to avoid letting the camera roll to one side or the other. This skews the video, which is extremely disorienting to the viewer. Try to keep the camera level with the horizon at all times. The following sections give additional recommendations for shooting better video. If you’re shooting a person in a studio-like situation, complete with a backdrop and fancy lighting, provide a stool for your subject to sit on. A stool will help your subject remain both still and relaxed during a long shoot, and (unlike a chair) a stool will also help the subject maintain a more erect posture.

Monday, April 21, 2008

Setting Up Your Camcorder


Perhaps the most important tip I can give you before you shoot your video is this: Know your camera. Even today’s least expensive digital camcorders are packed with features that were wildly advanced (and expensive) just a few years ago. Most digital camcorders include image stabilization, in-camera effects, and the ability to record 16-bit stereo audio. But these advanced features won’t do you much good if they aren’t turned on or configured properly. Spend a few hours reviewing the manual that came with your camcorder, and practice using every feature and setting. In particular, check the following:
  • Audio: Many new camcorders are set by default to record only 12-bit audio, also sometimes called the 32-KHz (kilohertz) setting. Fire up your camcorder right now and make sure that it is set to 16-bit (48KHz) audio instead, and never change it back. 16-bit audio is higher quality, and it won’t cause any problems later on when you want to capture video into your computer (or do pretty much anything else with it). For more on working with audio and understanding the bit and kilohertz settings.
  • Focus and exposure: In the previous section, I mention those times when you want to control focus and exposure manually. If you use manual focus or exposure control, switch them back to automatic before you turn off the camcorder. That way, the camcorder is ready for quick use later on when Bigfoot momentarily stumbles into your camp.
  • Special effects and exposure modes: As with manual focus and exposure, if for some reason you use any of the built-in effects in your camera, make sure you disable them before turning off the camcorder so that it will be ready to go the next time you use it. The same thing goes for special exposure modes.
  • Stow the lens cap securely: It seems obvious, I know, but if there is a clip or something that allows you to securely stow the camcorder’s lens cap, use it. If you let the cap hang loose on its string, it will probably bang into the microphone and other parts periodically, making a lot of noise you don’t want to record.
  • Use a new tape: Even though digital video doesn’t suffer from the same generational loss problems as analog video (where each play of the tape degrades the recording quality), various problems can still occur if you reuse digital tapes. Potential problems include timecode breaks (described later in this chapter) and physical troubles with the tape itself. Keep the camcorder manual in your gear bag when you hit the road. It may provide you with an invaluable reference when you’re shooting on location. Also, review the manual from time to time: Your camcorder no doubt has some useful or cool features that you forgot all about. If you’ve lost your manual, check the manufacturer’s Web site. You might be able to download a replacement manual.

Controlling Focus and Exposure


Virtually all modern camcorders include automatic exposure and focus controls. Automation is really handy most of the time, but it’s not perfect. If you always rely on auto focus, you will inevitably see the lens “hunting” for the right setting during some shots. This will happen a lot if you shoot moving subjects. Likewise, if you are shooting over a crowd or past other objects, the camera might focus on the closer objects instead of the desired subject. If your camera has a manual focus mode, you can avoid focus hunting by turning off auto focus.

Manual focus is pretty difficult to control if you’re using a small dial or slider switch on the side of a camcorder. Try to get a camera with a focus ring around the lens. This will make manual focus much easier to control.

I also urge you to learn how to use the manual exposure control (also called the iris). Exposure determines how much light is allowed to pass through the lens. It dilates and contracts much like the iris in a human eye. Manual exposure control allows you to fine tune exposure if the automatic control or camcorder presets aren’t providing the desired light levels. Some higher end digital camcorders have a helpful feature called a zebra pattern. As you adjust exposure, a striped pattern will appear in overexposed portions of the image. Overexposed areas will appear as washed-out, colorless white blobs in your video image. A zebra pattern makes controlling exposure a lot easier: I have found that overexposing a video shot when you are manually adjusting exposure is very easy

Although every camera is different, most camcorders have an infinite setting (∞) on the manual focus control. In most cases, anything that is more than about ten feet away will be in focus when the lens is set to infinite. Ten feet isn’t a long distance, so you may be able to resolve many focus problems by simply using the infinite setting.

Using lens filters



Your camcorder can probably accept some lens filters which screw on in front of the lens. Filters can be used to improve various lighting situations. For example, if you are shooting outdoors in a brightly sunlit location, you may find that colors look kind of washed out in the light. A neutral-density filter can compensate for the light and improve the way colors look.
Other lens filters can provide special lighting effects. For example, a star filter causes star patterns to shoot out from light points that appear in the image. This can give the scene a magical look. For more on how lens filters can change and improve the way your video images look, check out the Tiffen Web site at www.tiffen.com.

How to Deal with backlighting?


Among the most common lighting problems you’ll encounter when you shoot video are backlit situations. Backlit images occur when a relatively dark subject is shot against a relatively light background. The automatic exposure control in the camera adjusts exposure based primarily on that bright background, making the subject a dark, indistinguishable blob.
  • Avoid it: When possible, try to shoot subjects so that they are not in front of a bright background, such as the sky.
  • Fight light with light: Try to put more light on the subject. You may look silly toting a bright light around a sunny beach in the middle of the afternoon, but that is exactly what the pros do. If possible, try to shoot with the sun behind the camera.
  • Use camera settings: Many camcorders have settings that automatically compensate for backlighting by increasing exposure. The results aren’t always favorable, your camera probably has settings to accommodate many special lighting situations. Always read the camcorder’s documentation to see what features may be available to you — and practice using those features to see which ones work well and which ones don’t.

Understanding Diffusing light


Sometimes you may find that a light you’re using to illuminate a subject is too intense. This is especially common with key lights. If all you’re getting is a glaring white spot on your subject’s face, you can diffuse the light by putting something between it and your subject:
_ Cheesecloth: Available at art and cooking supply stores (and some grocery stores), cheesecloth has a coarse mesh and is useful both for diffusing light and straining beans or cottage cheese in the kitchen.
_ Translucent plastic: Sheets of translucent plastic are also available at arts and craft stores. Professional videographers call these gels. Colored gels are often placed in front of lights that illuminate a backdrop for special lighting effects. If you do this, make sure you place a barrier between your key light and the backdrop so the colored light from the gel isn’t washed out by the white key light. A barrier may simply be a piece of cardboard that is held up by a stand or helper. If you diffuse your light, you may have to move your lights closer to the subject.
Experiment for the best results.
Lights (especially halogen lights) tend to get very hot. To avoid fire hazards, you must use extreme care when placing gels or cheesecloth in front of lights. Never attach diffusers directly to lights. Position your diffusers some distance away from the lights so that they don’t melt or catch on fire, and check the condition of your lights and diffusers regularly. Read and heed all safety warnings on your lights before using them.

Thursday, April 10, 2008

Understanding bouncing light


Shining a light directly on a subject is not necessarily the best way to illuminate it. You can often get a more diffuse, flattering effect by bouncing light off a reflective surface. You can make reflectors out of a variety of materials, depending on what light effect you’re looking for:
  • Poster board: White poster board is a good, cheap material you can find just about anywhere. Thicker poster board is easier to work with because it’s rigid (meaning it won’t flop all over the place and make noise while a helper holds it). With some spray paint, paint one side of a poster board gold and the other silver. Experiment using each side to gain just the right light quality.
  • Aluminum foil: Crumple a large sheet of foil, and then spread it out again and tape it to a backing board. Crumpling the foil provides a more diffuse reflection than you can get from flat foil, but its reflection is still highly effective.
  • Black plastic garbage bag: Yep, black plastic bags are pretty good reflectors even though they have a dark color. As with foil, you can tape or staple the bag to a backing board to make it easier to work with.

How to Choose lights for Video Production?

Professional photographers and videographers typically use several different lights of varying type and intensity. Multiple light sources provide more control over shadows and image detail, and different kinds of lights have different affects. Lights that you’ll use break down into three basic types:
  • Incandescent: These are your good old-fashioned light bulbs like the ones Thomas Edison invented. Most of the light bulbs around your house are probably incandescent. Incandescent lights are usually cheap, but the light temperature is lower than with other types of lighting (meaning they are not as bright) and they usually provide wavering, inconsistent performance.
  • Halogen: Okay, technically halogen lights are also incandescent, but they usually burn at a much higher temperature (and provide a more consistent light over their lifetimes) than do regular bulbs. Many professional video-lighting systems are tungsten-halogen lights, which means they have a tungsten filament passing through a sealed tube of halogen gas. Good, cheap halogen work lights also work well for video lighting — and they are generally available at tool and hardware stores. Halogen work lights also sometimes come with useful stands, though you can make your own stands using threaded plastic pipe and clamps from your friendly neighborhood hardware store.
  • Fluorescent: Fluorescents also tend to give off a high-temperature light, though the temperature can vary greatly depending on the condition and age of the bulb. Fluorescent light is usually both very white and soft, making it ideal for video lighting. Fluorescent fixtures and bulbs can be purchased for less than $20 and can be easily suspended above your subject.
If you use fluorescent bulbs, let them warm up for a few minutes before shooting your video. This should prevent flicker. If the bulbs still flicker after they’ve warmed for a bit, try using new or different bulbs. Also, pay attention to how fluorescent lights affect your audio recordings. Fluorescent bulbs tend to produce a hum in audio recordings, so some practice and testing may be necessary. If fluorescent humming in your audio recording is a problem, record audio separately or use a different kind of light.

Dressing your cast for video success


My guess is that most of your video “shoots” will actually be pretty informal affairs, where you basically record an event that was scheduled to happen whether you brought your camcorder or not. Thus, you may have a hard time convincing everyone who is attending that they should dress appropriately for video. But there definitely are some types of clothes that work better in video than others — and if you have any control at all over what the people in your video wear, try making these suggestions:
  • Avoid clothes with lots of thin parallel lines or stripes: Thin parallel lines (like those you’d find on coarse corduroy or pinstripe suits) don’t get along well with TV screens; they create a crawling or wavy visual effect called a moirĂ© pattern.
  • Limit the use of very bright shades of red and blue. Red is especially problematic because it tends to bleed into neighboring portions of the video image. This doesn’t mean everyone in your movie should wear dark, drab colors, however. In the best of all possible shoots, your subjects’ clothing is bright enough to lend some interest, but contrasts with the background somewhat so they don’t get lost in the video image.

Friday, April 4, 2008

Evaluating Lighting

For the purposes of shooting video, light can be subdivided into two categories:
good light and bad light. Good light allows you to see your subject, and it flatters your subject by exposing details you want shown. Good light doesn’t completely eliminate shadows, but the shadows don’t dominate large portions of the subject either. Bad light, on the other hand, washes out color and creates lens flares (the reflections and bright spots that show up when the sun shines across the lens) and other undesired effects.

How to Compose a Shot?

Like a photograph, a great video image must be thoughtfully composed. Start by evaluating the type of shot you plan to take. Does the shot include people, landscapes, or some other subject? Consider what kind of tone or feel you want to achieve. F In the first shot, the camera looks down on the subject. Children are shot like this much too often: This approach makes them look smaller and inferior. The second shot is level with the subject and portrays him more favorably. The third shot looks up at the subject and makes him seem important, dominant, almost larger than life.

How to enlist video crew?

If you’re like me, most of your video shoots will actually be pretty informal, so assigning a director, sound engineer, and key grip probably seems a little silly. Besides, people who are formally assigned to such jobs will want special T-shirts and name tags and lattes and all kinds of other stuff that isn’t accounted for in your shoestring budget.
Still, you’re probably going to need some help —with setting up equipment, holding lighting props and microphones, standing guard to prevent passersby from walking in front of the camera, and (of course) hauling gear. I’ve found that my kids are extremely helpful when it comes to videography because they know that moviemaking is cool. (Why are children always smarter than everybody else?) You’ll want to take a few minutes to indoctrinate whomever you enlist for your video crew on the finer points of moviemaking and provide some dos and don’ts to follow while they’re on the set. Helpers should be trained on any equipment they’re going to use, and they should know where they can (and cannot) stand to avoid showing up in the picture. Anyone holding a microphone must be told that little hand movements may cause loud thumps and other noise; anyone holding a light reflector should be reminded to sit still lest strange shadows pan wildly back and forth on the scene.
Perhaps most importantly, remind all helpers that silence is golden. A camera lens may be limited to a specific field of vision, but a microphone isn’t. When little Johnny comes over to you behind the camera and whispers, “Daddy, I have to go to the bathroom,” his revelation will be recorded loud and clear on the tape.