Cameras in the Classroom
7/15/2003 By: Bruce A. Johnson
I've recently been working on an instructional video program for teachers called "Teaching Through Technology." I've observed many tech-ed programs throughout the state of Wisconsin, and have been struck by the realization that the best of these programs aren't just about videography, or editing, or writing-they are truly multi-disciplinary. Creating alliances and collaborations throughout the school-with the music department, the drama department, the English department, the athletic department, and others-is a natural way to create a curriculum that will really teach your kids the things they need to not only produce excellent video content, but to be discerning media consumers as well. I believe this is a skill that is rare in our society today, and will only become more important in the years to come.
Shooting "Teaching Through Technology" for the Wisconsin Educational Communications Board has proven to me the video camera can be a powerful tool in education, whether it's used to do school "news coverage," shoot game film for the sports teams, or just give the kids an option to the standard term paper or book report. Let's look at the technologies that are making this a reality.
Let's time-travel back to the early 1970s. In my suburban New Hampshire school district, we weren't blessed with the latest in technology, but we did have what I believed to be the pinnacle of cool: a black & white, reel-to-reel Sony PortaPak video system, along with a second playback deck. I was in heaven whenever I was sent out with it. What power! What responsibility!
What primitive technology!
Today, it's a pretty safe bet that 25 to 50 percent of your students have, in their homes, color video cameras that make my monochrome PortaPak look like the dinosaur it is. And a large percentage of your students have video editing capabilities that TV stations were paying hundreds of thousands of dollars for less than a decade ago. At the root of this revolution-and let's not be shy, this is a revolution-is the adoption of two parallel technologies. In cameras, it's the move away from the world of analog video, which was epitomized by the VHS format, to digital video in the form of the DV format. In computers, it's the widespread adoption of the IEEE 1394 standard, more popularly known as FireWire (Sony calls it iLink). When you combine the "broadcast" quality output of DV format video with FireWire to move video data from your camera into your computer for editing, and you have the means to make professional looking video for surprisingly little cost.
DV technology is not expensive. You can buy consumer-grade miniDV camcorders for less than $400, and high-quality cameras with excellent video and professional audio capabilities are available in the $2000 range. So what should you look for in a camera and what does that extra thousand dollars get you in higher-end camcorders?
It may seem odd to say this in a story about Cameras, but it's absolutely true: The most important part of the camera is its audio section. Really, I'm not kidding. There's a crusty old broadcasting adage that goes "Television without pictures is radio, but television without audio is . . . " and you can fill in the expletive-deleted blank. As wonderful as the visual aspect of television can be, it only conveys a portion of the message. Audio is essential to communication, and intelligible audio is essential to video.
One of the first things left off sub-$1000 DV camcorders is external audio inputs. If you're tasked with buying a video camera for distance learning applications or for the local public access TV studio that happens to reside at your school, eliminate from consideration any camcorder that doesn't have an external audio input. You'll be stuck with having to live with the audio provided by the on-camera microphone unless you can afford to shoot "double system," that is recording audio with both the on-camera mic and with a completely separate audio recording rig, a subject we'll cover in a future issue.
Of course, some sub-$1000 DV cameras do have external audio inputs, but they utilitze 1/8-inch miniplug connectors. Aside from being incredibly fragile, miniplugs don't match up with most external microphones, because those mics use XLR plugs (see Hall Davidson's "Making Connections" on page 18). Luckily, audio adapters are available that allow you to use good microphones with low-cost cameras. We'll get to more on that subject in a second.
Other things to look for in a camera are:
Fold-out LCD monitors-while using them outdoors can be a challenge because sunlight turns their display into a washed out mess, LCD monitors are really useful when a camera is mounted on a tripod. They also make reviewing tape more convenient than having to plug your camera into a TV set to see your footage.
Top-loading tape drives-a couple of things to watch out for regarding the location of the tape drive and loading mechanism. First, some cameras put the tape drive too close to the on-camera mic, which can make using that mic problematic, as it will pick up too much motor noise. Second, some tape loading mechanisms are positioned so that the shooter's cheek rests against the loading door, which in the long term can cause alignment problems. And finally, some otherwise fine cameras have tape-loading mechanisms whose door opens at the bottom of the camera. Not such a bad thing, unless you have your camera mounted on a tripod. To change tape, you have to dismount the camera.
Three chips-"chips," aka CCDs, are the imaging devices in video cameras. Sub-$1000 cameras use a single CCD to gather red, green, and blue image components. Three-chip cameras use separate CCDs for each. This shouldn't be a deal-breaker, but generally three chips are better than one.
DV versus Digital8-To extend the lifespan of the analog Hi8 format, Sony has released a line of camcorders that record the DV signal onto a Hi8 cassette. The recording quality is identical to that of miniDV, but the cameras are bulkier. Don't invest in Digital8 unless you have a closet full of Hi8 tapes you don't want to go to waste.
Consumer cameras come loaded with all sorts of effects, including all manner of digital effects, sepia tone, video mirroring, and digital zoom. I strongly advise not using any of these hideous things. If you record your footage clean (that is, sans special in-camera effects), you can add whatever effects you want at the editing stage. If you don't like what you've done, you'll still have a good clean master shot to go back to when you (inevitably) change your mind. If you add effects when you shoot, you're stuck with them forever.
Sub-$1000 cameras to consider include: Sony DCR-TRV33, Canon Optura 200MC, Canon ZR60, and Panasonic PV-DV73. Single-chip cameras with external miniplug audio inputs
If your camera budget can stretch over $2000: Canon GL2, JVC GY-DV300U, Sony VX2000 and Sony DSR-PDX10. Three-chip cameras with excellent picture quality; the PDX10 has professional audio inputs as standard equipment
If you can spend over $4000: Panasonic AG-DVX100, Sony DSR-PD150, the Canon XL1S, the JVC GY-DV5000, and the Panasonic AG-DVC200. Very high quality pictures, each has its own special features
One more note: Camera models change at a lightning pace-what's hot today can be remaindered tomorrow. As long as it's new in the box, don't feel bad about buying last year's model and saving a couple hundred bucks. On the other hand, used cameras aren't often a great deal, mainly because you have no idea how much a particular camera has been used (the more hours of use on a camera's heads, the less life it's got left in it) or how it was treated. Avoid the temptation to buy used cameras.
Okay, so you took my advice and bought a camera that has an external audio input or you picked up a handy audio adapter. What are you going to plug into those inputs? I'll split this section in half-mics with 1/8-inch miniplugs and the professional mics that will jack into an adaptor.
Miniplug mikes are generally less expensive-and deliver lower performance-than pro mics, but that doesn't mean they're all bad. One quite capable miniplug mic is the Sennheiser MKE-300 small shotgun (around $170 street price). A big bonus is the built-in hotshoe attachment point, so it will slide right on top of almost any small camcorder.
Low-priced lavaliere (lapel) mics are widely available. Radio Shack sells one for $25, and while its 3-foot cable isn't nearly long enough, with an extension cord and a reasonable amount of care it'll do the job. Others are available from Sony, Azden, AKG, and more, with many models under $75.
Bargain miniplug handheld mics are also available just about everywhere, priced in the $10- $25 range. Again, they aren't going to get you to Carnegie Hall, and their construction can be fairly lightweight, but with a little care they'll get the job done.
If you decide to bite the bullet and do audio the professional way, you'll need an adaptor box. BeachTek, Studio1, and others sell them for about $175-$200 each. These adapters allow you to use professional mics that use the much more robust XLR connector , and let you record two discrete audio channels instead of one. XLR audio (aka balanced audio) connections are much cleaner and quieter than unbalanced miniplug connections, plus it's easier to buy or build really long cables. A low-cost professional shotgun mic can cost from $150 to $450, with the Azden SGM-X1 at the low end of that range and the pro-standard Sennheiser K6/K66 at the high end.
If your kids are going to do "man-on-the-street" interviews, they'll need a handheld microphone. If you opt for XLR audio inputs, they'll be able to use a mic such as the bulletproof ElectroVoice EV635A ($100). It's affectionately known as "The Hammer," and is almost tough enough to be used as one. It's just about student-proof, and sounds good too.
Professional lavalieres are also more expensive than miniplug mics, but are more than worth it for their audio quality and rugged construction. Pro lavs are available from Shure, Sony, ElectroVoice, Audio Technica, and others for less than $200 each.
What about wireless microphones? Wireless mics, while undoubtedly one of the most useful tools ever invented for video production, have little use in the student setting. Why? Three reasons:
- Good wireless mics and the requisite transmitter/receiver rig are relatively expensive.
- Wireless mics represent a single point of failure-so many little things that can go wrong with them that can doom a production.
- Most sub-$2000 cameras are so small there's no place to mount the wireless receiver module on them, and if you can't do that, you've given up the largest part of the wireless advantage.
If you feel you must have a wireless, reasonably good, low-cost setups are available from Sony, Sennheiser, Azden, Samson, and a few others. Expect to pay from $450 to well over $2000 for the really good ones.
Finally, one more word of advice: Set a good example. Never record audio without monitoring with headphones, and don't let your kids do it either. Good headphones can be had for as little as $50, and even a pair of earbuds (Walkman headphones) are much better than nothing.
A camera without a tripod is like a car without wheels-it might run, but it isn't going to work very well for very long. Kids are inundated with fast-cut, MTV-style imagery, so you might face an uphill battle to get them to use a tripod. But even their skateboard videos will benefit from putting the camera on a tripod-watching jittery video can be unpleasant, and Web compression codecs have a more difficult time with jitter vision imagery, too.
The tripods you see TV crews hauling around can easily cost $5000 and up. Luckily, you don't have to spend a tenth of that. If you're not moving the camera, you might be able to live with a cheap still camera tripod, but for any video in which you'll need to pan or tilt the camera, look for a tripod with a fluid head. A fluid head tripod uses a series of valves to regulate oil, which is contained in the head to add tilt and pan drag. (Believe it or not, a tripod that's too loose is much worse than one that is too tight-it's impossible to hold a camera steady on a sloppy tripod head.) In this arena, you are going to see the name Bogen/Manfrotto a lot. They make a huge selection of both still photography and video tripods-and do not confuse the two. Video tripods are designed to pan and tilt smoothly, and to lock down tight when necessary; still tripods are designed to be locked in one spot. A still tripod does not make a good video tripod. A usable Bogen video tripod setup will cost around $300. Other tripod vendors include Vinton, Cartoni, Sachtler, Gitzo, Miller, Matthews, and more.
A big area of economization in consumer-grade DV cameras is the lens. While most cameras will let you focus & zoom fairly well, the manufacturers usually err on the side of giving a lot of zoom range and ignoring the wide end of the lens. You end up with a really narrow field-of-view, even zoomed all the way out. Videos need the "wide shot" to effectively set the stage and establish a point of reference in the viewer's mind. You can't always back up far enough to do that, so it's a good thing that several companies sell wide-angle adapters for cameras. Such adapters vary in the amount of "widening" they do, and at the ultra-wide end they can look disturbingly distorted, but a good medium-wide adapter can do wonders. Century, Kenko, Canon, Sony, and others offer wide-angle adapters that range from $25 up to about $400.
Another must-have accessory is a good, padded camera bag. It should be big enough to hold the camera, the AC adapter/battery charger and batteries, your microphone(s) and audio adapter, and headphones. To skimp here is to consign your camera to an early trip to the repair shop, if not the dumpster. Decent bags from Case Logic and others cost $25-$50.
There are two secret ingredients to making great looking video: craft and lighting. And when it comes to lighting, we're living in a golden age, because while cameras have gotten more compact, they have also gotten more light sensitive. This means it's no longer necessary to tote around thousands of watts of light to get a great image; lighting is now much more of a surgical pursuit.
A few years ago I wrote an article for DV called "Lighting On The Cheap." It showed some easy and inexpensive ways to use lumberyard lights and hardware to make usable, if inelegant, lights for video production. While I stand by that article (you can read it at DV.com), it's important to point out professionals use pro lighting gear for good reasons: It's purpose-built, it's (usually) really sturdy, and you get a lot of light out of small packages. It's also not cheap; a four-light Lowel kit costs about $1300.
You'll see articles claiming "the best light is natural light," and that's half-true. Natural light, when augmented by well-placed highlights, can create a great looking image without breaking the bank. See John Jackman's story on page 22 for more real-world lighting tips and tricks.
While doing an interview for "Teaching Through Technology," I heard a tech-ed teacher at a small northern Wisconsin district say the smartest thing: "Don't feel that you have to have all the answers." Chances are very good that there is a group of kids in your school that's been messing around with computers and video cameras since they were tots, and have skills most of us can only aspire to. Recruit them! Tap their knowledge, have them mentor other less-skilled students, and give them greater responsibility as they earn it. Who knows-you may be creating the next wave of tech-ed teachers to carry forth your message in the decades to come.
Bruce A. Johnson has worked in broadcast television for over 20 years. You can reach him in the Cameras forum on DV.com.
Care and Feeding Tip
Early in the history of DV camcorders, power users became concerned that mixing brands of videotape could be harmful to a camcorder's heads. Why? The theory was that the lubricants used by different manufacturers were incompatible, and when mixed they turned to goo and gunked up the camera's heads. There's some disagreement over whether this was ever the case, but most agree the solution is to either clean your heads regularly, or to stick with one brand of tape for the life of your camera and to clean your heads regularly.
8mm. A video format that improved upon VHS, but not by much, quality-wise.
Aspect ratio. The ratio of length to height in a video image. Conventional TV has an aspect ratio of 4:3, which looks like a slight rectangle. Widescreen images (often seen on DVDs) have a 16:9 aspect ratio.
CCD (charge-coupled device). The official name of the imaging chips used in all video cameras today. CCDs replaced the imaging tube, and made small cameras possible.
Digital Zoom. In contrast to "optical zoom," which moves the image closer by adjusting optics (the camera's lens), digital zoom increases the image size by electronically zooming in on the centermost pixels, making them much more coarse and mosaic-like.
DV (digital video). A catch-all term. In cameras, it refers to a video format. Tip: always record DV tapes in SP mode. Recording in EP mode has been known to produce horrible blocky artifacts.
DVCAM. Sony professional DV format. DVCAM tapes come in mini (the same as miniDV tapes) and a slightly larger size. Note: DVCAM uses a wider track width, so while it's possible to put a miniDV tape with DVCAM-format material recorded on it in a DV-format camera, playback of DVCAM format material won't work due to the different in track size.
DVCPRO. Panasonic's proprietary version of DV, only seen on professional news cameras. Don't confuse it with DV or DVCAM.
FireWire. Apple's name for a transfer protocol used to link up digital video cameras (or other peripherals) to computers. Called iLink by Sony, and officially known as IEEE 1394. A new, faster version, called IEEE 1394b, is backwardly compatible with the old version and has just started to hit the market.
Frame rate. The number of video frames shot per second. Television in North America runs at 29.97 interlaced frames per second. In Europe the standard frame rate is 24.97 frames per second. Film typically runs at 24 progressive frames per second.
Hi8. An enhanced version of 8mm (see 8mm), that uses signal processing to achieve better color.
Interlace. A method of capturing and displaying video in which each video frame consists of two fields, referred to as upper and lower. As each frame is scanned on a display such as a television screen, first one field then the other is shown. The second field consists of scan lines that fall in between the first field's scan lines, hence the term "interlaced." The technique makes fast motion appear smoother and reduces flicker. The opposite of interlace is prograssive scan, in which each line of video is scanned onto the display in successive order.
Lavaliere mic. The "tie-clip" microphones you'll see worn by television newscasters.
Logging. The act of making an accessible record of content of a tape, essential to keeping track of what you have recorded on which tape.
MiniDV. A tape size, not a recording format. Both DV and DVCAM can be recorded to a miniDV tape. (The other tape size is called "standard," and is almost always used in decks, not cameras, with a few exceptions.) A miniDV tape at standard speed can record either 63 or 84 minutes, and is smaller than 2 x 1 x 3/8-inches.
Monochrome. Geek-speak for black and white.
PCM (pulse code modulation) audio. The format every DV camera records audio.
Progressive scan. A technique that records the entire video frame at one time, as opposed to the interlaced recording format of conventional television that splits the frame into two alternate "fields" that are then woven together during broadcast. Progressive scan gives a somewhat more film-like look to a video production. Not all DV cameras have this feature.
Shotgun mic. A directional microphone, often mounted on the camera. Shotgun mics reject noise from outside a predetermined cone.
S-VHS (super-VHS). A popular format at public access TV stations in the 90s, S-VHS handles saturated colors better than VHS.
VHS (video home system). The analog video format of the video tapes you rent for home viewing. You'll likely be playing video back on VHS for years to come, but avoid it as a production format if you can.
Audio Technica www.audio-technica.com
Century Optics www.centuryoptics.com
Radio Shack www.radioshack.com
Sony www.sonystyle.com; www.sony.com/professional
The Human Element
Before going off and spending money on digital video equipment, a word about the videographer: Everyone wants the latest and greatest gear, but the skill of the person behind the camera determines whether the video is worth watching more than the quality of the equipment. Communication and storytelling, after all, is what it's all about. That said, I'd much rather look at video shot with a miniDV camera than on an old VHS camera.
Different types of stories require different styles of videography. Compare the evening news with a PBS or History Channel documentary and a feature film. Aside from purely visual stylistic differences you see between news footage and the highly staged, unreality of films, the visual vocabulary of news, documentaries, and feature films differs in other ways. The video you see on the evening news tends to be very utilitarian, with just enough video to fill the 30-90 seconds allotted to the story. Documentaries can use pictures in a more leisurely fashion, taking time to tell stories with more depth. Feature films use pictures in a manner that serves a script written in advance of filming and so can be customized to suit the style of storytelling.
In all of these examples, the basic building blocks are the same-wide, medium, and closeup shots, pans (movement from left to right or vice versa around an axis), tilts (movement up and down around an axis), zooms, trucks (moving the entire camera horizontally), and dollys (moving the entire camera forward and back). Of all these, only pans, tilts, and zooms are used outside filmmaking. And even these should be employed sparingly at best. Shooting "handheld" is terribly popular as well, but this style of shooting should be reserved for use only when necessary-you may recall stories of audiences getting motion sickness watching The Blair Witch Project, a common side effect of shooting handheld and projecting the results on a screen large enough to fill someone's field of view.
My favorite rule of thumb in videography is, "The wide shot is the most important shot." It's critical to remember a television set is really a very narrow window on a much larger world. You are creating a three-dimensional map in the viewer's mind of a scene they can really only imagine. Every subsequent shot you choose has to reinforce that image, or the viewer will start to think, "Wait! That ain't right." As soon as that happens, the viewers stop thinking about the message, and you've lost them. Consistency is the key, and videography must be in service of the message. Otherwise, as Edward R. Murrow said, television is "merely lights and wires in a box."
Read other articles from the July Issue