Consider the Rodney Dangerfields of the camcorder: the viewfinder, the microphone and the shutter. Because many videomakers pay scant attention to these humble subsystems, they often fail to get the most out of them.

So this month’s Camera Work turns a spotlight on these three essential but underappreciated camera components. We’ll start with the one you notice only when it irritates you: the viewfinder.

Viewfinders

Camcorder viewfinders get little attention because we tend to look through these tiny TV sets rather than at them. Every camcorder comes with a finder built in of course; the type you prefer should influence your camera buying decision. Your choices boil down to: barrel vs. flip-over design; color vs. black and white; and TV tube vs. LCD panel display.

Today most compact camcorders feature viewfinders in hinged barrels. Some full-size VHS models mount the viewfinder in an assembly that rotates on two axes and adjusts for either eye. The advantage of the barrel type is its small size. The disadvantage is that on most cameras the finder hinges only one way: up. That means you can hold the camera at or below eye level, but not above it.

Full-size VHS finders rotate both up and down–and that’s a big advantage. I often hold the camera high above me while looking up into the viewfinder, in order to shoot over the heads of a crowd.

Also, you can often flip the lens of a full-size finder up out of the way and look directly at the monitor within. This can be much less fatiguing to the eye; it also lets you get your head away from the camera, for better control of camera movement. Some compact camcorder viewfinders allow you to do the same thing, by collapsing the diopter lens right against the display.

Nowadays, some cameras boast color LCD viewfinders. In my admittedly subjective opinion, I think these are expensive frills. If color is so important that you need to check it, you should be using an external monitor anyway.

Also, video compositions are built primarily of forms, and a black-and-white viewfinder emphasizes those compositional elements without the distraction of color. On the flip side, sometimes color is the only thing distinguishing a hard-to-find subject from its background.

Another new trend is the built-in color LCD monitor. Mounted on the back or side of the camcorder, the monitor delivers a color image big enough to actually watch. The good news is that LCD finders separate your head completely from the camera. This delivers much greater flexibility in positioning and moving the camera.

The bad news is that sharpness and contrast are not as good as those of tube-type monitors and the image is affected by the light in which you view it. Also, the coarser image on an LCD screen can make critical focusing more difficult. Still, the image quality of the better LCD models is quite acceptable.

So, if small size and light weight are your foremost objectives, go with the barrel-type finder. If versatility and critical viewing are uppermost, choose a flip-over type. And if ease of use and instant playback are your goals, an LCD finder will work fine.

Using Your Finder

Whichever type you choose, you’ll get the most out of your viewfinder if you:

1) Set it up properly; and

2) Pay attention to what it’s telling you.

Most viewfinders have several adjustments. Some let you manage brightness and contrast. Color models add color controls as well. Diopter correction is a crucial feature for videomakers like me who can’t stand to wear glasses while shooting. You can match the diopter adjustment on the lens covering the viewfinder monitor to the eye looking through it, just as you would the adjustable eyepiece on a pair of binoculars. No camcorder viewfinder will give you as true a picture as a full-size monitor, but the more carefully you tune it, the closer you’ll get.

And once you’ve set up your viewfinder, for goodness’ sake, pay attention to what it’s trying to tell you. Every finder shows readouts of information like white balance setting, footage count, battery reserve and so on. Note: this info can vary from model to model.

Time after time, my students return from location with tales of woe: the picture’s all blue; the battery ran out in the middle of a crucial shot; a big, fat date printed over the image and ruined the footage. In every case, the info they needed to avoid disaster was clearly visible in the viewfinder. But the videomakers, intent on watching the action, looked right through it.

External Viewfinders

Like studio camera operators, you can use a stand-alone viewfinder that receives its signal from the camcorder. Add-on LCD monitors are wonderful for shooting events like plays in a theater. (Try pasting your eye to a camcorder finder for two solid hours and you’ll see why.)

But LCD monitors have disadvantages over and above the ones mentioned earlier:

1) Their battery packs drain quickly;

2) Their alternative AC adaptors and cords are clumsy; and

3) They either claim the camcorder’s accessory shoe or else attach with clunky adaptor brackets.

As you can see, I don’t think add-on LCD monitors are yet ready for prime time; but some videomakers love them and swear by them.

The best external viewfinder is a color monitor. Pros use three-to-five-inch AC/DC portable versions with battery packs, but any decent monitor will do the job. Obviously, external monitors limit your mobility; still, for studio work and for applications where composition and lighting control are crucial, they’re essential. Above all, knowing that what you see is what you get does wonders for your confidence.

But stand-alone monitors take us away from the camcorder; so let’s climb back aboard it to look at our next underappreciated subsystem, the microphone.

Camcorder Microphones

Camcorder mikes are why home video is so spectacularly popular. Home movies have been around since the ’20s, of course, but never with sound. It’s the sense of reality, of being there, that makes video more vivid and immediate. And we have live, synchronous sound to thank for that. So let’s tip our hats to the camcorder mike, which initially captures the sound.

Like most microphones, on-camera mikes are at least somewhat directional–that is, they pick up sounds within a pattern of sensitivity. Sounds originating in the main part of the pattern record with the best quality. More peripheral sounds record less well; and sounds coming from outside the pickup pattern record poorly or not at all. (Figure 1 shows patterns of some typical camcorder mikes.)

Simpler camcorders tend to have basic microphones with fairly wide pickup patterns. The advantage of this design: the mike always covers every sound source in the frame, no matter how wide the angle of the shot. A wide pickup pattern also does a better job of capturing the ambient sound so crucial to a sense of realism.

The down side: wide-pattern mikes are unselective. Along with the sound you want, they also sweep up the background noise that you don’t want. This muddies up your audio and degrades sound quality.

To help solve this problem, some camera mikes are switchable. You can set them to a wider pattern to record events like wedding receptions, or switch them to a narrow pattern for jobs like interviews.

Some mikes even zoom automatically; they adjust the angle of their pickup pattern continuously to match the wide or telephoto setting of the camera lens.

An automatic zoom mike sounds great in theory, but has its own inherent limits. For example: a telephoto mike setting works well if you zoom the lens in to capture a distant subject. But if you place the lens in telephoto position to isolate a detail of a close subject, the microphone pattern may be too narrow for optimal recording.

Some camcorder mikes address the close/distant problem differently. Instead of changing pickup pattern, they change sensitivity. To reduce background noise when taping an interview, you select the low sensitivity setting. To pull in sound from a distant subject, set the mike switch to the high setting.

Many of the more sophisticated cameras deliver stereo sound. Their on-camera mikes have two pickup elements with different but overlapping patterns.

The paradox of stereo recording is that this higher quality sound benefits only those less ambitious videomakers who never add music and/or narration in post production. That’s because post-production audio restricts you to the lo-fi monaural track. This doesn’t mean you can’t edit footage and still retain stereo sound; it’s just that you can’t supplement the original camera tracks.

Working With Mikes

If your on-camera mike has switchable pattern or sensitivity settings, by all means use them. The quality improvement you gain will be obvious.

But whatever types of controls you have, you can improve on-camera sound quality by using certain basic techniques.

First, always shoot as close to your subject as possible. Instead of setting the lens to telephoto and standing back, zoom out to wide angle and move in. The closer the mike to the sound source, the better the audio quality. (But don’t use extreme wide-angle settings for interviews. At very close distances, the wide-angle lens exaggerates depth, giving the interviewee a nose like a toucan.)

Next, keep yourself as silent as possible because all camera mikes will pick up the videomaker’s voice. This is great for narrating on the fly; in most other cases the results sound amateurish.

Also, be sensitive to sources of unwanted sounds; aim the camera and its mike away from them. For example: when doing a person-on-the-street interview, position your interviewee so that you can shoot with your back to the street and its traffic noise.

Finally, consider an add-on camera mike. For under $100, you can obtain a shotgun microphone that attaches to the camcorder accessory shoe and plugs into the mike input (which automatically disables the built-in mike). Most of these units feature switchable pickup patterns and deliver noticeably better sound quality.

Keep in mind, however, that supplemental mikes do not come without their own tradeoffs. They preempt the shoe you might want for a camera light and their 3.5 mm mini plugs are easy to jostle loose. Most importantly, they require batteries that can fail in the middle of a shot. When your camera battery goes, you know instantly that you’re out of business; but unless you’re wearing headphones, you won’t know that your shotgun mike went belly up until you play back a tape that goes suddenly, catastrophically silent. (The moral, of course, is always wear headphones.)

To conclude our salute to underappreciated camcorder subsystems let’s dive inside the machine to search for a component that, in fact, we can never find: the shutter.

The Phantom Component

We can’t find the shutter because camcorders don’t have them. The terms “shutter” and “shutter speed” are just analogies borrowed from film photography.

In the domain of film, a camera shutter is a mechanical component that controls how long light can strike the emulsion in a film camera. The shutter speed expresses of that amount of time. A cine camera shutter speed is typically 1/50 second. Still camera speeds range up to 1/2000 sec. or more.

A video camera, by contrast, does not have a physical shutter. Instead of deploying mechanical blades or curtains, a camcorder uses electronics to control how long light can form an image. At the normal setting, the CCD that creates the image completes the process once every 1/60 sec. It operates at this speed because the camcorder must create one video field every 1/60 sec. in order to build a two-field frame at the rate of 30 per second. Thus, the “shutter speed” is the time in which the imaging device reads out each field image.

All this would be purely academic, except for one important thing. In many camcorders, you can change the shutter speed. Instead of shooting at 1/60 sec., you can capture images formed in 1/250, 1/1,000–up to 1/10,000 in some cameras–of a second. (Keep in mind, however, that the camcorder still records just one field in each 1/60 sec. time period, even if that field was captured in only 1/1,000 sec. That’s why a conventional camcorder, unlike a cine camera, cannot record true slow motion.)

What do you achieve by changing the shutter speed? Two big advantages. First, you can sharpen the appearance of fast-moving objects by shooting them at higher speeds. Since an object moves far less in 1/1,000 sec. than it does in 1/60 sec, its image will be much less blurred by motion.

Recently my students videotaped steel balls dropped three stories into a sand pit (to simulate asteroids forming craters, for an astronomy project). At normal shutter speed, the resulting impacts were just messy blurs of flying sand.

But at 1/2,000 sec., each field showed a crisp ring of sand particles, exploding in a complex and elegant pattern. A fast shutter speed will have the same effect on the videotape of a golf swing, for instance.

Be aware, however, that high shutter speeds don’t always provide the intended effect. For example: a passing race car moves exactly the same distance between fields, whether those fields are shot at 1/60 sec. or 1/2,000 sec. So the blur resulting from normal shutter speed can actually smooth the transition from field to field. At fast shutter speeds, by contrast, the sharper individual images can create an unrealistic strobe effect.

The second advantage of increasing shutter speed is that doing so also increases the size of the camera lens opening. Every time you double the speed, you open up the lens by one stop. If the automatic exposure system closes the lens to f22 at normal shutter speed, doubling the speed to 1/125 sec. opens the lens to f16; 1/250 sec drops the stop to f11, and so on. (Remember, the lower the f-stop number, the wider the lens opening.)

Why open the lens? Because doing so reduces the depth of focus. The wider the opening, the shallower the field in which objects are sharp. This is especially useful for throwing backgrounds out of focus in portrait and flower videography.

A Little Respect, Please

So that’s our quick review of underappreciated camcorder subsystems. You can make decent video programs without paying attention to the viewfinder, the microphone and that Phantom of the Camcorder, the shutter.

But the better you understand them, the better you can control them for more professional videomaking.

Videomaker contributing editor Jim Stinson makes industrial videos and teaches courses in professional video production. Send e-mail to 71161, 1722@cserve.com.

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