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Welcome
to Swift's Cam Glossary
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White Balance
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White Balance is the control that adjusts the camcorder's color
sensitivity to match the prevailing color of
white outdoor light, yellower indoor light, or (sometimes) greenish
fluorescent light. On most camcorders,
white balance may be set either automatically or manually. On some
cameras, you can set white balance to
closely match the exact light in which you're shooting. White balance
may be set "incorrectly" on purpose to achieve special effects. Shooting
outdoors with the indoor setting produces bluish "moonlight" results. Shooting
indoors with the outdoor setting can achieve a romantic, "candle light"
orange cast.
Indoor (incandescent) white balance
Indoor (incandescent) white balance is the camcorder's color sensitivity
setting that matches the warmer cast of Tungsten-halogen lights (so-called
"Quartz" movie lights, work lights, and low-voltage track lights).Household
light bulbs use the same setting, though they are slightly warmer.
Outdoor (natural) white balance
Outdoor (natural) white balance is the camcorder's color sensitivity setting
that matches the whiter
("cooler") cast of natural daylight. This is an average outdoor setting,
because natural light can range from
warm direct sunshine to cooler open shade to very cool high overcast.
Fluorescent white balance
Fluorescent white balance is the camcorder's color sensitivity setting
that approximates the slightly greenish cast of cool fluorescent light.
If your camcorder lacks this setting (not all models include it) set white
balance for outdoors when shooting in fluorescent light. Even with a fluorescent
light setting, results may be less than perfect because, unlike sunlight
and incandescent light, fluorescent light does not contain all the
colors of the visible spectrum.
Auto white balance
Auto white balance is a white balance setting that instructs the camcorder
to analyze the color cast of the incoming light and set itself for the
most pleasing results. Auto white balance may work in two ways. On
less expensive units, it chooses between preset outdoor and indoor settings.
On more elaborated camcorders, auto white balance fine-tunes itself continuously
to adjust to changing light color.
Manual white balance
Manual white balance is a white balance setting that lets you select the
overall color you prefer. It is useful in three situations: when
shooting in cool fluorescent light, manually set white balance to
outdoors, because the auto white balance control will sometimes produce
unpleasant results. When shooting outdoors, you can achieve a bluish moonlit
night look by setting the manual white balance to indoors and underexposing
just slightly. When shooting indoors, you can produce a warm candle light
or fire light effect by setting the manual white balance to outdoors.
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Iris
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Iris is the control that adjusts the size of the
opening in the lens' iris diaphragm, to govern the amount of light admitted.
Along with the shutter, the iris is the principal component in the camcorder's
exposure control system. The camcorder's sensor forms a good quality image
only when struck by exactly the right amount of light. Video is shot, however,
in widely varying light levels, from candle-lit dining rooms to glaring
snow scenes. To accommodate this range, the chip is designed to create
a good image in relatively low light. As the light grows brighter, the
lens' iris diaphragm gradually closes, so that the amount of light reaching
the chip remains the same. In all consumer camcorders, the iris can be
controlled automatically by the camera's light-sensing circuitry. In better
cameras, it can be adjusted manually as well.
Auto iris
Auto iris, often called "auto
exposure" is a camcorder setting that automatically adjusts the opening
in the lens' iris diaphragm to regulate the amount of light admitted to
the camcorder. Auto exposure systems work well, in general, but they can
be "fooled" by some lighting conditions.
Manual iris
Manual iris, or "manual exposure,"
is a camcorder setting that allows the user to adjust the amount
of light reaching the image-forming sensor. This is useful in compensating
for difficult lighting conditions, such as excessive back light.
Some controls can close the iris diaphragm completely, producing a "fade
out" effect.
Manual iris control is best used
sparingly; even slight changes can dramatically affect exposure.
Backlight compensation
Backlight compensation is a camcorder
control that can improve exposure when dark subjects are shot
against brighter backgrounds, such as the sea or sky. Simple back light
controls increase exposure by a
preset amount. More sophisticated versions can be fine-tuned manually,
while studying the effect in the viewfinder.
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Shutter
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Shutter is an electronic control that governs the
amount of time during which incoming light forms a single
video field. (Each video image, or "frame" consists of two fields.)
Since video is recorded at 60 fields per second (in the NTSC system
-- 50 fields in PAL and SECAM) the normal camcorder shutter speed is 1/60
sec. The word "shutter" is actually a metaphor borrowed from the domain
of film, where still and cine cameras control exposure time by means of
mechanical shutters. Video cameras lack physical shutters. Instead,
they control exposure length by adjusting the amount of time during which
the sensor is allowed to accumulate a charge, before dumping it and starting
another video field.
High shutter speed
High shutter speeds
are camcorder settings designed to improve image quality, sharpen images,
or restrict lens focus. Where normal shutter speed is 1/60 sec. (in NTSC
format; 1/50 sec. in PAL and SECAM) higher speeds usually start at
1/250 sec. and range up to 1/12,000 sec., depending on the camera design
High shutter speed are most commonly used to "freeze" motion in individual
video frames, so that normally blurred action (like a golf
swing) can be more easily seen and analyzed. However, excessively high
shutter speed can produce an unpleasant stroboscopic, "jerky" effect.
Low shutter speed
Low shutter speeds are camcorder
settings designed to capture images in extremely low light, or to create
"smeary" special effects. Where normal shutter speed is 1/60 sec. (in NTSC
format; 1/50 sec. in PAL and SECAM) low shutter speeds may be half
that or even less. Low shutter speeds are not widely found on
consumer cameras, because low-light shooting is more often enabled
by amplifying the signal, and the smear effect can be added by effects
generators, either in the camcorder or in editing.
Programmed iris/shutter
Programmed iris/shutter is a camcorder
control that adjusts both the iris diaphragm and the shutter speed together,
to optimize image quality in different shooting conditions. Though these
combined settings can be achieved manually on some camcorders, the programmed
version allow the videomaker to achieve effects without bothering with
technicalities.
Outdoor programmed setting
Outdoor programmed
setting is a setting in which the shutter speed is moderately increased
in order to reduce the incoming light. In very bright conditions, too much
light can strike the image forming chip, even
when the iris diaphragm is at its smallest setting. The result can
be smeary colors. The outdoor programmed
setting will usually correct this problem.
Sports programmed setting
Sports programmed setting is an
iris/shutter combination in which the shutter speed is substantially increased
and the iris diaphragm opening is widened to compensate. The higher shutter
speed freezes the movement in individual frames, so that athletic form
can be more easily analyzed.
Portrait programmed setting
Portrait programmed
setting is an iris/shutter combination in which the iris is substantially
widened and the shutter speed is increased to compensate. Outdoor portraits
and closeups (such as flower shots) can be marred because the small
lens openings required by bright light keep distracting backgrounds in
sharp focus. Increasing shutter speed enables the opening of the iris until
depth of field (focus) is reduced and the
subject remains sharp while the distracting background is softened.
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Lens
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Lens is the camcorder's image collecting system. Its many pieces of
glass work together to gather the light reflected from camera subjects
and focus it as a coherent image on a single plane -- the plane where
the camcorder's image-sensing chip turns it into an electronic signal.
Most, but not all consumer camcorders are fitted with zoom lenses, whose
rendering of the image size and perspective can be varied over a broad
range.
Lens zoom range
Lens zoom range
is the variation in image size that a camcorder lens affords. All consumer
camcorder zoom lenses vary from wide angle at one extreme to telephoto
at the other. (You "zoom in" to telephoto and "zoom out" to wide angle.)
At wide angle settings apparent depth is increased and the angle of view
is quite broad. At telephoto settings, the angle of view is narrow and
apparent depth is reduced. Distant objects look unnaturally large
and movement toward or away from the camera is minimized.
Motorized zoom lens
Motorized zoom lens is a
zoom activated by a servomotor, controlled, in turn by the camcorder's
zoom buttons or rocker switch. Motorized zoom has the advantage of extreme
smoothness and regularity. On the
other hand, the motor consumes battery power rapidly, and the zooming
speed is too slow for some
applications. More elaborate camcorders may have multi-speed zoom motors.
Manual zoom lens
Manual zoom lens is a zoom
activated by the user, usually through a ring around the lens, equipped
with a short handle. All camcorder zooms are motorized, but only some models
include manual zoom. This feature is essential to sophisticated zoom control.
It can be worked very quickly to create a new composition or focus on a
new subject. It also extends battery life considerably because it uses
no power.
Digital zoom
Digital zoom electronically enlarges
the central portion of the image beyond the limits of the zoom lens' ability
to magnify it. As the zoom ratio increases (20 to 1, 50 to 1, etc.) the
image recorded full-frame on
tape represents a smaller and smaller part of the image formed at the
chip. Since the original image consists
of individual dots ("pixels") enlarging part of it progressively coarsens
the picture, lowering resolution and losing detail.
Macro focus lens setting
Macro focus lens setting
is the focus position for very close work, such as copying photos
or documenting a seashell collection. The macro focus position lets the
camcorder come much closer than usual to the subject matter, for
greater magnification. To find your camcorder's closest position, set
the lens at the longest focal length at which the macro function will work
(some camcorders do this only at the wide angle position). Then, physically
move the camera toward the subject until it comes into sharp focus.
Lens stabilization
Lens stabilization is a
feature that compensates, to some degree, for camera shake. Electronic
stabilization works at the chip level, by recording only a large but incomplete
portion of the total image created by the chip. So when the camera
shakes in one direction, the image portion recorded moves proportionately
in the opposite direction, canceling out the camera movement. Mechanical
lens stabilization,
by contrast, moves the image at the lens, by directing incoming light
through a movable prism. When the image moves off the center axis, the
front element of the prism tilts to re-center it at the chip.
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Focus
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Focus is the adjustment of the camcorder lens to
keep the image (or areas at selected distances within it) sharp in appearance.
When the lens is focused at a certain distance, another distance from some
point
before it to some point beyond it appears acceptably sharp. This distance
is called the "depth of field." Depth of field is affected by three factors:
focal distance, lens focal length, and lens aperture (opening). The
greater the distance, the wider the lens angle, and the smaller the aperture,
the deeper the depth of field.
Focused at infinity in bright sunlight, a camcorder lens at wide angle
may be in focus from the horizon to the front of the lens itself. At its
closest focus, in low light levels, a telephoto lens may be in focus through
only half an inch or less.
Autofocus
Autofocus is the camcorder
feature that focuses the lens automatically, usually by determining the
distance to the subject in the central portion of the image. Though very
convenient for fast shooting, autofocus has many drawbacks. It can be slow
to respond; it can rack back and forth, vainly seeking a subject to focus
on; it can have trouble in low light levels; it can mis-focus when the
center of interest is not in the center of the composition; and it
can change focus when a person or object passes between the subject
and the lens.
Manual Focus
Manual focus is the camcorder
feature that lets the videomaker focus the lens where desired. Though preferable
to autofocus in many ways, manual focus requires frequent adjustment by
the user, a process that takes some practice. When focusing manually on
a scene, always zoom to full telephoto, center the most important
subject, focus on that subject, disable autofocus, and zoom back to your
original composition. This ensures that the important subject will remain
sharp at any zoom setting.
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Record
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Record is the control that enables the camcorder's
record function. Pressing it once begins recording, pressing it again stops
the process. (It's not necessary to hold your finger on the button.)
Record/playback
Record/playback
is a pair of functions intended for use when the camcorder is functioning
as a camera (separate record and play controls are provided for the VCR
function).
Record/review
Record/review (which goes by different
names on different cameras) allows you to play back what you've just shot
in the camcorder's viewfinder, in order to check it. Use caution with this
control: it burns up battery power and it can leave the tape with previously
recorded material at the start point. When this happens, the next
shot recorded will erase part or all of a previous shot.
Record indicator light
Record indicator
light is a tiny red light that tells your subjects that they are being
recorded. To avoid spooking sensitive subjects, you may want to tape over
this indicator light (some camcorder let you switch it off).
Standby
Standby is a battery-saving feature
on some camcorders. If record is not enabled within a certain period (say
five minutes) the standby function powers down all camera activities. Pressing
this button reactivates
the system.
Power on
Power on is the camcorder's main on-off
switch. As long as it is on, the camera is ready to begin recording very
quickly because the viewfinder displays an image, the tape is fully threaded
in the tape transport, etc... At the same time, the camera
uses battery power too, so don't switch the system on until moments before
you're ready to tape.
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Viewfinder
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Viewfinder is the display on which you watch the
image you are taping. With the exception of afew inexpensive point-and-shoot
models, all camcorder have viewfinders that are, in fact, tiny video
monitors. Some are now color monitors, and a few are large lcd screens,
mounted externally so you can view them easily.
Viewfinder contrast
Viewfinder contrast is a control
that adjusts the range between the darkest and lightest areas of the viewfinder
image. Too little contrast makes the picture dull and gray; too much makes
picture highlights burn out to white and shadows block up to black.
Viewfinder Brightness
Viewfinder Brightness is a control
that adjusts the overall brightness of the viewfinder image.
Viewfinder color
Viewfinder color is the set of
controls used to adjust color quality on a color viewfinder. Some models
have separate controls for tint (coolness or warmth) and intensity (color
saturation). To adjust a color viewfinder, reduce color intensity
to obtain a black and white picture, adjust brightness and contrast, increase
color intensity to taste, then adjust the tint control last.
Viewfinder readouts
Viewfinder readouts
are words, numbers, and symbols superimposed over the viewfinder image
to tell you what the camera's doing. Readouts vary tremendously among camcorder
models. Typical readouts include tape counter, white balance setting, battery
power remaining, date and time, zoom position, and area monitored by the
autofocus system. Some readouts appear only when special functions are
enabled. In some models, all viewfinder readouts can be disabled.
Viewfinder diopter adjustment
Viewfinder diopter adjustment
allows videomakers with glasses to shoot without them. The controls are
usually a ring around the viewfinder tube, or a slider below it. To use
a diopter adjustment, focus the lens on a distant scene, then adjust the
diopter until the viewfinder image looks sharpest.
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VCR
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VCR is the set of functions that enables a camcorder
to work just like a table-top video deck. Almost all camcorders will
function either as a recording camera or as a VCR, but not both at once.
Some models use a switch to toggle between camera and VCR mode; others
protect the VCR buttons with a door or slider that incorporates a switch.
When the cover's open, you have a VCR; when it's closed, you have
a camera. VCR record VCR record enables the camcorder to copy from video
sources such as cable of another VCR. To perform simple editing, most videomakers
edit from the camcorder to a desktop VCR, but in many cases, it' better
to dub in the opposite direction, if the camcorder has more advanced editing
features.
VCR play
VCR play acts exactly like the play button on a VCR deck.
VCR pause
VCR pause acts exactly like
the pause button on a VCR deck. When editing to the camcorder, begin each
edit by pausing the deck at the start point of the new shot, then press
record, to place the camcorder in
record/pause mode. To begin actual recording, press pause again
to disable it.
VCR stop
VCR stop acts exactly like the stop button on a VCR deck.
Fast forward & reverse
Fast forward & reverse
act exactly like their counterparts on a VCR deck. Generally, camcorder
visible fast forward and reverse have fewer speeds than the same controls
on a deck.
Video insert
Video insert allows
you to replace a length of picture on your edited tape without disturbing
the sound. This feature is not available on those 8mm units whose sound
tracks are co-mingled ("multiplexed") with their video recording.
To use video insert, you make an edit as usual, but press this control
instead of the record button.
Audio dub
Audio dub allows
you to replace a length of sound on your edited tape without disturbing
the picture. This feature is not available on those 8mm units whose sound
tracks are co-mingled ("multiplexed") with their video recording.
To use audio dub you make an edit as usual, but press this control instead
of the record button. On stereo VHS format units, you must disable the
stereo playback feature of your deck, or else you will continue to
hear the old sound instead of the new audio dubbed over it.
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