|
 I
can remember my first encounter with a
Web camera (or
webcam, for short). It was in the early 1990s, and the
item in question was perched atop the
computer monitor of a friend's
desktop pc. It looked like a large, white, and evil eyeball. The
video that the webcam picked up was choppy and in grayscale. But I
can still remember how neat I thought that whole thing was.
Times change, and technology gets better. And so has the quality and
variety of uses of webcams. Sure, you can still use a webcam to
watch the cat or
a pot of coffee, or to record silly hijinks. But you can do much
more with one.
 Like
record high-quality videos and and do audio/video conferencing over
the Web.
Like choosing any other peripheral, picking the right webcam
can be tough. This TechTip looks at some of the factors
you should consider when you decide that a webcam is for you.
Why buy a webcam anyway?
A webcam is definitely not for everyone. Let's be honest, unless you
have a compelling reason to buy one chances are that a webcam will
be way off your radar.
That said, there are a number of reasons to want to buy a webcam. As
mentioned a few paragraphs ago, you might want to record
first-person video tutorials. Or, you might be working remotely and
need to video conference with colleagues and clients. Don't
discount the lure of the Web cam for staying in touch with family
and friends grandparents love them. On top of that, many
people are now using them for face-to-face language exchange with
learners and teachers in other countries. There are other reasons
for getting a webcam, but this site is family-friendly so I won't
mention them here
If you need one and have a
desktop computer, then it's pretty much a given they you're
going to get an external camera. But what about the folks who like
to take their computing mobile? A number of
laptop computers and just about every
netbook out there comes with a built-in webcam. While the
quality and resolution are good, they're not great. If need better
resolution, or if you have an older laptop, then you really need an
external webcam.
Resolution, resolution
 That's
usually the first thing that people look for when buying a webcam. A
previous TechTip covering digital cameras talked about
megapixels and how they weren't the most important factor when
choosing a camera. With webcams, on the other hand, the situation is
somewhat different.
While you won't get the resolution that you would with a digital
camera, a good webcam can offer you up to two megapixels of
resolution. About 1.3 megapixels is often enough for most purposes.
Also, consider the screen resolution of the video on your computer's
monitor. The average webcam offers 320 pixels by 240 pixels.
Which is OK, especially when you're working with a small screen on
something like a netbook. With a laptop or desktop PC, you
can do better. Double that, in fact 640 pixels by 480 pixels.
Framing the seconds
Related to resolution is the number of
frames per second that the camera can process and send to your
computer. Obviously, the larger the number of frames that the camera
spits out per second means the better the video quality. Most
webcams can handle between 10 and 30 frames per seconds. Fifteen
frames per second is about average. With a webcam like that, the
video will be a bit choppy, especially if you suddenly move. Some
higher-end webcams can handle up to 120 frames per second. You
probably won't need anything like that. Thirty to 50 frames per
seconds is probably more than enough for most uses.
Lenses and sensors
 The
real world has to get into the webcam somehow. And that's through
the lens and the sensor. Less expensive webcams use plastic lenses
that are fixed. You can't change the focus. Better webcams have
glass lenses which you can focus by twisting the collar around the
lens. Most people can get by with a fixed lens. But if you can
afford it (more on this later), try to get a webcam with a glass
lens. A glass lens does a better job of moving light to the sensor.
The
sensor is, however, the key piece of the camera. It's the
electronics that converts light into a digital image. There are two
types of sensors:
CMOS and
CCD. CMOS sensors are still used in lower-cost webcams (and a
few more expensive ones). CCD sensors (which are older technology)
are regularly used in still
digital cameras. While I've seen little evidence of the
superiority of one sensor over another, some webcam users prefer
models with CCD sensors. But as with a digital camera, you might
want to find a webcam with a sensor that has strong light
sensitivity and
dynamic range. That way you get better video.
The price that's right
Luckily, webcams aren't as expensive as they used to be. You don't
need to shell out hundreds of dollars anymore. If you check out
Geeks.com, for instance, you can find webcams for under $10
(US).
Depending on your needs and your budget, you can get a very good
webcam for between $50 and $80 dollars. If that's too rich for your
blood, or if your needs are modest, then go with a model that costs
between $20 and $30. You won't get the same resolution or video
quality with the lower cost model, though.
Optional extras
 As
with any other gadget, there are a couple nice-to-have features that
you can look for in a webcam if you so desire. The first of these is
built-in audio. That could mean either a built-in microphone or a
combination of a
microphone and a speaker. With the latter, you don't need to
worry about getting a
chat headset or even a separate set of headphones. The
drawback is that sometimes you're going to get feedback. Ouch!
Most people I know get a webcam with a built-in microphone and use
their headset or the earbuds from their
MP3/MP4 players or iPods. You need to attach the webcam to your
computer. So, you may also want find a webcam with a solid stand or
clip. A clip is a must if you want to use the webcam with
your laptop computer.
The need for speed
Something that's often overlooked is the need for a fast
video card. The video card is doing a lot of the work processing
the information that's coming from a webcam into a computer. If your
webcam offers higher resolution and a high number of frames per
second, then your video card will be doing a lot of work.
If you're serious about using a webcam, you might want to consider
upgrading your video card. Look for one with a fast
graphics processor and a lot of memory. If you don't, you run
into a lot of choppy video which is no fun.
Note: An upcoming TechTip will look at video cards.
Wrapping up
A webcam can not only be useful, it can be a lot of fun.
And buying one doesn't need to be a painful chore filled
with obscure jargon and tech talk. When you decide to go shopping,
remember to take into account what you want to do with the webcam
and keep the factors that this TechTip discusses in mind. That way,
you'll be able to get the webcam that's right for you. |
