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WHAT MAKES ONE
CAMERA BETTER THAN ANOTHER?
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Color vs.
Black & White |
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While color has
been a standard feature in televisions for decades, cameras with black and
white output are still made. While we can all agree that in most cases a
color picture looks better than a black and white one, under some conditions
black & white models perform better.
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In general,
black and white cameras have more lines of resolution, which makes the
picture sharper. They also have lower lighting requirement, formally known
as the LUX rating. More about these two items will be discusses later.
Lastly, black & white models are less expensive than color, a big
consideration if you are investing in multiple units.
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Weatherproof
vs. Indoors |
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 We
realize that most of you want a camera to observe the outdoor areas of your
home. In some cases, there are compelling reasons to have a camera covering
your driveway, backyard, or the front of your home. We offer cameras that
can withstand the effects of rain, snow, wind and wide ranges of temperature
changes.
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 In
most cases when you see a "weatherproof" rating it means the camera can
withstand most types of moisture, it does not mean the camera can tolerate
being submersed in water. Weatherproof cameras have special gaskets to keep
the effects of the environment from damaging the camera's pickup element and
electronics. When indoor-only cameras are used outdoors, the camera will
likely fail in two to five years (even if it is mounted under an eve or
soffit.) If you find a camera that you like and it is not rated for outdoor
usage, we have an
Aluminum
Outdoor Housing that the camera can be installed into and be protected
from the weather.
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Wired vs.
Wireless |
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 The
purpose of the camera is to provide a continuous picture to a monitor,
television, or VCR. There has to be a link between the two and that where
you have to plan for wiring. In some cases, it is not practical to run a
cable between the camera and the monitor, so we offer wireless cameras. Let
me make one point here: wired cameras will be more reliable, provide a
better picture, and cost less than comparable wireless models. Wireless
cameras are available in both black & white and color outputs. We have them
in
weatherproof cases and in
concealed
designs. Most of the wireless models will need to be plugged into
electricity near the camera's mounting location. The camera will then
transmit the picture over a radio frequency (433MHz, 900Mhz, or 2.4GHz) to a
receiver that outputs the picture to a monitor or VCR. The distance the
signal can travel is generally between 100 to 300 feet. Disclaimer alert!
When manufactures give you range estimates for wireless devices it's the
ideal conditions for that device. As I like to say, that range figure is
between two hilltops in the middle of Kansas on a sunny day, your 'actual
mileage' will vary. We do have a
Wireless
Audio/Video Transmitter and Receiver System that can take a signal from
a wired camera and send it several hundred feet to a receiver. This kit will
work with nearly all of our cameras.
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Light
Sensitivity |
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I mention
earlier that all cameras come with a rating to indicate how sensitive the
camera is to light. This figure is called the LUX rating. One lux of light
is the amount of light from a candle measured from one meter away. The lower
the lux rating on a camera, the less light it needs to 'see' properly. Most
folks will not be lighting the outside of their homes like a television
studio, so the lux rating on a camera is very important. In general, black &
white cameras will have a lower lux rating than will color models. If the
camera is being used outdoors, like to monitor a backyard pool, a color
model will look great during the day, but come nightfall, it will be totally
back and the picture will be unusable. An equivalent black and white model
will provide a decent picture will only a porch light turned on. Since the
lighting outdoors can vary, we suggests using a black & white camera.
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 Some
of the black and white models have the ability to operate in total darkness.
Black and white cameras have the ability to pickup light that humans can't
see. Some cameras like theses have infrared illuminators built into the
camera:
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Weatherproof
Wireless IR Camera
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MultiCam
Security Television Camera
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2.4 GHz
Wireless B&W Monitor/Camera System
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 The
illuminators will shine out infrared light a few feet (typically 12 feet) so
that in total darkness the area being covered by the camera will appear
fully lighted. The Ir light will not be perceptible to humans and is not
harmful in anyway. This is the same technology used on the dark rides at
theme parks all over the world. We also offer the
Indoor/Outdoor IR Illuminator that will come on automatically when dark
and flood an area up to 40 feet long and 56 degrees wide with invisible Ir
light. Color models are not sensitive to Ir light, so it's best to choose a
black and white model with the Ir Illuminator.
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Resolution |
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Another
important detail to look for in a camera is the resolution. This
specification is given in lines of resolution where the higher the number
the better the picture will be. Most color cameras have a resolution of 330
to 400 lines. One color model,
Color C-Mount
Camera #7682A has digital processing circuitry and high quality CCD
imager that provides a whopping 570 lines of resolution in color. Black and
white models will do a bit better against a comparable color models ranging
from 350 to 470 lines typically.
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Imager
Element |
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When comparing
cameras, you may notice price differences for what appears to be basically
the same thing. What they rarely mention about these toy cameras are the
specifications. When looking at any camera, check for the specification that
lists the imager used. The imager is the device that converts the light into
electrical signals. Much like a microphone converts sounds into electrical
signals, cameras use an imager. Most budget models use inferior CMOS
imagers. The majority of our cameras use the superior CCD imager.
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Even within CCD
imagers, that can be quality differences. The larger the imager, the better
the picture will be. Below are there screen captures from cameras with 1/4",
1/3" and 1/2" CCD imagers.
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Cameras that
have digital signal processing will deliver a better picture than similar
models that lack this DSP feature.
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Lens |
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This is often
an overlooked specification. All the cameras will need a lens to focus the
light onto the CCD imager. Most of our cameras come with a fixed lens. Only
our C-mount cameras, which are designed for commercial installations,
require the purchase of a separate lens. On most of our web pages for
cameras, we not only give you the field of view in the specification table,
but an actual image captured from the camera is on most pages!
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A camera with a
wide-angle lens will pick up a larger area than a narrow model. That is to
say, a 6mm camera lens will pick up less area than a 3mm lens. The area in
the center of the screen will have more detail with the 6mm model, but at
the sacrifice of picking up less area overall. If you need to read a license
plate from a vehicle with your camera, a camera with a narrower lens (higher
mm) will be a better choice. However, if you want to cover the broadest
area, like your front yard and don't care about the details of a visitor or
intruders face, a camera with a wide angle lens (lower mm) will be an ideal
choice. The trade off is that you will be giving up some detail to get a
broader picture.
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For our C-mount
cameras, we have two variable zoom lenses that can be attached. These lenses
are ideal for locations when you not sure how much of an area you will need
to cover. Below are two examples of different lens angles.
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Some of our
cameras are built into inconspicuous devices like clocks, picture frames,
and non-functional smoke detectors. The camera board in these units use a
special kind of lens called a pinhole lens. The camera looks out a
small hole no larger than an eight of an inch. There will be a small
decrease in quality between a pinhole lens camera and a camera with a
conventional lens.
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No discussion
about cameras can be complete without addressing the issue of focus. When we
talk to callers in our Tech Support department about cameras, the question
of what will be in focus frequently comes up. All the cameras with a fixed
lens will have a large depth of field. This basically means that everything
from 12 inches to infinity will be in focus. Point the camera at the moon,
and it will be in focus. If the camera is pointed at your nose from
arms-length, it too will be in focus.
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Where's the
Audio? |
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If you look
through our Cameras Index page, you will notice that most cameras don't have
a built-in microphone. The trend in the industry has been to eliminate the
microphone in cameras.
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Over the last
few years, United States federal laws have been amended or interpreted by
the courts to put limitations on audio 'eavesdropping' devices. It seems
that while you can justifiably point a camera at your front door and see who
is at the door, the camera's microphone may pickup surrounding sounds. Those
people producing the sounds may not be aware that they are being monitored
or recorded. One of our suppliers reported that they were 'visited' by
representatives of the U.S. Department of Justice over this issue. After
this event, they immediately discontinued all cameras with audio. We do have
a few models with audio still for sale.
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Video
surveillance cameras can be an effective way to monitor and record the
activities on your property. Whenever using these devices, be sure to use
good judgment on its placement. Never use a camera in a place where there is
an expectation of privacy. If you have questions on our cameras, email our
Tech Support staff with your questions or browse the camera pages on our
website:
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