Would you know what to look for when selecting one or more cameras for home
surveillance? As there are a few options to choose from, it stands to reason
that you should have an idea of the possibilities before rushing to place your
order.
A good place to start from is making up your mind as to the purpose of your
surveillance, and the kind of lighting that will be available at the time of
operation. Remember that most of times cameras should be operated
unattended.
We already affirmed elsewhere that the main purpose of a Home Surveillance
System is essentially for deterrence, as it is quite reasonable that a burglar
will stay clear of any object suspected of being able to collect proofs.
Identification of a person committing a crime though may be quite difficult,
if it cannot be restricted to a small group of known subjects.
A different purpose is that of controlling the behavior of caretakers that
need not be positively identified because you know them. In this case a simple
camera is all you need.
Depending upon the amount of light available on the scene you may be
compelled to opt for black and white if illumination is not sufficient to
support color picture taking.
The capability to change orientation or to zoom in, to enlarge the view of
interesting details, is generally too expensive an option to be considered. It
may be useful only if the images are to be examined by an observer in real
time.
A fixed focus camera whose field of view does not change is probably a
satisfactory choice for most of usual applications, provided the general area to
be surveilled is included.
The sensitive element, called sensor or imager, is possibly the heart of the
camera. It is characterized by the technology describing its make-up (that
should not worry the user), and by its physical area.
Video signals can be transmitted either through a coaxial cable (the most
common way) or by radio (wireless). The first option is quite rigid and may
require drilling holes in the wall and fixing the cable at intervals along its
path.
The other option is much easier at installation and when the need arises to
move the emplacement. However radio transmission may be prone to interferences
that can degrade picture quality.
The external shape of the camera is mostly a question of aesthetics and of
personal preference. So called bullet cameras have a straight form pointing
directly to their field of view.
Dome cameras are enclosed in a semi-transparent plastic bowl that may fit
nicely in indoor space. The exact direction the camera is pointing at is hidden
from view, which can be an advantage for surveillance.
To make an informed choice, the interested person should get familiar with
the basic concepts of surveillance technology and should examine critically the
characteristics of the different options.
This examination however should not paralyze the final decision because any
choice, even if not the best, is far better than no selection at all.
