If you have come this far you surely need to
install a security camera. But
today's market is littered with security cameras, and they all claim to be the
best. But it may be that you buy a security camera and it is not what you
expected. It has happened to me. How can you choose the camera that best suits
your situation?
In a short, simple and clear way I want to explain
how to make a good decision.
To make a good choice you have to take into account
the following points:
·
Understand the different characteristics of a
camera (lens aperture, IR power, image quality, etc.)
·
Know what you are looking for
·
Compare the ones that fit what you need
·
And if you have doubts, ask an expert
If you are looking for the best in surveillance
cameras, surely you are interested in the blog post: What are the best video
surveillance cameras?
Do you need help to correctly install a camera?
Take a look at our guide.
Understanding
the main features
When you search for the word security camera in Google, you will get thousands of options, each
with different specifications. But only a few are the ones that will really fit
what you need. Understanding all these terms can sometimes be a bit
complicated, but that's what I'm here for: to be able to explain it to you.
What is the main thing you should look for and
understand?
·
Differentiate between connection types
·
Recognize video resolution
·
Angle of view of the lens
·
Power night lighting
·
Storage methods
Connection
type
First of all, you must understand that there are
several types of cameras depending on their connection. This is what I mean by
headlines like:
·
Analog camera
·
IP camera
·
WiFi camera
Analog
cameras
Analog cameras refer to those that go to a video
recorder (DVR) and do not have the IP or WiFi communication protocol. For
operation they must be connected by cable to the DVR. The analog signal only
accepts a maximum quality of 720p, so they have already been converted to
digital if a higher quality is wanted. The communication protocol can vary, but
it is usually TVI, AHD or CVI.
So in order to choose a camera that goes by cable
to a DVR, you have to assess whether the communication protocols are the same
or compatible. That is, if you have a CVI protocol recorder, you must buy a camera
that uses CVI as well. Many of the “ white label” cameras use different
protocols to fit most recorders, so we won't have much of a problem finding one
that fits.
IP or WiFi
cameras
A WiFi camera is necessarily an IP camera; but an
IP does not have to be a WiFi.
IP cameras are all those that are connected
directly to the network, either by Ethernet cable or by WiFi. Be careful, not
necessarily to the Internet, but the installation can also be carried out
through a local network. But generally they will be connected to the Internet
to be able to see them from anywhere in the world.
To access them and their configuration can usually
be accessed through a web browser, entering the IP address of the same. Others
accept the configuration from a smartphone application, prepared for the user
with basic knowledge.
These IP cameras, whether they are WiFi or not, can
also be connected to a DVR or NVR recorder, since many of them accept IP
cameras in their configuration. For example, there are VCRs that have 4 channels
for analog cameras and 2 for IP cameras (4 + 2 DVR). To do this, take into
account the communication protocol: the most common could be On vif , but we
can also find others such as FTP, NAS, NFS or RTSP . In either case, the
camcorder and the VCR must be compatible.
Video
resolution
The second thing that will come out in almost all
the ads will be the image quality. It should be noted that they can be
expressed in different ways, but in many cases it is the same. For IP cameras,
we started using expressions and resolutions in megabytes, since analog ones
work with lines. But when going from analog to digital cameras we can find the
same expressions in both.
The best quality is currently 8K, and the worst is
one of… 450 lines? (I don't even know if it still exists). In any case, I leave
you a table below with the image resolutions and the nomenclatures used.
NOMENCLATURES
USED RESOLUTIONS
QCIF 176
x 120
CIF 352
x 240
4CIF 640
x 480
D1 720
x 480
720P / 1 MP / HD 1280 x 720
1.3 MP 1280
x 1024
1080P / 2.0 MP / FULL HD 1920 x 1080
2 MP 1600
x 1200
3 MP 2048
x 1536
5 MP 2592
x 1944
4K / 8 MP 3840 x 2160
10 MP 3648
x 2752
12 MP 4000
x 3000
8K / UHD / 33 MP 7680 x 4320
Vision angle
Third, you have to look at something very
important: the angle of view. What is the field of view? It is the entire area
that the camera lens has access to and therefore will reflect on the image.
This is extremely important. Depending on what we want to record, we will be
interested in a very wide or narrower angle of view.
Examples:
Surveillance camera in a factory corridor, which is
2 meters wide and 20 meters long. In this case, it is not interesting to have a
wide-angle camera, since we would be seeing more walls on the sides than
corridor. It is more interesting to have a camera with a more closed angle, for
example 45º.
I want to security camera installation in Chicago
of my chalet, which has great distances in width and length. As I want to cover
as much as possible with a single device, I will have to choose the one with
the greatest angle, 160º would be enough in this case.
To get an idea of how much each graduation is, I
usually use my own eyes and sometimes my arms. Human vision has an approximate
angle of 160º, that is, what you can see without moving your eyes including the
periphery. If you need to calculate a 90º angle, use your arms: open them at a
right angle using your chest as the vertex.
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