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Security Camera Styles, Where, When, Why and Which Ones To Use

Security cameras come in several different types and styles with features and specs that can be overwhelming for someone who doesnt hold an electronics engineering degree. We will go through all of the major types of CCTV security cameras, where to use each style, as well as explain some of the basic specs so that you can decide what type of CCTV equipment is right for your security system.

Bullet Cameras

Bullet Cameras are weatherproof and tend to be smaller than other types of security cameras. They come in sizes and shapes ranging from the size of a tube of lipstick to the size of a typical soda can. Bullet Cameras are also called lipstick cameras, tube cameras or missile cameras. If you are looking for nightvision or infrared cameras, you will find the largest selection among bullet cameras.

Dome Cameras

Dome type security cameras are the most popular style of security cameras. They usually have a base with a screw-on dome. The domes are tinted so that it is difficult to tell where they are aiming, this makes them very popular for retail applications. Most domes cameras are plastic, though you can check the armor dome section for vandal-proof domes which tend to be weatherproof with metal bases and polycarbonate sealed domes.

Armor Domes

Armor dome security cameras, or vandal domes, tend to be a little bit bigger than standard domes. They are more rugged in their construction and usually have heavy duty seals which make them weatherproof for outside installation. Most of the higher quality armor domes have a 3 axis gimbal, which allows them to be mounted on a wall as well as a ceiling. Armor domes are available with fixed lenses or adjustable lenses as well as with or without nightvision.

Box Cameras

Box cameras, or professional style security cameras, are the most versatile style of CCTV camera available. They do not usually include a lens or a mount, so you will need to purchase the lens and an indoor mount or outdoor housing separately. They are more complicated than domes or bullets, but box cameras allow for specialty lenses (i.e., for license plate recognition) and generally have more video quality controls than other styles of security cameras.  If you are mounting a box camera outside it will require an outdoor housing.

PTZ Cameras

PTZ cameras or Pan Tilt Zoom cameras are the most complicated style of security camera. These PTZ cameras are generally large dome cameras with motorized and computerized internals allowing for the camera to be controlled from the DVR, remotely or through a PTZ controller. These cameras use RS485 to receive controls and programming, so your DVR may require an RS232 to 485adapter. PTZ security cameras can also be programmed to run patterns. Speeds vary from 10 degrees per second to speed domes which can move in excess of 300 degrees per second.

Hidden Cameras

Hidden security cameras, covert cameras or spy cameras are some of the most popular style of security cameras available. These cameras use pinhole lenses with very tiny lenses and are usually enclosed in some other device that doesn't look like a camera. Motion detectors, sprinkler heads, smoke detectors, wall clocks and custom configurations are common housings for covert security cameras. Some hidden cameras come with built-in microphones as well. Consult your local laws concerning audio surveillance.

Infrared / Nightvision

Infrared cameras or nightvision cameras are extremely popular with our customers. These nightvision security cameras provide clear color images during the day, and black and white images at night.  At night, infrared security cameras glow red and provide the camera with artificial light that can only be seen by the camera. These IR cameras operate even in total darkness. The more LED's a camera has, the farther away it will see at night. Nightvision cameras are available in weatherproof bullet, dome and armor dome styles.

Low Light Cameras

Low light cameras are generally not able to see in total darkness, but are excellent for areas where clear security video is needed 24 hours a day, and there is some lighting available. These cameras, also called Low Lux cameras or Day/Night cameras can use a feature called sense-up to provide color images even in very low light conditions. Cameras with sense-up will sometimes need to be programmed during installation as the light sensitivity and shutter controls are adjusted through On Screen Display (OSD). Low light security cameras are usually available as domes, high-end bullets and box cameras.

Lighting Required

Cameras marked with the lighting required tile require better lighting. These cameras have a lux rating of 0.1 or higher and are generally best for installation in offices or homes where there will generally be better lighting available. (the lower the lux rating is, the better the camera will be able to see in low lighting. Some vendors will call these Day/Night cameras because they have a relatively low lux rating of 0.1lux, however, in our experience, that may be technically true, but far from the low light video quality most people expect.

Indoor

Indoor security cameras do not have any weather sealing. Water and moisture will kill a security camera faster than any other condition, therefore, these cameras should only be installed indoors where they will not see condensation or extreme temperatures. Indoor only security cameras come in dome styles as well as covert and PTZ styles.

Outdoor

Outdoor cameras come in various ratings. Weatherproof ratings begin with "IP" (international protection rating) and end with a number above 54. The higher the number the more weather resistant the camera is. Typically, IP65 is the standard rating, meaning that a camera with an IP65 rating can withstand a blast of direct water. IP67 means a camera is submersible up to 1 meter. Use weatherproof cameras outdoors or where temperature and condensation are an issue, like inside a walk-in cooler or in a workshop with lots of dust.

Outdoor Housing Required

The outdoor housing required category is for our more advanced security camera styles such as box cameras which require a separate housing to be placed outdoors. Housings are available separately in our accessories section and come with or without heaters and blowers for defrosting in the winter and camera cooling in the summer.

Fixed lens

Cameras that are marked with the fixed lens tile come with a fixed, non-adjustable lens. These cameras typically have 3.6mm semi-wide angle lenses providing an image that is 74 degrees wide. The higher the lens number in mm, the tighter the shot will be, and vice versa. Indoor domes with fixed lenses can be adjusted by purchasing separate mini-lenses in our accessories section.

Adjustable lenses

Security cameras with manually adjustable lenses, sometimes called vari-focal or "zoom" lenses allow the user to manually adjust the viewing angle when installing the cameras. These cameras allow the installer to dial in the level of detail they want to see in their shot and are very useful for front door shots or cash register views where detail is very important. The lower the lens number is, the wider the shot will be and vice-versa. Lenses with wider ranges are more versatile and can be adjusted over a wider viewing angle range. These lenses also control Iris openings giving the user the best light level adjustment without having to make any installation changes. Varifocal lenses are available on domes, armor domes and bullet cameras.

Motorized lenses

Security cameras with motorized lenses are usually called zoom cameras or ptz cameras. These cameras can be controlled electronically to zoom in and out in real time. They require RS232 to 485 adapters to control and are nice to have when someone is sitting in from of the DVR and is able to determine the best viewing angle for the situation. Motorized lenses are usually seen on ptz style dome cameras and as an option on box style security cameras.

What exactly is a TVL?

TVL is a resolution rating meaning television lines, the higher the number of TVL a camera has, the higher the picture quality of that camera. Basically the TVL is a count of the number of horizontal lines a camera can reproduce. This measurement started out as a way for the original television broadcaster to claim they were broadcasting in higher resolution than they actually were, but today, it is a useful measure when determining the comparative video quality between two seperate cameras. Today, the industry standard resolution seems to be 420TVL. High resolutions begins around 480TVL, though many cameras are available with resolutions well above that. 540TVL, 600TVL, 650TVL and 700TVL cameras are not uncommon. This is a sliding scale of course. The difference between a 350TVL camera and a 420TVL camera will  be more dramatic than that between a 420 and 480TVL rating. Still, as a general rule, when it comes to TVL, the higher the number, the clearer the picture.

What is Lux,  and why is it important?

Lux is a measure of illuminance, or in other words, a measurement of the amount of light available. The lux rating of a camera tells you how much light is required for that camera to provide a usable image. Keep in mind that the term "usable" is very subjective, and that lux ratings can be "adjusted" by unscrupulous manufacturers and marketers to make it appear they have a better CCTV camera. In general, the lower the lux rating of a given camera, the better that camera will perform at night or in low light conditions. Be wary of comparing lux ratings of cameras from different manufacturers as the lux rating relies on the F-stop at which it was measured, usually seen as 0.1 Lux @ F1.2. This subject requires an entire article to discuss properly, though you should now have enough information to make an informed decision on which product is right for you.

About the Author

Alex Underwood is Director of Product Development at CCTVDynamics. http://www.CCTVDynamics.com is working to make high end security surveillance solutions available to every American who wishes to protect their property, their families and their businesses. We believe a secure home or business doesnt need to break the bank. Check our catalog to explore different styles of security cameras.

 

How does CCTV dome camera differ from a conventional CCTV camera?

the question relates to available features or merits and advantages etc.

The dome cameras are able to pivot 180 degrees or more vertically and can rotate 360 degrees horizontally. This creates a large area the camera is capable of viewing that covers everything below its mount.

The areas under a normal CCTV cameras are a blind spot because of the camera's limited mobility.

Open faced CCTV vandal dome camera with IR lighting and zoom lens from cctv42.co.uk