Dome Cameras for CCTV

Embed Size (px)

Citation preview

  • 8/6/2019 Dome Cameras for CCTV

    1/12

    Dome Cameras for CCTV & Surveillance

    Dome Cameras are typically used indoors, however outdoor use is not out of the quesiton. Many

    dome cameras are protected from vandalism by being enclosed in a vandal-proof shell. Retail

    stores, small businesses, and hospitals are the biggest consumers of dome cameras.

    Lens Focal Length* Terminology Typical PhotographyLess than 21 mm Extreme Wide Angle Architecture

    21-35 mm Wide Angle Landscape35-70 mm Normal Street & Documentary

    70-135 mm Medium Telephoto Portraiture135-300+ mm Telephoto Sports, Bird & Wildlife

    Dome Camera Uses

    Dome cameras generally mount from the roof. Dome cameras are considerably more

    eye-pleasing than c-mount security cameras or bullet security cameras, however their

    protective domes keep them from seeing as far. A smoke-colored shell will keep yourvisitor's from knowing where the camera is pointed, but can further reduce the distance

    it can record.

    Despite being designed for indoor use and having less range, dome cameras are oftenused outdoors because of their vandal proof casing. A few dome cameras even haveinfrared lights for recording in zero light.

    Don't use a Dome Camera If...

    Don't use a dome camera if you don't have infrared lights and plan on recording in an

    area without any light.Don't use an infrared dome camera towards a glass window or reflective surfaces.

    Don't use a Dome Camera if you want to record an area farther than 100 feet away and60 ft is advised for most dome cameras.

  • 8/6/2019 Dome Cameras for CCTV

    2/12

    Network camera types

    Network cameras can be classified in terms of whether they are designed for indoor useonly or for indoor and outdoor use. Outdoor network cameras often have an auto iris

    lens to regulate the amount of light the image sensor is exposed to. An outdoor camerawill also require an external, protective housing unless the camera design already

    incorporates a protective enclosure. Housings are also available for indoor cameras thatrequire protection from harsh environments such as dust and humidity, and from

    vandalism or tampering. In some camera designs, vandal and tamper-proof features arealready built-in and no external housing is required.

    Network cameras, whether for indoor or outdoor use, can be further categorized intofixed, fixed dome, PTZ, and PTZ dome network cameras.

    Fixed network cameras

    A fixed network camera, which may come with a fixed or varifocal lens, is a camerathat has a fixed field of view (normal/telephoto/wide-angle) once it is mounted. A fixed

    camera is the traditional camera type where the camera and the direction in which it ispointing are clearly visible. This type of camera represents the best choice in

    applications where it is advantageous to make the camera very visible. A fixed camerausually enables its lens to be changed. Fixed cameras can be installed in housings

    designed for indoor or outdoor installation. See fixed cameras product range.

    Fixed network cameras including wireless and megapixel versions.

  • 8/6/2019 Dome Cameras for CCTV

    3/12

    Fixed dome network cameras

    A fixed dome network camera, also called a mini dome, essentially involves a fixed

    camera that is pre-installed in a small dome housing. The camera can be directed topoint in any direction. Its main benefit lies in its discreet, non-obtrusive design, as wellas in the fact that it is hard to see in which direction the camera is pointing. The camera

    is also tamper resistant.

    One of the limitations of a fixed dome camera is that it rarely comes with an

    exchangeable lens, and even if it is exchangeable, the choice of lenses is limited by thespace inside the dome housing. To compensate for this, a varifocal lens is often

    provided to enable the cameras field of view to be adjusted.

    Axis fixed dome cameras are designed with different types of enclosures such as

    vandal-resistant and/or IP66-rated for outdoor installations. No external housing isrequired. The mounting of such a camera is usually on a wall or ceiling. See fixeddomes product range.

    Fixed dome network cameras. From left to right: AXIS 209FD and AXIS 216FD (also

    available in ruggedized and megapixel versions), AXIS P3301 and AXIS 225FD.

    PTZ cameras and PTZ dome cameras

    A PTZ camera or a PTZ dome camera can manually or automatically pan, tilt and zoom

    in and out of an area or object. All PTZ commands are sent over the same networkcable as for video transmission; no RS-485 wires need to be installed as is the case with

    an analog PTZ camera.

    Some of the features that can be incorporated in a PTZ camera or a PTZ dome camera

    include:

    y Electronic image stabilization (EIS). In outdoor installations, PTZ dome cameras withzoom factors above 20x are sensitive to vibrations and motion caused by traffic or

    wind. EIS helps reduce the affects of vibration in a video. In addition to getting more

    useful video, EIS will reduce the file size of the compressed image, thereby saving

  • 8/6/2019 Dome Cameras for CCTV

    4/12

    valuable storage space.

    y Privacy masking. Privacy masking, which allows certain areas of a scene to be blockedor masked from viewing and recording, can be made available in various network

    video products. In a PTZ camera or PTZ dome camera, the functionality has the ability

    to maintain the privacy masking even as the cameras field of view changes since the

    masking moves with the coordinate system.

    With built-in privacy masking (gray rectangle in image), the camera can guarantee privacy

    for areas that should not be covered by a surveillance application.

    y Preset positions. Many PTZ cameras and PTZ dome cameras enable a number ofpreset positions, normally between 20 and 100, to be programmed. Once the preset

    positions have been set in the camera, it is very quick for the operator to go from one

    position to the next.

    y E-flip. When a PTZ dome camera is mounted on a ceiling and is used to follow aperson in, for example, a retail store, there will be situations when a person will pass

    just under the camera. When following through on the person, images would be seen

    upside down without the E-flip functionality. E-flip electronically rotates images 180

    degrees in such cases. It is performed automatically and will not be noticed by an

    operator.

  • 8/6/2019 Dome Cameras for CCTV

    5/12

    y Auto-flip. PTZ cameras, unlike PTZ dome cameras, do not normally have a full 360-degree continuous pan due to a mechanical stop that prevents the cameras from

    making a continuous circular movement. However, with the Auto-flip functionality, a

    PTZ network camera can instantly flip the camera head 180 degrees and continue to

    pan beyond its zero point. The camera can then continue to follow a passing person or

    object in any direction.

    y Auto-tracking. Auto-tracking is an intelligent video functionality that willautomatically detect a moving person or vehicle and follow it within the cameras

    area of coverage. Autotracking is particularly beneficial in unmanned video

    surveillance situations where the occasional presence of people or vehicles requires

    special attention. The functionality cuts down substantially the cost of a surveillance

    system since fewer cameras are needed to cover a scene. It also increases the

    effectiveness of the solution since it allows a PTZ camera or PTZ dome camera to

    record areas of a scene with activity.

    Although PTZ cameras and PTZ dome cameras may share similar functionalities, there

    are differences between them:

    y PTZ network cameras do not have a full 360-degree continuous pan due to amechanical stop. It means that the camera cannot follow a person walking

    continuously in a full circle around the camera. Exceptions are PTZ cameras that have

    the Auto-flip functionality; for example, AXIS 215 PTZ Network Camera.

    y PTZ network cameras are not made for continuous automatic operation or so-calledguard tours where the camera automatically moves from one preset position to the

    next.

    Mechanical PTZ network cameras

    Mechanical PTZ cameras are mainly used indoors and in applications where an

    operator is employed. The optical zoom on PTZ cameras typically ranges from 10x to

    26x. A PTZ camera can be mounted on a ceiling or wall.

    PTZ network cameras. From left to right: AXIS 212 PTZ-V (non-mechanical), AXIS 213 PTZ,

    AXIS 214 PTZ and AXIS 215 PTZ.

  • 8/6/2019 Dome Cameras for CCTV

    6/12

    Non-mechanical PTZ network cameras

    A non-mechanical PTZ network camera, such as the AXIS 212 PTZ and its vandal-

    resistant version (seen above), offers instant pan, tilt, zoom capabilities with no moving

    parts, so there is no wear and tear. Using a wide-angle lens, it offers a wider field ofview than a mechanical PTZ network camera.

    Images from a non-mechanical PTZ network camera. At left, a 140-degree overview image

    in VGA resolution; at right, image when making a 3x zoom.

    A non-mechanical PTZ camera uses a megapixel image sensor and allows an operator

    to instantly zoom in on any part of a scene without any loss in image resolution. This isachieved by presenting an overview image in VGA resolution (640x480 pixels) even

    though the camera captures a much higher resolution image. When the camera isinstructed to zoom in on any part of the overview image, the camera uses the original

    megapixel resolution to provide a full 1:1 ratio in VGA resolution. The resulting close-up image offers good details with maintained sharpness. With a normaldigital zoom,

    the zoomed-in image often loses detail and sharpness. A non-mechanical PTZ camerais ideal for discreet, wall-mounted installations. See PTZ cameras product range.

    PTZ dome network cameras

    PTZ dome network cameras can cover a wide area by enabling greater flexibility inpan, tilt and zoom functions. They enable a 360-degree, continuous pan, and a tilt of

    usually 180 degrees. PTZ dome cameras are ideal for use in discreet installations due totheir design, mounting (particularly in drop-ceiling mounts), and difficulty in seeing the

    cameras viewing angle (dome coverings can be clear or smoked).

    A PTZ dome network camera also provides mechanical robustness for continuousoperation in guard tour mode, whereby the camera automatically moves from one

    preset position to the next in a pre-determined order or at random. Normally up to 20guard tours can be set up and activated during different times of the day. In guard tour

  • 8/6/2019 Dome Cameras for CCTV

    7/12

    mode, one PTZ dome network camera can cover an area where 10 fixed networkcameras would be needed. The main drawback is that only one location can be

    monitored at any given time, leaving the other nine positions unmonitored.

    The optical zoom of a PTZ dome typically ranges between 10x and 35x. A PTZ dome

    is often used in situations where an operator is employed. This type of camera isusually mounted on a ceiling if used indoors, or on a pole or wall of a building in

    outdoor installations. See PTZ dome product range.

    PTZ dome network cameras. From left to right: AXIS 231D+, AXIS 232D+, AXIS 233D.

    Next topic: Day & Night network cameras

    Day & Night network cameras

    Literature

    White paper:

    Lighting for network video: Lighting Design Guide

    Axis Image Quality Tutorial

    All types of network camerasfixed, fixed dome, PTZ, and PTZ domecan offer dayand night functionality. A day and night camera is designed to be used in outdoorinstallations or in indoor environments with poor lighting.

    A day and night, color network camera delivers color images during the day. As light

    diminishes below a certain level, the camera can automatically switch to night mode to

  • 8/6/2019 Dome Cameras for CCTV

    8/12

    make use of near infrared (IR) light to deliver high-quality, black and white images.

    Near-infrared light, which spans from 700 nanometers (nm) up to about 1000 nm, is

    beyond what the human eye can see, but most camera sensors can detect it and makeuse of it. During the day, a day and night camera uses an IR-cut filter. IR light is

    filtered out so that it does not distort the colors of images as the human eye sees them.When the camera is in night (black and white) mode, the IR-cut filter is removed,

    allowing the cameras light sensitivity to reach down to 0.001 lux or lower.

    The graph shows how an image sensor responds to visible and near-IR light. Near-IR light

    spans the 700 nm to 1000 nm range.

    Image at left, IR-cut filter in a day/night network camera; middle, position of IR-cut filter

    during daytime; at right, position of IR-cut filter during nighttime.

  • 8/6/2019 Dome Cameras for CCTV

    9/12

    Day and night cameras are useful in environments that restrict the use of artificial light.

    They include low-light video surveillance situations, covert surveillance and discreetapplications, for example, in a traffic surveillance situation where bright lights would

    disturb drivers at night.

    An IR illuminator that provides near-infrared light can also be used in conjunction witha day and night camera to further enhance the cameras ability to produce high-qualityvideo in lowlight or nighttime conditions. More on IR illuminators

    At left, image without an IR illuminator; at right, image with an IR illuminator.

    Next topic: Megapixel network cameras

    Megapixel network cameras

    Megapixel network cameras, available in Axis fixed cameras and fixed dome cameras,

    incorporate a megapixel image sensor to deliver images with one million or morepixels. This is at least two times better pixel resolution than what can be provided by

    analog cameras.

  • 8/6/2019 Dome Cameras for CCTV

    10/12

    A megapixel, fixed network camera can be used in one of two ways: it can enableviewers to see greater details in a higher resolution image, which would be helpful in

    identifying people and objects, or it can be used to cover a larger part of a scene if theimage resolution is kept the same as a non-megapixel camera.

    Megapixel cameras today are normally less light sensitive than a non-megapixelnetwork camera. The higher-resolution video streams generated by a megapixel camera

    also put higher demands on the network bandwidth and storage space for recordings,although this can be mitigated by using the H.264 video compression standard.

    CTV-Speed Dome Camera

    Speed Dome Cameras can move side to side (pan), up and down (tilt), and zoom in and

    out (zoom). PTZ cameras are controlled either by a remote control, joystick, orcomputer software.

    What do I need to use a Speed Dome Camera?To use a Speed Dome Camera you will need 2 things.1) A display device. This is what will display the video of the Speed Dome Camera.

    This is often times a monitor, TV, or computer monitor.

    2) A device to control the Pan, Tilt, and Zoom of your camera. This is normally 1 of 2things. 1) The joystick controller that is sold along side of the Speed Dome Camera. 2)

    You use your computer's DVR card software to control the Speed Dome Camera. Wealso sell DVR card and software.

    Coming out of the Speed Dome Camera is the power connector, the video cable, and a

    the wires to control the Speed Dome Camera functions. The power cable connects to apower adapter. The video cable connects to your display device. It does not necessarily

    have to run to the same place the controls go. The Speed Dome Camera wires connectto either your joystick controller or Computer if you're using a DVR card.

    Can I use multiple Speed Dome Cameras?Of course you can. If you want to use multiple Speed Dome Cameras and control them

    from the same controller or DVR, you will need to do two things.1) Make sure they are all set to the same protocol and baud rate.

    2) Change the camera numbers so they are all unique. In addition to the baud rate and

    protocol, the camera also is assigned a camera number (1-255). Each Speed DomeCamera in your setup must have a unique camera number. These are normally changed

    via dipswitches on the cameras. Then, on the joystick, you just tell it to switch to thecamera number you want to control, and then control it.

    What is touring and cruising?Touring and cruising are two words that mean the same thing in the world of Speed

  • 8/6/2019 Dome Cameras for CCTV

    11/12

    Dome Cameras.With your Speed Dome Camera, you can program in presets.

    A tour or cruise is when the camera automatically moves from preset to preset in aspecified order.

    For example, you program in 10 presets (a door, window, sidewalk, cash register, etc).You then tell the camera (via the controller or DVR software) to tour the presets. It will

    then automatically go from preset to preset on a predefined interval.

    What are presets?

    Presets are an easy way for you to move your Speed Dome Camera from set location to

    set location. For example, you have a doorway, sidewalk, and hallway of particularimportance. For each of these location, you set the camera just right (pan, tilt, and

    zoom), and then assign it a preset number. Once this preset has been set, you can easilyand quickly get back to that same position. No matter where the camera is pointing, you

    can recall that preset and quickly jump back to the specified location.

    Speed Dome Camera AE-1806SD

    Speed Dome Camera ACV Series

  • 8/6/2019 Dome Cameras for CCTV

    12/12

    Speed Dome Camera ASV Series

    Speed Dome Camera AMV Series