BUYER GUIDE FOR CCTV SOLUTIONS

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OVERVIEW

Today’s security camera system equipment is smaller, less expensive, more sophisticated, and is packed full of features. This is great for you as the consumer as you have more high quality options at your fingertips than ever before! However, there are a ton of options and it can be very confusing telling the difference between two particular products if this is your first time dealing with the security industry. You’re going to come across a lot of terms, types of products, and information that you might have never heard of before, but that’s okay! We’re here to help out with that and make this process easy for you. If you have any questions while you read this guide, give us a call at +88 01973432329 or email: info@optimal.com.bd or visit our official website www.optimal.com.bd and we’ll help however we can!

SECURITY CAMERAS

Security cameras come in a wide variety of shapes, sizes, and types with each kind of camera having different sets of features for different environments. Select one of the options below to learn more about each type of camera.

GENERAL INFORMATION

This section will help you understand basic camera specifications and their effect on the performance of the camera. Analog camera resolution or picture quality is measured by the number of horizontal lines the sensor chip in the camera provides and is called “TV lines of resolution” or TVL. Naturally, the higher TVL values the better the quality of the image.

  • Standard Image Quality: 380TVL – 420TVL.
  • High Image Quality: 480TVL – 520 TVL
  • Very high Image Quality: 540TVL – 700TVL

TVL is defined as the maximum number of alternating light and dark vertical lines that can be resolved per picture height. A resolution of 400 TVL means that 200 distinct dark vertical lines and 200 distinct white vertical lines can be counted over a horizontal span equal to the height of the picture. For example, on 4 by 3 inches (10.2 cm × 7.6 cm) monitor with 400 TVL, 200 vertical dark lines can be counted over 3 inches (7.6 cm) width on monitor (Note that the 3 inches (7.6 cm) of monitor height is used rather than the 4 inches (10 cm) of whole monitor width).

TVL is an inherent quality of a camera or monitor and should not be confused with the horizontal scanning lines of broadcast television systems, which e.g. for a PAL system are 625 lines, and for the NTSC system 525 lines.

Infrared LEDs allow security cameras to see in dark areas by flooding the area with infrared light. This light reflects off surfaces in the area and is picked up by the camera’s sensor chip which allows the camera to see as if the area was lit by visible light.

  • # of LEDs: The more LEDs, the better a camera can see in low light environments.
  • Illumination Rage: Refers to the maximum distance at which an object is visible at night.

Indoor VS Outdoor Cameras
CCTV Cameras use electrical components that are sensitive to the elements. If water or dust gets inside of your camera, the quality of your video feeds will suffer and your camera may even stop working. Weather proof housings help keep moisture and dust where it belongs, on the outside.

If you are installing a camera outside and it is not in weatherproof camera housing, you will definitely want to double check the camera specification to make sure that it is weather resistance rated. There are many different levels of weather resistance that range from minimal protection all the way to airtight, waterproof enclosures and all of our outdoor cameras are fully weather resistant.

Infrared (IR) Security Camera
An IR Illuminator allows a camera to see in total darkness, when there is insufficient light to see. This can be useful for security applications, especially covert needs, or maybe when keeping an eye on the night activities of the local wildlife.

Infrared cameras convert ambient light photons into electrons which then are amplified through an electrical process and converted back into visible light. Infrared light should not be confused with thermal imaging, which creates images based on differences in surface temperature between what an object radiates and the environment around them.

Cameras and infrared illuminators are a great duo for covert surveillance. However, there are things you should know before you purchase and deploy. Here are some things to consider:

  • Frequency
  • Range
  • Co-Location
  • The Right Camera
  • Optics
  • Weather Ratings
CCTV Camera Lenses
Naturally, lenses are on every security camera and have a dramatic affect on the area that the camera can monitor. Installing a security camera with the wrong type of lens can make that camera’s video feed of little use. A good rule of thumb to keep in mind when shopping for cameras is the smaller the lens’ focal length, the mm spec, the wider your field of view will be. For example, a camera with a 50mm lens will have a very narrow field of view (FOV) and be able to focus on objects far away while a 3mm lens will have a wide FOV and be more suited for short range monitoring.

Varifocal vs. Fixed Lenses

A fixed lens is a lens that has a set focal length which you’ll see as a ‘x’ mm specification. These lenses are only capable of viewing people / objects / areas a set distance away from the camera which will affect where you can install the camera.

A varifocal lens is a lens that has an adjustable focal length which you will see as an ‘x-y’ mm specification. This allows the lens to be adjusted to view people / objects / areas at a distance of your choosing, grants you more flexibility with camera placement, and gives you more control on the focus clarity of that specific camera. Each type of lens will aid in the capture of video regardless, but the varifocal lenses allow much more flexibility in the installation of a security camera system and it’s allow you much more control over the quality of your video feeds.

INFRARED LED OF CAMERA

INDOOR VS OUTDOOR CAMERAS

INFRARED (IR) SECURITY CAMERA

CCTV CAMERA LENSES

VARIFOCAL VS. FIXED LENSES

CCTV Camera Lenses
There are many security cameras available and it would be impossible to cover them all in this guide. Security cameras produce images using CMOS (Complementary Metal Oxide Semiconductor) or CCD (Charge Couple Device) sensor chips. The size of the chip is normally 1/4″, 1/3″ or 1/2″. As a rule of thumb, the larger the chip size, the higher the quality of the image produced and the higher the price. As technology has advanced, higher density 1/4″ and 1/3″ CCD chips can now produce as clear of an image as the older 1/3″ & 1/2″ chips.

Most cameras have the industry standard 3.6mm lens that provides roughly a 72 degree field of view (FoV). Figure 1.2 shows some popular lenses and their respective field of view:

FIGURE 1.2

Field of View (FoV):

The field of view (FOV) is the height and width of the picture size produced by a lens. FOV can be adjusted by using a different lens on your camera. There are two basic types of camera lenses: fixed focal (or monofocal) and varifocal (or zoom). FOV of a fixed focal lens cannot be adjusted. FOV of a varifocal lens can be adjusted. Varifocal lenses are usually more expensive.

 

Figure 1.3 illustrates the FOV of various lenses.

Detailed Lens Chart

5 feet

10 feet

25 feet

50 feet

75 feet

100 feet

2.8mm

6.4 X 8.6

12.9 X 17.1

32.1 X 42.9

64.3 X 85.7

96.4 X 128.6

128.6 X 171.4

4.0mm

4.5 X 6.0

9.0 X 12.0

22.5 X 30.0

45.0 X 60.0

67.5 X 90.0

90.0 X 120.0

6.0mm

3.0 X 4.0

6.0 X 8.0

15.0 X 20.0

30.0 X 40.0

45.0 X 60.0

60.0 X 80.0

8.0mm

2.3 X 3.0

4.5 X 6.0

11.3 X 15.0

22.5 X 30.0

33.8 X 45.0

45.0 X 60.0

12.0mm

1.5 X 2.0

3.0 X 4.0

7.5 X 10.0

15.0 X 20.0

22.5 X 30.0

30.0 X 40.0

16.0mm

1.1 X 1.5

2.3 X 3.0

5.6 X 7.5

11.3 X 15.0

16.9 X 22.5

22.5 X 30.0

25.0mm

0.7 X 1.0

1.4 X 1.9

3.6 X 4.8

7.2 X 9.6

10.8 X 14.4

14.4 X 19.2

50.0mm

0.4 X 0.5

0.7 X 1.0

1.8 X 2.4

3.6 X 4.8

5.4 X 7.2

7.2 X 9.6

75.0mm

0.2 X 0.3

0.5 X 0.6

1.2 X 1.6

2.4 X 3.2

3.6 X 4.8

4.8 X 6.4

 

Figure 1.3

 

By knowing the object distance and the required target area, you can determine what lens is going to give you the best image.
For example, using the chart above for a 1/3-inch format camera, viewing an object at a distance of 50 feet with a target area of 15 feet by 20 feet, scan down the “50 feet” column to the stated target size; scan left to see that a 12mm lens is required for that area.

 

Auto Iris VS Manual Iris

Auto iris lenses are a fantastic choice for outdoor surveillance where light is constantly changing. The iris for these lenses automatically opens and closes according to the amount of ambient light so that your video feeds are not affected by the change in lighting conditions.
Manual iris lenses are well suited for areas with consistent lighting like shopping centers, schools, libraries, and offices because the iris only needs to be set once during the installation of the lens.
Manual lenses are less expensive than their auto counterpart since they do not come with the auto- adjust mechanics, but are more limited because of that distinction.

 

Network IP Cameras

Analog security cameras have long been the standard type of camera used in surveillance systems, but IP cameras have surged in popularity over the last five years. When IP cameras were introduced, they were prohibitively expensive and didn’t produce noticeably greater quality videos than analog cameras did. However, as the technology has become more readily available and more surveillance companies have invested in developing this technology, IP cameras have dramatically increased in quality and decreased in price which has made them more affordable than ever!
IP Camera popularity is on the rise and it is estimated that over 60% of all security camera systems sold over the next few years will be IP based. The advantages of IP cameras over analog cameras are below.

Higher Resolution and HD Video

Megapixel IP cameras can capture High Definition Video (HD Video) and provide greater detail improving identification. A 2 megapixel camera is an excellent choice for capturing license plates and can cover a 24 foot wide point of entry or exit.

 

When monitoring an area, a megapixel camera provides superior image quality compared to analog cameras. We illustrate this below by comparing an analog, 1.3MP, and 2MP image, the license plate in the 2MP image can be easily identified when zoomed into, but this is not the case at an analog resolution.

 

When you need a clear shot of what a person looks like, a megapixel camera image can provide a level of detail that can’t be matched by an analog camera. The improved pixel count also allows for the use of ePTZ technology.

HIGHER RESOLUTION AND HD VIDEO

Electronic Pan/Tilt/Zoom (ePTZ)
Zoom has always been available with analog cameras, but is often slow and can only be used on live video as events occur and you can’t zoom in for more details with a PTZ camera.

With megapixel IP cameras, you can zoom, pan, and tilt on live footage and your previously recorded video! The NVR software allows you to select a video clip and zoom in on any part that you want. This lets you catch all the details regardless of when the video was recorded!

Wider Camera Coverage
One of the factors that has contributed to the explosive popularity of megapixel IP cameras is their ability to provide wider coverage and more detail on a per camera basis. A single 2-megapixel IP camera can cover an area 6 times greater than an analog camera. With a 2-megapixel camera potentially taking the place of 6 Analog cameras, the installation costs can be significantly reduced.

This is especially true for fisheye IP cameras that come with a special fisheye camera lens. This type of camera records everything in a 360° view and comes in models up to 5 megapixels for high definition video resolution. One single fisheye IP camera can cover a 3,000 square foot warehouse with ease!

Lux & Light Sensitivity
The light sensitivity of a camera is measured in Lux and this is the standard specification you will see that defines how well a camera can see in poor lighting conditions.

Lux is the SI unit of luminous emittance used in photometry as a measure of the apparent intensity of light hitting or passing through a surface. IR cameras have a 0 lux rating as they illuminate in total darkness. Some cameras are known as Day/Night and have very low lux ratings indicating it needs only a small amount of light to capture images in darkness. The chart below is an example of how much light is produced from certain sources measured in lux. If a camera has a lux rating of 0.1 and gets light equivalent to that of a full moon, it will be able to produce an image.

We’ve compiled the table below to give you a better understanding of the concept.

Lux & Light Sensitivity
The light sensitivity of a camera is measured in Lux and this is the standard specification you will see that defines how well a camera can see in poor lighting conditions.

Lux is the SI unit of luminous emittance used in photometry as a measure of the apparent intensity of light hitting or passing through a surface. IR cameras have a 0 lux rating as they illuminate in total darkness. Some cameras are known as Day/Night and have very low lux ratings indicating it needs only a small amount of light to capture images in darkness. The chart below is an example of how much light is produced from certain sources measured in lux. If a camera has a lux rating of 0.1 and gets light equivalent to that of a full moon, it will be able to produce an image.

We’ve compiled the table below to give you a better understanding of the concept.

Infrared technology (IR) refers to the cameras ability to capture images in total darkness. Cameras featuring IR product color images during daylight and switch to black and white at night. When choosing this feature, you will want an accurate measure of the distance you need illuminated at night. Some cameras are equipped with more IR lights than others and therefore are capable of producing longer range images at night.

Video Analytics
Video analytics is an industry term for software features and it covers a wide variety of useful functions from missing object detection to tampering alarms. Using a digital video recorder or network video recorder with analytics is like driving a fully loaded car, you may not need all of the features, but they sure are nice to have!

The biggest benefit from using video analytics is that you don’t have to sit a person in front of your security monitors all day watching video feeds in case something goes wrong. By putting in a little bit of time configuring your settings, your DVR or NVR can do all the work for you while you spend your time doing things that are more important to you!

Video Analytics, also known as smart video surveillance, is the emerging technology where computer vision is used to filter and manage real time CCTV video for security and intelligent traffic monitoring.

A Surveillance system of CCTV cameras and Digital Video Recorders (DVRs) gives a user the ability to review footage that has been recorded, but how practical is a surveillance system if it is only of use after the event? Intelligent security camera analysis provides the user real-time video surveillance of their property.

Video Analytics Features

  • Missing Object Detection: Detects when an object goes missing and sends an alert
  • Motion Detection: Detects motion and cues the DVR to record
  • Unattended Object Detection: Detects when an object is left and sends an alert
  • People Counting: Counts the number of people or objects entering / leaving an area
  • Scene Change Detection: Detects when a camera’s field of view is changed and sends an alert
  • Face Detection: Detects facial features and saves the image to a thumbnail index for quick recall
  • And many more!

Video Recorder Equipment
There are 3 basic types of video recording equipment: PC-based Digital Video Recorders (DVRs), Standalone DVRs, and Network Video Recorders (NVRs). Each of these video recorders has their own strengths and the proper selection will help you get the most out of your system. Knowing which one is more suited for your location will not only help you save money, but help you get the absolute most out of your system!

PC Based DVRs
A PC based DVR is a windows based computer that includes a 4,8,12,16 or 32 channel DVR card. Most DVR cards feature CMS software that offers significantly more options and customizations than the Standalone DVRs. Initial setup of a PC based DVR is more expensive, but you do have increased flexibility when adding cameras and storage.

PC Based DVR Benefits:

  • High Resolution Recordings (720×480)
  • Upgrade flexibility
  • Feature rich, user friendly interface
  • Storage capacity
  • Easy network integration

Limitations:

  • Windows based OS increases vulnerability to virus attacks and software crashes.
  • Users must have some basic computer knowledge

Standalone DVRs

Standalone DVRs are machines are based on Linux, UNIX or other proprietary operating system. Designed for a single application, they are simple to use and offer many features. They are commonly available in 4 channels, 8 channels and 16 channels and typically include central management software (CMS) for remote viewing, PTZ control, live and recording playback options and motion detection.

Standalone DVR Benefits:

  • High Resolution Recordings (720×480)
  • Feature rich, user friendly interface
  • Very stable and low maintenance
  • Easy network integration
  • Low cost

Limitations: Proprietary OS decreases flexibility with upgrades and storage capacity.

Network Video Recorders (NVRs)
A network video recorder (NVR) is a software program that records video in a digital format to a disk drive, USB flash drive, SD memory card or other mass storage device. An NVR contains no dedicated video capture hardware. However, the software is typically run on a dedicated device, usually with an embedded operating system. An NVR is typically deployed in an IP video surveillance system.

Network video recorders are distinct from digital video recorders as their input is from a network rather than a direct connection to a video capture card or tuner. Video on a DVR is encoded and processed at the DVR, while video on an NVR is encoded and processed at the camera, then streamed to the NVR for storage or remote viewing

Competent NVRs now embody features:

  • Hot-swappable disks
  • SNMP support
  • Built-in diagnostics
  • Protection of files against deletion
  • File export function
  • Digital signature based video
  • Synchronized audio and video recording
  • Hard-disk temperature monitoring
  • Dual, fully redundant power supplies

Video Compression
MPEG4 and H.264 are the most popular video compression choices. The key to video compression is the resolution and the size of the video. High resolution video files are monster size files and video compression for storage and streaming is critical to any video application. H.264 is the preferred compression method because it provides high resolution video quality from the smallest amount of video data required. Smaller files require less bandwidth and storage over previous generations of video codec’s. H.264 delivers the same quality as MPEG-2 at a third to half the data rate and up to four times the frame size of MPEG-4 Part 2 at the same data rate.

Recording Speed
The speed of recording is a critical part of any CCTV application. To have a smooth, gapless motion video, you must be able to real-time. A video is considered as real-time video when its recorded at 30 fps (frames per second). This ensures a consistently smooth video.

NVR Storage Calculator for Network IP Security Cameras
Another important feature of a Video Recording is its storage capacity. When configuring how much storage you need, you must consider the following:

  • How many days of video do you want to store?
  • How many numbers of cameras recording?
  • Frames per second each camera is recording?
  • How many hours per day to record?
  • How many days of the week to record?

This is a very common question with a very simple answer; it depends. For those of you looking for a more complete answer I will go a little deeper. The amount of recording time the DVR/NVR can save is based on a few variables. They are the Hard Drive Size,Record Mode, Record Quality, Frame Rate, and Record Size.

ELECTRONIC PAN/TILT/ZOOM (EPTZ)

WIDER CAMERA COVERAGE

LUX & LIGHT SENSITIVITY

VIDEO ANALYTICS

VIDEO RECORDER EQUIPMENT

PC BASED DVRS

STANDALONE DVRS

NETWORK VIDEO RECORDERS (NVRS)

VIDEO COMPRESSION

RECORDING SPEED

DVR/NVR

SECURITY CCTV SYSTEM SCHEMATIC

Hard Drive Size: When it comes to the hard drive the bigger the drive the greater the storage capacity. Typical size for a basic drive should start at 500 gigabytes and can be as much as 2 terabytes. Depending on the DVR/NVR it can hold multiple drives for a stacked effect. Some machines can hold as many as 12 terabytes. That is a whole bunch of storage!

Record Mode: The mode you record in makes a big difference for the average user. The two most common options are 24 hour and motion only. 24 hour is exactly how it sounds. It never stops recording, which means it never stops filling hard drive space. Motion recording is great for locations with “downtime”. Businesses that operate from 9-5 will save a large amount of space during non business hours when there is nothing setting off the motion alarms triggers. I recommend motion in most every case. No motion = No recording, which equals more record time or less usage of Hard Disk/ Storage

Record Quality: This may seem a little silly but there are applications where it is not necessary to get high quality recording. However, we generally recommend the best quality setting for all cameras. When you lower the quality of the recording you are storing less data. Less data = less storage and more record time of your Hard Disk.

Frame Rate (FPS): The average movie records and plays at 24 fps (pictures/frames per second). Real time recording for DVR/NVR systems is 30 fps. In most cases 15 frames a second looks pretty good but may miss some details that would be of great help in theft, slip and fall, and many other incidents. Unless storage time is a real problem, we always recommend 30 fps.

Basically, more frames = more picture and more picture = more data, which equals less record time and need more Hard Disk/ Storage

Record Size: Similar to record quality, record size changes the amount data placed on the hard drive. In most cases the standard recording is done in (352 x 240 resolution) of CIF. The industry uses this as the basis for all the formulas for recording time. In most cases CIF is a reasonable record size. The larger frame, the more data, which equals less record time and need more Hard Disk Space.

In a typical scenario, a camera system will use about an average of 8.42GB of storage space per camera per day in motion mode

Number of Camera 1 (One Camera) 1 (One Camera) 1 (One Camera) 1 (One Camera) 1 (One Camera) 1 (One Camera)

Camera Stream

(Compression Codec)

MPEG-4 MPEG-4 MPEG-4 H.264 H.264 H.264

Camera

Resolution

1 Megapixel (1280×1024)

2

megapixel (1600 x

1200)

3 Megapixel (2048×1536) 4CIF (704×480) CIF (352×240) QCIP (176×120)
Video Quality Medium Medium Medium Medium Medium Medium
Average Frame Size 14.44KB 21.33 KB 35 KB 2.85 KB 1.083KB 0.35 KB

 

Frame Rate Per

Camera

30 30 30 30 30 30

Per Camera will

record

24 Hours

Per Day

24 Hours

Per Day

24 Hours

Per Day

24 Hours

Per Day

24 Hours

Per Day

24 Hours

Per Day

Bandwidth Required 5.2Mbps Per Camera 7.68 Mbps Per Camera 12.60 Mbps Per Camera 1.03 Mbps Per Camera 390 Kbps Per camera

128.57

Kbps Per Camera

Estimated Storage 112.32 GB 165.89 GB 272.16 GB 22.22 GB 8.42 GB 2.78 GB

Please calculation your own storage considers the above matrix. We hope this guide has been helpful to you. If you have any questions, please do not hesitate to call our knowledgeable presales engineers team at +8801973432329 or email info@optimal.com.bd for expert advice.

About the author

Optimal Technology Ltd.

Optimal Technology Limited (OTL) is a leading Enterprise Networks Solutions, Structure Cabling (Copper & Fiber) Solutions, Data Center Design, Wireless Networks Solutions, IP Telephony Solutions, Video Conferencing Solutions, IP PA System, IP CCTV System, Raised Floor System, Fire Suppression System, Server Racks/Cabinet, Smart-UPS for Data Center, and Audio Conference Solutions provider in Bangladesh. Our staff can help! Connect with us for a free consultation or discuss an upcoming project, contact us: Mobile: 01973432325-26, 01973432328 Email: jay@optimal.com.bd, atiq@optimal.com.bd

Website: https://www.optimal.com.bd

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