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In this day and age we hear many tragic tales of loss and destruction to property, in fact it is fast becoming the norm to have a neighbor who's bin was set on fire, or whose house was vandalized. You probably just assume that if you insure your goods then you will be able to get the money back if anything is stolen. Well I am here to tell you that insurance is not always such an easy thing to claim. These are big companies who are simply not too fond of paying out, and it is often hard to prove that you had that 52" television in the first place.
With security cameras in place you cannot just find out what happened but what is happening, that means you can act and perhaps stop something before it's too late. That's something that no other system of surveillance can offer.
Here we have covered the most important elements impacting the selection of security cameras.
Security Cameras Form Factor
Specifying a form factor in security cameras is generally necessary only if you are concerned about (1) aesthetics or (2) cost. Otherwise, the other functional specifications will naturally impact the type of camera to select.
Among fixed security cameras, the fundamental form factor options are box, bullet, cube and dome. Most people who care about aesthetics (i.e., minimizing the obtrusiveness of a camera) prefer domes. Specifically, users who want to make security cameras as inconspicuous as possible prefer mini-domes. If this is an important factor for your use case, you should require domes or mini-domes.
Most people who want the cheapest solution possible prefer cube security cameras. However, some people really dislike the look of cube security cameras (often they look clunky and 'cheap'). If you want to avoid this, specifically exclude cube security cameras in the requirement.
Frames Per Second
Specifying the camera's frame rate is almost always included. The only practical question is what frame rate to select. This is a point of great practical contention with two major camps - the 'good enoughs' and the 'pursits'.
The 'good enoughs' argue that surveillance video does not need to look like a movie to solve incidents. Almost no practical action is missed in between frames even at 5fps. Users are better off at a low frame rate that meet security purposes needs and saves significant storage expenses (higher frame rate, more storage - not linear but close).
The 'purists' argue that surveillance video should be full frame rate to ensure that nothing is missed. They also argue that the cost of storage continues to decline so the price premium should not be significant.
Security Cameras Resolution
Resolution requirements are almost always included in specifications yet fixating on resolution can lead to sub-optimal surveillance solutions. Generally, a specification will require security cameras to be VGA, 720P, 1.3MP, etc. Often, indoor security cameras are SD (VGA) and outdoor security cameras are megapixel. In the past, when megapixel options were limited, it was simple enough to require all SD. Today, you are seeing more organization standardize all security cameras on megapixel (i.e., every camera is 1.3MP, etc.).
The problem with specifying resolution first or specifying a single resolution for every camera is that different cameras will have varying coverage areas. For example camera #1 might only need to cover a 10 foot wide area where camera #2 might night to cover a 20 foot wide area. If you use the same resolution, users are likely to be disappointed or upset about why the quality / level of detail is so much poorer for camera #2 even if the same model and settings are used for each camera.
An alternative to setting resolution is to define (1) the main target of the camera, (2) the pixels per foot needed and (3) the horizontal field of view for that target. Doing this will deliver a specific resolution requirement that better meets your operational / security objectives.
Low Light
Surveillance in low or poor lighting conditions can affect quality to a great deal. This is one of the most difficult aspects to specify as the fundamental metric used, lux rating, is completely unreliable.
The key feature that we have found to differentiate good results in low lighting is the inclusion of a mechanical cut filter. In the dozens of security cameras we have tested, basically security cameras with a mechanical cut filter has demonstrated better performance than any camera without one - regardless of resolution or sensor size.
Furthermore, within security cameras possessing mechanical cut filters, we have not seen dramatic differences in low light performance.
We recommend requiring a mechanical cut filter for any scene where lighting is not strong at any time of the day/night recording is desired. Most models support mechanical cut filters and the price premium is under $100 - a relatively low sum for the benefits it provides.
Distance from the Camera
Distance from the camera is generally overlooked in camera specifications. However, it is important in determining the length of lens used and often indirectly the type of camera.
If the target is within 5 - 15 feet of the camera, most security cameras will be able to meet this specification. However, when the target is farther away, a special lens may be needed. For instance, a user mounts a camera on a wall and wants to see facial details clearly at an entrance over 50 feet away. Almost, no stock lens provided with security cameras will cover this distance. Worse, some security cameras, such as some domes, cannot physically fit the larger lenses required for this distance. Whenever possible, estimate the distance from the camera to the main target / viewing area for the camera and include it in the specification.
We recognize that this can be challenging since estimating the distance from the camera to the main target assumes knowledge of the camera's positioning. The exact camera positioning may not have been determined at this stage. However, if you believe that security cameras will be mounted for away from its target, it is very useful to note this up front so that the appropriate product can be selected.
Security Cameras Audio
When specifying audio, we recommend factoring 3 issues:
• The type of audio desired: Manufacturers offer 4 types of audio: microphone only, speaker only, half-duplex and full duplex (half duplex is like a walkie talkie, full duplex is like a telephone). Do not simply specify audio. Specify the specific type of audio needed for the application.
• Whether audio is really needed: Audio is very rarely used. Most industry people cite usage rates of under 5%. Requiring audio eliminates many of the less expensive. In the last few years, an increasing trend has been to only include audio in premium tier camera offerings.
• Whether audio is legally allowed: Many countries and regions have strict regulations or restrictions against using audio surveillance. Even in the US where lax regulations on surveillance is common, 12 states essentially prohibit audio surveillance as both parties (i.e., the company doing the surveillance and the person on the premises) need to provide consent (not practical in most surveillance applications). See more on audio surveillance legality and consent issues.
Multi-Streaming
Normally, a single video stream is sent from camera to a VMS system. However, some advanced VMS systems can support multiple video streams from a single camera to a VMS. This is often used when an organization wants to view live video at different quality levels than recorded video or when server side video analytics are deployed.
Most, but not all security cameras support multi-streaming. Also, many security cameras support multiple streams but only at reduced bit rates (e.g., a 1.3MP camera may support 2 streams but only 1 at 1.3MP and the other at VGA). If the application plans to use multi-streaming, call this out in the specification. If the scenario calls for multiple high frame rate, high resolution streams, require this explicitly.
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