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  • Nick Dragan 12:15 PM on 20/12/2018 Permalink | Reply
    Tags: #CCTV #security #seadan #cameras #domes #turrets   

    Cameras : Dome, Turret, Bullet, Full body, PTZ – Which one is The One ? 

    CCTV or surveillance cameras have been around for a very long time. And almost from the very beginning they presented themselves in various shapes. This is even more true today when our market is covered by at least 5 types of cameras and almost all of them with sub-divisions.
    The reality is that we could at a general level categorise the cameras by shape in 5 categories: dome cameras, turret cameras, bullet or tube cameras, full body and PTZ cameras.

    Let’s analyse each type a little to clarify the subject and bust some myths.

    1. Dome cameras
    These are the cameras that we have seen for a long time. They have a round shape, installed mainly on ceilings and sometimes on wall brackets and the video camera enclosed is covered by a clear plastic resistant bubble. There are some advantages to these cameras. Fist of all, the clear bubble protects the video element and its from projectile impact. The round shape naturally will deflect projectiles and chances are that any scratch will not immediately obscure or block the field of view.

    One other advantage is that in general, these cameras have a wider selection of lenses. Due to the geometrical placement of the camera and due to the housing enclosing the electronics, you can find these cameras fitted with lenses from 1.18mm (fisheye) all the way up to 35mm. Traditionally the dome cameras have been the preferred selection when it came to commercial applications such as high rise perimeter protection, shopping centres, etc. They are generally a little bit more expensive then their other brothers, the turret cameras.

    2. Turret cameras.
    Also sometimes called pig nose cameras due to their pig nose appearance in some designs, are becoming more and more popular. The turret cameras, such as the DAHUA 10514, benefit from the same electronics as the dome cameras. Due to manufacturing processes, these cameras cost a little less. Do to this fact, in large installations they have started showing up more and more. The turret cameras performance is today excellent. They can be found in extremely high resolution up 8MP , equivalent to 4K image. They can also be equipped with a range of lenses. The range is a little more restricted. Normally these cameras can be found in versions of 2.8mm lens up to 13.5 mm.

    Turret cameras can also be installed on ceilings, walls, on brackets and extension poles. They have one advantage. Because the way the lens in protected by a smaller window and due to the placement of this window, there is less chance of dust and dirt accumulating in front of the lens. Furthermore, the camera’s infrared projector is physically separated from the lens which also eliminates any infrared refraction and reflection into the lens creating a haze or halo effect in the image.

    3. Bullet cameras.

    Also known as tube cameras, have been around almost the longest, second only to the full body cameras. Tube cameras have many applications and one of their main advantage is that they can be equipped with very large range of lenses spanning from 2.8mm wide angle to 65mm zoom lens.

    From an installation point of view, these cameras are also protected from elements due to their shape and housing. One of the disadvantages is that because of their mounting option, they can be vandalise and lassoed. The general performance is excellent, Tube cameras can be found predominantly in the commercial and industrial applications. Because of the shape and the fact that their size is considerably larger than the dome or turret cameras, you will most likely not find them in residential applications.

    4. Full body cameras

    Full body cameras are the oldest shape. They have been installed on brackets, internally, in housings, etc. These cameras are perhaps some of the most flexible in terms of lens selection. Because they camera itself does not come with any lens, the installer can choose any lens that fits. Some of the cameras can also be fitted with adaptors which will allow SLR type lenses to be installed for special application such as space observation, etc.
    The number of full body cameras used has dropped recently due to the rise of the tube, dome and turret cameras. They are still used but because of the requirement of using extra housings, etc, the cameras’ applications is now limited to special situations. You will find these types of cameras more in licence plate recognition and special situations where extremely long range fixed cameras are required.

    5. PTZ Cameras

    PTZ stands for Pan, Tilt and Zoom. These cameras are easily recognizable due to their tear drop shape at the end of a goose neck bracket. They are generally bigger than any other cameras. Their internal mechanism makes them perfect for those applications where the operator needs to observe multiple points and wants to control the direction of the field of view. These cameras spin a great speeds, being capable of covering nearly 360 degrees in a couple of seconds or less.

    PTZ cameras are extremely versatile. They can be used in security applications, in industrial safety applications, in marketing (such as viewing the construction of a building in real time) , etc. They are generally the most expensive cameras of the 5 types but recently prices have dropped dramatically. The camera performance is today amazing. Some cameras come equipped with lenses offering up to 48x optical zoom which allows an operator to see extreme details at great distances.

    Now that we got the explanation out of the way, let’s bust some myths.

    Q. Are dome cameras better than turret cameras ?
    A. “Better” is a relative term. Today, the two types offer the same resolution. It depends on the application. Turret cameras are NOT lower in resolution, NOT less reliable and NOT less resistant to mechanical attacks such as vandalism when installed correctly

    Q. Are PTZ cameras a replacement for multiple cameras ? Would my investment be better in one or two PTZ cameras and less fixed cameras ?
    A. Not really. PTZ cameras perform a vital function. They allow a live operator to control the direction of the camera and the zoom level. However, we MUST remember that when the camera is controlled and turned in one direction, there is nothing to show the operator what happens behind the field of view. The better approach is a combination of shapes: fixed cameras for general view and PTZ cameras where required for detailed view.

     
  • Nick Dragan 4:52 PM on 04/01/2018 Permalink | Reply  

    The place of Wi-Fi and the rise of LPWAN technologies 

    LPWAN or low power wide area networks represents a new wave of technologies. This has been coming for a while. The novelty consists in the plethora of devices working directly on these networks. They are generally sensors, tags, small data packet senders which don’t need large bandwidth. One other excellent advantage is the fact that LPWAN devices use little power. Therefore they can be powered for months if not years with a single battery and utilising low power solar installations is really useful.

    If you do a search on the internet for any of the technologies available in this family you will find a real buzzing community. And the products keep coming. Furthermore, there is a huge number of city-wide networks being deployed and everyone is posting almost weekly a new signed agreement with a city or town.

    It is natural then to ask: what is the future of traditional Wi-Fi networks and is there a role for them in the new emerging trends ?

    I personally think that Wi-Fi has a pivotal role. Sure, you can use new low power networks to aggregate data from various sensors but there is a commercial reality. Many of the cities around the world have deployed in the past excellent Wi-Fi networks meant to cover high density areas and wide geographical spaces.  Installing new gateways is fine in a small area to collect information  from the surrounding sensor grid but carrying that information to the processing head end might be a commercial challenge.  This can be easily resolved by utilising existing infrastructure. A Wi-Fi link can connect gateways and nodes hundreds of metres away and even kilometres. There is no need for multiple hops. If there is nothing in between points other than a wide open space, then placing repeater nodes can be difficult.

    Existing mesh networks already deployed in places like universities, campuses, industrial estates and even residential communities can quickly solve the data transport challenge. The investment is already in place and quite often operators of such networks are unaware of the spare capacity. It is therefore extremely simple for example to create an air quality monitoring, irrigation and water level monitoring system by utilising local sensors with localised LPWAN gateways. Once the basic data collection or control equipment is in place, the gateways can be then attached to the already installed Wi-Fi network. No need for expensive extra power outlets, more radio infrastructure or co-location fees.

    Existing technologies are not , generally speaking, obsolete. Financial controllers and those who oversee investments will be very happy to re-use the systems in place while upgrading and increasing the data density for minimum cost.

     

     
  • Nick Dragan 11:44 AM on 30/10/2017 Permalink | Reply  

    NBN- Understanding Reality 

    Many stories – disaster or blessing ?

    For some time now I have read many stories and reports regarding the NBN. If you trust all that has been written so far, you would think that the Australian Governments of many colours have done nothing but bury billions of dollars into something that is in a state of total disarray.

    Is it true ?

    If we are to believe everything it has been said so far, we would rise like the eagle and really rally in front of the Government House to get our money back.

    But let’s use a little bit of our nature given intelligence.

    The mathematics behind statistics

    Most of us would have had some work done at our houses at some point in time. How would you feel about complaining that the toilet is not functional while the plumber is installing a new one ? What about complaining that the driveway is not useable while the brick paver works on it ? That would seem a little silly, wouldn’t it ?

     

    When the NBN started, say we had 1000 consumers connected in one suburb. Of the 1000, 2-3 experienced some sort of trouble. After that, we connected 100.000 consumers over several suburbs and the complaints went from 2 to 50. This is 25 times more

    Enormous ! Outrageous ! Skyrocketing ! Words of the media….

    But let’s not miss the point..

    The NBN is NOT finished ! The NBN is in construction. Now we have nearly 10 million subscribers on a network in construction and perhaps a few thousands complains on performance.

    I have personally went through troubles briefly with my NBN connection (fibre-to-the-node) and I solved it with my provider. No need for a big whinge.

    Perhaps we should take a step back and really understand what is happening.

    I personally believe that consumers are too much into the “I want it now, I deserve it now” attitude. You can’t drive your car when the wheel is out. You have to wait. Similarly, the NBN will experience sometimes dropouts and reduction in speed temporarily. It will pass.

    I am sure that when it works nobody calls to say ” Thank you NBN for making my internet faster”.

     
  • Nick Dragan 5:29 PM on 12/09/2017 Permalink | Reply  

    Technical solutions = The outcome of collaboration 

    Great technology Solutions come from open and honest collaboration between hardware suppliers, service providers or integrators and customers. The intersection of these three realms represents the outcome.

     

     

    What are your thoughts ? Is this your experience ?

     
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