Varifocal Dome and Bullet Cameras – When To Use Adjustable Lens IP Cameras

A varifocal lens is an adjustable camera lens with independently adjustable focus and zoom. This is usually done using a pair of knobs or rods located near the lens of the camera. In this article, we will outline when it is beneficial to use a varifocal bullet or dome camera.

Understanding Angle of View

The Angle of View is an important factor in deciding which camera to use and where to position it. A wide angle is great for capturing a large area, but it is hard to recognize a face from more than 40 or 50 feet away, even with a 1080p camera. A narrow-angle makes it possible to recognize someone’s face from 75 and even up to 100 feet away with a 4MP camera using digital zoom, but the area you can cover is more limited.

The shorter the lens length (or focal length), the wider the angle of view is for that camera. For example, a 2.8mm lens will have a slightly wider angle of view than a 4mm lens. Arcdyn varifocal dome and bullet cameras are adjustable from a 2.8mm setting to a 12mm setting. This means that when you have the lens set to 2.8mm, or the zoomed out setting, you have roughly a 95˚ Angle of View, and when you have the lens adjusted to 12mm, or zoomed in, you have roughly a 30˚ Angle of View.

Specific Uses for Narrow Angle of View

A varifocal camera can be useful if you want to focus on the end of a longer driveway, to a distant gate or property entrance, or on a dumpster at the far end of your business’ parking lot to prevent illegal dumping.

There are many unique scenarios that might benefit from the use of a varifocal camera, using a tool like our Angle of View Calculator can help you decide the best lens length for you.

This is the same shot taken with a 2.8mm and a 12mm lens with the target standing 75 feet away.
The same shot taken with a 2.8mm and a 12mm lens.

Tips for Adjusting a Varifocal Camera

Finding the perfect setting for your varifocal camera can be a little bit tricky, but there are a few tips and tricks you can do to make it easier on yourself when installing Varifocal cameras.

The first is to get your remote viewing app configured before installing and adjusting the camera. That way you can view the camera live on your smart phone while you install the camera. It is also helpful to have a helping hand to watch the camera while you install the camera, that way you have both hands available when up on a ladder.

If you think you may need to adjust the level of zoom periodically, you should consider a varifocal camera with a Motorized Lens. All of our HD+ Varifocal cameras have a motorized lens that will allow you to adjust the zoom and focus from the NVR or your smart phone. This is different from a PTZ camera since you can only Zoom, but you cannot Pan and Tilt.

What are Smart Security Cameras and Analytics?


What are smart surveillance cameras?

Smart Security cameras are advanced cameras that feature a robust set of configuration tools to help secure your area. These Advanced Analytics have revolutionized traditional surveillance systems with advanced features and alerts. These features are most commonly found in IP security cameras. Different Security cameras will have different features. I am going to cover our Bolt 4k bullet camera and the smart features on that particular camera. Read the Full Article

Do Surveillance Cameras Actually Deter Criminals?

Most security professionals will say that installing surveillance cameras on the outside of your home or business is an effective method of deterring criminals from choosing you as a target. Is this just a marketing pitch to get you to buy cameras, or are there actual statistics to prove this?

The University of North Carolina at Charlotte conducted a study in 2012 that sheds light on the subject and gives us a better understanding of what is going on in a burglar’s mind when selecting a target. The University’s study, titled “Understanding Decisions to Burglarize from the Offender’s Perspective,” surveyed 422 incarcerated male and female burglars and asked them a number of questions about choosing a target, motivation for burglary, and the question that we will focus on in this article; the effectiveness of alarm and security camera systems.

What deters burglars from burglarizing specific targets?

The data reflects that a significant majority of offenders were influenced by the presence of security systems. About 83% of the offenders would try to determine if there was an alarm before pursuing a target, while roughly 60% said that such a system would cause them to choose another target.

In the event that the burglar noticed Surveillance Cameras or triggered an audible alarm after they had begun the attempt, 50% of offenders said that they would discontinue the robbery, 37% said that they sometimes still went through with the burglary, while 13% said that they always continued with the attempt.

“Within this broad set of potential target hardening deterrents, alarms and outdoor cameras and other surveillance equipment were considered by a majority of burglars.”

Figure 1: Graph from Joseph B. Kuhnz. Understanding Decisions to Burglarize from the Offender’s Perspective
Figure 1: Graph from Joseph B. Kuhnz. Understanding Decisions to Burglarize from the Offender’s Perspective

Surveillance cameras prove to be among best deterrents against burglary.

Taking Additional Steps To Secure Your Location

Other factors that deterred offenders included having neighbors, pedestrians, and frequent vehicular traffic near the home or business. Many offenders also admitted that they would decide against attempting a burglary because there were no viable escape routes. The data shows that the two best deterrents were residents inside of the establishment and having a police officer in close proximity.

Since it’s not realistic to be at home 100% the time or to ensure that a police officer is near your home at all times, the best way you can deter a break-in from happening to your home or business is to put up Surveillance and Alarm systems.

Summary: A 2012 study shows that having a surveillance and alarm system can prevent your home or business from becoming a target. To learn more about what it takes to plan and install a surveillance system in your home, check out some of our other articles. You can also call us at 855-272-6682 or get in touch with us on our Live Chat.

Source: Kuhnz, Joseph. “Understanding Decisions to Burglarize from the Offender’s Perspective.” December 2012. IP Security Camera Vulnerability – Never Fixed After 3 Years


Originally posted to the /r/homedefense subreddit on Sept 30, 2013 by reddit user ahmadnassri, an exploit that could potentially expose your entire network to hackers has been released to the world. On Jan 10, 2017 ahmadnassri released a full walkthrough on how to hack into an system and gain access to an extensive list of private data and devices.

The exploit was achieved by decompiling the JAVA player responsible for streaming live video feeds from the camera system. This gives a would be hacker easy access to’s Master Key and in turn your camera system. While this exploit only applies to older models sold by dealers such as Vivint and Frontpoint Security, there are plenty of these models in the wild to cause concern.

The release of yet another security flaw found in security cameras and devices adds to the long list of vulnerabilities found in recent memory. Until the security industry and manufacturers that are creating devices for the Internet of things begins to take network security seriously we will continue to see dangerous exploits found and utilized.

In most cases, changing the default password on your equipment will protect you from an attack, but that unfortunately is not a sure bet when using cheap or poor quality systems. The old adage “you get what you pay for” always turns out to be true and in this case could mean the difference between your security or being a target.

Check out Arcdyn for professional and secure IP security camera systems

What does 1000TVL mean? Avoiding Misleading Resolutions

Don’t Let Misleading Numbers Fool You

If you’ve been researching security cameras for a while, you have probably noticed that some cameras measure resolution using TVL (600TVL, 700TVL, 1000TVL) rather than 720p, 1080p, or Megapixels. This can be confusing and even misleading, which can make it very frustrating to figure out what you need for your home or business. In this article we’re going to break down what all of those numbers actually mean so that you can make an informed decision.

The 1000TVL Gimmick

1000TVL cameras are the best (or worst) example of this. At a glance, you might think that 1000TVL resolution is comparable to 1080p resolution, but there is a huge difference between the two.

Measurements in TVL refer to the horizontal pixels of the image, while HD resolutions measure the vertical pixels on the image. This means that 720p, which is 720 pixels tall by 1280 pixels wide, is actually a better image than 1000TVL.

This is a scheme with the goal of getting you to spend top dollar on subpar equipment. Even with “1000TVL cameras,” you can hardly recognize a face or read a license plate from more than 10 feet away, and what good is video footage if you can’t tell what you’re looking at?

TVL refers the horizontal pixels on your monitor.  HD resolutions measure the vertical pixels. TVL refers the horizontal pixels on your monitor. HD resolutions measure the vertical pixels.

There is no “1000TVL DVR”

Analog DVRs usually record in 480TVL (D1), 600TVL, 650TVL, or 700TVL (960h), and the absolute highest resolution that an old Analog DVR can view is 720TVL. If you are hoping to hook up a 1000TVL camera and get better resolution on your existing analog DVR, you will be disappointed when you only get 720TVL. It doesn’t matter how good the image sensor is in the camera, because as far as Resolution goes, your system is only as strong as your weakest link.

TVL has Always Been Deceiving

TVL as a measurement standard has always been mostly made up since the beginning. When TVL was the normal way to measure camera resolution, manufacturers made up their own formula to make their cameras sound a little bit more appealing. For instance, if you were to truly test a 700TVL camera using a resolution chart, you would find that it can actually only decipher 525 TV Lines. Here’s how the manufacturers turned 525 into 700 magically:

525 (actual readable TVL) ÷ 3 x 4 = 700TVL

Using this “creative math,” that 1000TVL camera would really be a 750TVL camera. But since Analog DVRs max out at 720TVL anyhow, nothing beyond that matters.

This chart is used to test the resolution of TVL cameras.  Most 700TVL cameras can only decipher up to 525 TV Lines. This chart is used to test the resolution of TVL cameras. Most 700TVL cameras can only decipher up to 525 TV Lines.

Make Sure It’s HD

The best way to ensure that you’re getting a High Definition camera is to avoid any camera that uses “TVL” as a way of measuring resolution. The true HD resolutions are 720p, 1080p, 4 Megapixel, and 4K (8 Megapixel).

Security camera systems that use Cat5 or Cat6 ethernet cable are always going to have the best resolution. If you are setting up a new system, you should be looking at IP cameras that use Cat5 cable and Power Over Ethernet. This is another way to be sure that your cameras will record in HD.

This doesn’t make cameras that run over Siamese Coax cable and BNC connectors completely obsolete. There are certain technologies that can record decent High Definition using those old “analog cables.”

If you are looking to upgrade an old Analog CCTV System to HD and use the same cables, you should look at a true HD over Coax technology like HD-TVI. Keep in mind that an HD-TVI camera will only get you HD resolution if you have an HD-TVI DVR as well, meaning that you cannot connect an HD-TVI camera to an Analog DVR.

The point of this article is to show that numbers and marketing terms can be misleading to shoppers. Do your research and understand the product that you’re purchasing. For more information on how to decipher Resolution measurements, as well as an extensive comparison to Analog vs IP, check out this article.