Varifocal Bullet Camera

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If you are looking for a digital video security camera that can give you a nice tight video shot, you should consider a varifocal bullet camera. These cameras are economically priced and still provide high definition video images. Unless you specifically buy a vandal proof bullet camera, these should be installed where the risk of vandalism is fairly low because the nature of this camera makes it somewhat vulnerable.

Before you make a major digital video system purchase you should determine if a bullet camera is right for your application. Even more so, you want to make sure that a varifocal bullet camera is right for your application. In this article we'll talk a little bit about the cameras and lens to give you some working knowledge so you can make an intelligent decision about what to purchase.

First, let's begin with the cameras. There are basically three types of digital video security camera based on shape. They are the dome, the box, and the bullet style camera.

Dome cameras are often used indoors or outdoors and are usually mounted to the ceiling or wall. Their spherical bubble-like design ...
... tends to make them less obtrusive than a box or bullet camera. Vandal-proof dome camera's bodies are normally made of steel with a tough Lexan sphere for the camera to see through.

Box cameras are probably one of the most popular types of camera used, even today. Unlike the domes or bullets, box cameras are sold as a basic body with no hardware, lenses, weatherproofing, etc. This allows you to purchase the individual components to fit the situation at hand, ultimately making these cameras very versatile in application.

Bullet shaped cameras are becoming more popular over time. They are built with many features making them very versatile from the start. Bullet cameras are usually built in such a way that they come weatherproofed and with night-time infrared technology. This is one of their best advantages.

However, varifocal bullet cameras do have a down side. These cameras are mounted in such a way that they can easily be repositioned making it difficult to create a vandal proof bullet cameras. On the other hand, if this is not a concern for you, then the bullet camera may very well be your best option for a digital video security system.

The camera lens is responsible for one primary function: It gathers the reflected light from objects in its field of view and focuses the entire field on a sensor chip that ranges from 1/4 inch to 1/2 inch square. We'll avoid a lot of technical lens physics by saying that these lenses can be fixed or varifocal.

A fixed lens has one distinct field of view; the view may be broad or tight depending on the lens. Often times fixed lenses are not replaceable and are part of the integral inner workings of the bullet camera (hence they are often called Board Lenses.) The only way to change the field of view with these cameras is to use another lens, if the bullet camera will allow that to be done. However, since most of the lenses are Board lenses they are not interchangeable.

The solution to the confinements of a fixed lens is a varifocal lens. While a fixed lens has only one focal length, varifocal bullet cameras have a range of focal length, measured in millimeters. For example a varifocal lens may have a range of from 3.8mm to 100mm.

So what does this focal length and range mean? Generally the shorter the focal length the larger wide angle shot that is available. In other words a 3.8mm lens will produce a very wide angle shot. On the other hand, a long focal length indicates a very narrow angle of view. A lens with a focal length of 100mm can produce a very tight shot. Another way to consider this principle is to call a varifocal bullet camera lens a zoom lens. The larger the maximum rating of the lens the greater the zoom capability.

Now if we take a bullet camera and put an adjustable zoom lens on it, we can call this a varifocal bullet camera. Remember that these cameras also have Infrared technology including the illuminating Light Emitting Diodes or LEDs built right in to the camera.

If you need more information or would like to purchase a varifocal bullet camera, contact one of our security experts today and they will be glad to assist you.