Posts Tagged ‘ infrared’



Common Issues With IR (Infrared) Dome Security Cameras

Written By:
Monday, September 26th, 2011

Common issues with IR Dome Cameras

This is a demonstration of issues you might find with IR Dome Cameras.

  1. If you noticed in this snapshot, you will see white spots around the image. This is caused when the lens is pointed straight up almost at 90 degrees. The lights are OFF and the IR’s are to close to the edge of the vandal dome housing. The light from the IR’s are bouncing back producing this issue.

Figure 1

Demonstration of camera been to closed to the edge of the camera dome cover

Figure 2

To fix this issue you must move the camera lens down to a point that the IR LEDs are not close to the edge of the dome cover. After you have the camera positioned away from the edge of the cover, the image should look like this:

Figure 3

  1. Another issue you might encounter after mounting this type of cameras are smudges and haze in the image. This issue is caused by having finger prints or dirt in the clear cover of the dome camera. This is an example of how it will look like when the dome is dirty:

Figure 4

I will be cleaning the surface of the camera with a microfiber cloth. It is recommended to use this type of cloth to clean the camera, because it will prevent scratches that might cause the IR’s to bounce back.

Right about to clean the camera

Camera image after cleaning the cover

There are many other issues that can cause IR reflection or bounce back. This includes:

  • The dome cover is not bolted in tight enough.

  • The rubber seal between the lens and the dome cover is not flush against the clear dome cover.

  • Another IR camera is in the field of view of this security camera and is causing white out areas.

  • There is a reflective surface above, below or in front of the security camera that is reflecting the IR light back into the camera.


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Dome Security Camera

Written By:
Friday, April 1st, 2011

The dome security camera is one of the most popular types of digital video security camera in use today.  Thanks to modern technological advances a lot of electronic power can be packaged inside a small 3.5 inch diameter dome camera.  Not only are they small and powerful, but the average dome security camera is light weight as well (in most cases weighing just under one pound), which makes it easy to mount just about anywhere.

Today, there are three standard types of digital video camera based on shape; the box type, bullet type, and dome security camera.  How, what, and where the camera is used usually dictates the type, although user preference is also a factor.

Dome cameras originated from their older analog ancestors.  These cameras were often big and bulky and required a great deal more depth than today’s dome security camera.  Often, the older cameras were actually box cameras placed behind a wall or ceiling with the body of the camera extending into the wall space ith just the lens extending through a pre-cut opening.   A glass dome was then fixed over the lens to make it more aesthetically pleasing.  Blackened glass or two-way mirror glass was often used to conceal the lens, so that potential shoplifters, intruders, etc. would not know in what direction the lens was aimed.

Current dome security cameras are nothing like what is described in the previous paragraph.  Considering that the main components of a digital video camera are the lens, the sensor chip, and the Integrated Circuit (IC) electronics the largest part of the camera is often the lens which on the average is about 3.6mm in diameter.

A digital video dome security camera is a compact, highly sophisticated electronic piece of equipment.   The sole purpose of the camera is to transfer light images into electronic images that can be seen on an electronic display device such as a monitor.

It does this by first using a lens to focus the field of view onto a tiny sensor chip.  These chips range from 1/3 inch to about 1/2 inch square.  One of two different sensor ships is used.  Although the chips go about the process differently, both yield the same result; transferring light into electronic impulses that can be measured (and therefore used to create an electronic image).

The sensor chips are either a Charged Coupled Device or CCD or a Complementary Metal Oxide Semiconductor or CMOS.  After the sensor chip converts the light image into an electronic impulse, the IC chips take over processing and digitizing the electronic information and passing it along to the Digital Video Recorder or DVR.

There are several types of dome security cameras based on how they function or where they are intended to be used.  Dome security cameras can be classified as indoor, outdoor, or indoor/outdoor types although most outdoor types today are the combination indoor/outdoor.  Indoor dome cameras are intended to be used inside, under protective cover from the weather and other elements.

Outdoor dome security cameras are protected by an outer shell or case that prevents water, snow, hail, or other damage to the camera itself.   These cameras are often rated according to the International Electrotechnical Commission’s (IEC’s) Ingress Protection or IP standard.   An IP rating of IP55 or higher is usually considered good.

Dome security cameras are usually flush mounted on a ceiling or wall, but may be mounted on special mounts that can range from peduncle type to horizontal extensions.  They require very little surface area for mounting, and can usually be mounted easily using from two to four screws.  The video transmission cable and the power supply cable usually attach from the underside of the mount or there are extensions exiting from under the mount such that the wires remain hidden and protected by the structure the camera is mounted on.

Dome security cameras may also work in InfraRed (IR) modes and the IR Light Emitting Diodes or LEDs are normally clustered right around the camera lens.   This provides directed IR illumination in the exact field of vision of the camera lens.

Security Camera King offers a wide selection of indoor and outdoor (as well as indoor/outdoor) dome security cameras.  Our cameras are of the highest quality and offer the best performance at the most economical price in the industry.

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