Security Cameras - Common Image Problems
by Don Stephens
There a lot of things that can go wrong with security cameras. The most noticeable are going to be problems with the image itself. The good news is that identifying the problem isn't as difficult as you may think. For as many things that can potentially going wrong, each one of those problems presents themselves with their own set of unique characteristics.
Sun Induced Burn Out
A common thought among the public is that if a security camera is rated for outdoor use, this means that it's impervious to almost anything. This just isn't the case; you're just going to have to take our word for it. The sun is more than capable of destroying your cameras if you're not careful. Direct sunlight entering your camera's lens will eventually run into your image sensor just beyond that. Over time this will start to create distortions on the glass but this is nothing compared to the effect it has on the image sensor. Before very long, you'll begin to see some pretty awful video degradation; this includes blurriness, changes in contrast, and eventually complete blackout. Of course no one is intentionally pointing their camera into the sun but the sun moves and sometimes in a way that can hurt your camera. Monitoring or reviewing video for the first several days after installation will show you if that camera will need to be adjusted or not. Look for any obvious bright glares. These don't always need to come right from the sun. Highly reflective surfaces are just as detrimental. Wide Dynamic Range (WDR) is not a solution and will not save your camera
There's a general rule among the professionals who actually know what they're doing that says, 揇on't ever mount your cameras to a metal surface.? We're paraphrasing but you get the idea. Surges are really the big reason for this but 揵leeding?electrical currents is the other. Bleeding is usually a result of something being wired improperly and that current is making contact with the conductive surface. That current will move around everywhere is can and eventually travel right into your camera if it's not insulated. If you find yourself unable to mount your camera to anything other than a metal/conductive surface, you'll need to find a solution to the problem to avoid ever having one. Mounting a block of wood to this surface and then your camera to the block is very simple fix for this. Just ensure that no metal on metal contact is being made from the camera to any part of the structure.
Ground loops are complicated are really boring to explain, so we're not going to. Ground loops occur for a few different reasons but this issue will always present itself in the form of horizontal lines running across your screen (hum bars). Faulty power supplies and/or faulty cable are frequent culprits but improper wiring in the home/building is much more common. If you discover that your image problems are related to the power supply or cable, you simply need to swap them out. However, if bad wiring in the structure is found to be the problem, locating it and then having someone fix it is not exactly a quick or cheap fix. This is where ground loop isolators come in. They're simple plug-and-play adapters that attach to the back of your camera and then filter this electrical noise out of your video feed.
NTSC vs PAL
NTSC and PAL are two completely different types of video encoding systems. There's not a lot to say here. Depending on the country you're in, you're going to be using one or the other; the U.S. exclusively uses NTSC. If you find yourself with a product using the contradicting system, it will be blatantly obvious the second you power the camera on. You will notice that you may be able to make out some portions of the image, but most of the screen will covered with black lines that appear to be shaking in place. Your only solution to this is simply to read carefully before purchasing anything. This is one of the risks of purchasing from outside of your own country.
Infrared Cut Filter
If your camera lacks an IR cut filter, you're not going to be able to use it outdoors. This usually isn't a problem or an issue for any professional level security cameras but it's still something to confirm. Your 搒tarter?cameras that cost around $30 or less are where you'll need to be careful. Your issue here will be that your image will appear very bright as if the brightness settings are just way too high; needless to say, adjusting the brightness settings are not going to help if you're completely lacking this piece to the puzzle. While you'll certainly not be able to use them outdoors, also be aware that certain ambient lighting in an indoor environment can also cause a similar effect. In addition to having a major problem with daylight, they also will have a difficult time interpreting Infrared properly in darkness.
There are several things that can go wrong with a power supply but related problems will always appear in your video as 搑olling lines.? These are horizontal lines across your screen that will normally move from bottom to top; lines moving in the opposite are not unheard of so don't rule it out. The image from your camera will remain behind these lines and will not move with them. This can often be confused with the lines you can get from a ground loop problem, but the lines caused by a group loop will remain in a single static position.
In present time CCTV is one of the most important parts of any security system and more and more people are installing this system at their business and homes as well. But we all know that CCTV is electronic equipment and just like any other electronic equipment this system also has some common problem with it. So, if you are trying to know more about these problems, then here are 5 CCTV common problems and how to fix them.
5 CCTV Common Problems & How To Fix It
Blur image in the night: This is a very common problem with almost all the CCTV system that it works perfectly in daytime or in bright light, but if the lighting is dull or it is night time then camera give very blur images. In order to avoid this problem, you just need to back focus your camera and after that you will get crisp and clear image in low light or in nighttime as well. For doing this you need to optimize the focus of your camera for dull light as well by opening the camera iris at its full potential. This back focus adjustment is essential for zoom lenses as well and gives you better pictures while using the zooming of the camera.
Picture not displaying in camera: This is another very common problem in all kinds of CCTV system and most of the time this problem occurs because of loss of power supply. So, if you are using a low-voltage CCTV camera for your CCTV system and you find this problem, then make sure you check the fuse and power supply of your system. If you get any problem with power supply just resolve it and it shall start working again. In case this is not the problem, then you might need to check shorts in the wiring of your cable. For this you can unplug the cable at both end and check it using a meter to identify the problem and if you find the problem then you can replace the cable for it.
Bright spots on the monitor: If you will install your CCTV camera in front of any bright light, then you will surely get this problem on your CCTV monitor. Other than this bright reflection of light from any surface toward the camera can also create this problem. So, if you are getting this problem, then you will need to replace your camera position to avoid the problem. In case you cannot install the camera at any other place then replace your lights so you do not get any bright light or its reflection on your CCTV camera.
Snowy bars on the screen: Many times you can see snowy bars or snowy picture on your CCTV monitor. If your camera cable picks any electrical interference, magnetic signal or radio waves than this problem can appear in your system. For avoiding this problem always use a good quality camera cable that is designed to resist these interfaces. Also, install your cables away from all kinds of electrical or network cable, route because if you will install CCTV cables with these cables, then electrical flux of other cables will create this problem in your system and you will get snowy bars on your monitor.
Identification problems: If you cannot identify a person, vehicle or other object after any incident using CCTV clip, then it is of no use to have the CCTV system with you. Well, it may sound little funny and unbelievable to you, but this is a very common problem in many CCTV systems and many times people realize this problem in their CCTV system only after having any incident in their premises. So, make sure you do a test run at your end with a trial situation and verify you do not have this problem in your CCTV system. In case you have this problem with your camera or system, then you can eliminate the problem by repositioning your camera at a better angle with clear focus on entrance gates and at other necessary places.
So, if you are going to have a new system in your house or office make sure you keep above things in your mind to avoid all the future problems with it. And in case you have any of these common problems in your CCTV system, then you know that you can solve most of these problems easily.
CCTV camera is increasingly being used as a spy camera in surveillance system. Not only for business and office needs, but CCTV camera fits the home purpose for security as well. Such being the case, knowing a few basic tips will help in the easy troubleshooting in case of any simple problems with the working of the CCTV camera installed.
CCTV Camera Troubleshooting Tips
Though technical assistance from experts is advised to rectify problems in the CCTV camera functioning, there are a few simple troubleshooting tips to help in this regard.
1. Picture not Displayed in the Monitor
The most common cause of this problem is the presence of open or shorts in the wiring cable. The best way to set it right is by disconnecting the cable at both ends; followed by checking with a meter.
Another probability is power supply loss; mainly with a low voltage CCTV camera. The power supply fuse and the system mains supply must be inspected for the same.
2. Presence of 揋host Effect?in the Monitor
Reflections of the improperly terminated video signals are seen as ghost images. These are secondary images which cause distorted viewing. The signal has to be either redirected onto another video product or terminated to solve the issue.
3. Darker Foreground in Bright Background
This is caused when a bright spot in the image makes the iris to close or the imager to reduce picture gain. Hence the unlit region appears darker than the rest.
Backlight compensation or reposition camera seems to be an effective alternative to avoid lighting problems of this sort.
4. Smearing of Bright Spots on the Monitor
The light reflected from the scene being viewed is captured by the camera. When the light source is bright, a bright white spot with a vertical line passing through it may be seen on the monitor. It is more common during nights.
Altering the position of the camera so as to avoid bright light in the scene can be the ideal troubleshooting tip.
5. Snowy Picture or Scrolling of Snowy Bars on the Screen
When radio, magnetic or electrical interference signals are picked up by the coax cables, it results in snowy bars.Inexpensive cables most often cause this kind of problems.The cables must be re-routed away from the problematic region. Also, good quality cables must be employed and kept away from the existing mains and data cable routes.
These were just a few commonly encountered issues for troubleshooting the spy camera. It is always advised to seek professional help to solve major issues pertaining to the CCTV camera.