CCTV DEALER IN DINDIGUL
720p cameras usually have a sensor with at least 1.0 megapixels. Pixel resolution is 1280 x 1024 (like the Sony SNC-EM600 1.3 megapixel camera), or it can be 1280 x 800 (like the Axis M3004 1.0 megapixel camera).
1080p cameras have at least a 2-megapixel sensor, and it is considered to be the higher resolution “HD camera”. To confuse us, some manufacturers specify their 3-megapixel or 5-megapixel camera as “1080P” as well.
4K Camera: This usually refers to a camera with over 8 Megapixels of resolution. It has approximately 4,000 horizontal pixels. There is some difference between the definitions of the television industry and the security market. The number of vertical and horizontal pixels and the aspect ratio are defined differently. For example, Axis introduced a camera with 3840 x 2160 which runs at up to 30 fps (which they called Ultra HD). The Sony 4K IP camera has a chip with 4096 H × 2160 V pixels which run at up to 60 fps and conforms to the Digital Cinema Initiative. The Hanwha (Samsung) PNO-9080R has a resolution of 4000 x 3000 pixels. The marketing people call all these cameras “4K”.
There are fixed lenses, variable, and zoom lenses.
Fixed lens, as the name implies, has only one mm or angle setting.
A variable lens can be manually adjusted through a range of angles.
The zoom lens is similar to the variable lens, but it can be controlled remotely. This allows you to adjust the setting of the camera lens from your computer making it very easy to install.
Iris: Iris control adjusts how much light falls on the sensor. There are manual iris controls, DC auto iris, and p-iris lenses. The iris affects the depth of field. The smaller the iris opening the longer the depth of field. When the scene is very dark the lens iris opens and the field of view is reduced. This means some areas that are close or far away are not in focus.
The manual iris is manually adjusted and depends on how much light is expected in the scene. A manual iris lens is usually used with indoor cameras where there is a small light variation.
The DC auto Iris lens is usually used with outdoor cameras. The camera electronics adjust the iris opening depending on how much light it detects. At night it opens the iris and when there is bright sunlight it closes the iris.
P-Iris lenses are similar to the DC auto iris lens, except they add additional intelligence to the lens opening. When the iris is closed all the way, it can reduce the clarity of the image (when used with megapixel cameras). It has to do with the pixel size. A P-iris camera system works with the camera electronics to prevent the iris from closing all the way. On the other hand, when the view is very dark, the camera tries to open the iris to let in as much light as possible. As the iris increases the depth of field is reduced. The p-iris lens prevents the lens from opening all the way and compensates by increasing the camera amplification of the video signal.
IR Corrected Lenses: Lenses bend the light to achieve the right focus and magnification. IR light can bend at a different angle than visible light when the wrong type of glass is used in the lens. IR corrected lens compensates for the focal difference and provides a much clearer image. This is most apparent at the higher resolution. If you plan to use a megapixel IP camera system, then make sure you get the IR type lens.
Focus:
The focus of the IP camera can be adjusted either by manually adjusting the lens or by remotely adjusting the distance between the lens and the sensor (back focus). Lenses can have a fixed focus (that can’t be changed), manual focus or auto-focus. “Back focus” is not part of the lens, but is usually listed with the lens specification. This is a very nice feature that makes installation much easier. The focus can be adjusted at the computer, instead of at the camera. Many of the new Sony and Samsung cameras have this feature.
What is the use of CCTV Cameras?
CCTV cameras have become integral security equipment and are widely used in residential apartments, commercial spaces and even in public places. CCTV cameras are strategically placed to monitor and supervise for security purposes. Some of the most common uses of CCTV cameras are as follows:
- Deters & prevents crime
- Helps in traffic monitoring
- Documenting a visual record of activities for security reasons
- Overlooking highly sensitive areas & chemical industries
- Helps in identifying potential risks or threats
