- 1 How do I choose a CCTV lens?
- 2 What is the difference between a 2.8 mm and 4mm lens?
- 3 What is the difference between 2.8 mm and 3.6 mm lens?
- 4 What does a 2.8 mm lens mean?
- 5 How is CCTV coverage area calculated?
- 6 Which type of CCTV camera is best?
- 7 How far can a 12mm lens see?
- 8 What is a 90 degree viewing angle?
- 9 What is the range of a CCTV camera?
- 10 Which CCTV camera is best suited for wide angle area?
- 11 How far can a 2.8 mm lens see?
- 12 What are the sizes of lenses that are used in CCTV?
- 13 What does lens mean in CCTV?
How do I choose a CCTV lens?
If you have security camera in the office or home and you want to see as much as you can, you should go for 2.8 or 4 mm lens (makes a wider view). If you want to observe a limited area, like an entrance you should go for 6mm or 12mm (makes a narrow view and objects are closer).
What is the difference between a 2.8 mm and 4mm lens?
Although it has more clarity at a further distance, the 4mm lens shows a similar scene to the 2.8mm. The main difference is the reduced angle of view which gives the illusion that objects are closer to the camera. A 4mm lens is useful for detection & identification.
What is the difference between 2.8 mm and 3.6 mm lens?
A 3.6mm lens is designed to provide an approximate 78° field of view and is the perfect camera in most CCTV applications. Most people think that a 3.6mm lens won’t show a large field of view, but as you can see from the below images, there’s not a huge difference between a 2.8mm and 3.6mm lens.
What does a 2.8 mm lens mean?
This is the difference in the fixed lenses on the unit. 2.8mm gives you the widest view and is generally the most common, 12mm gives a zoomed in image. So if you are putting the cameras in a tight room go with the 2.8 if you want to see down a long hallway or view far away go with a higher one.
How is CCTV coverage area calculated?
A simplified calculation for 1/4-inch CCTV lens can be made using the following formula:
- W (horizontal width) = (distance) * 3.2 mm / (Lens Focal Length)
- HorizontalAngle= 2 * arctan(SensorSize/(FocalLenght * 2))
- Watch Video Tutorial.
Which type of CCTV camera is best?
Top 7 Types of CCTV Cameras To Suit Your Requirements.
- Dome Camera. The most economical among the lot, Dome camera is the basic type of security camera, which is meant for indoor installation.
- Bullet Type Cameras.
- C-mount camera.
- Day/Night CCTV Camera.
- Infrared/Night Vision CCTV Camera.
- Varifocal Cameras.
- Wireless cameras.
How far can a 12mm lens see?
At 12mm you will achieve around a 30° angle of view and identification at around 50 feet. The real trick is that this lens can be set to anywhere between those two different focal lengths.
What is a 90 degree viewing angle?
The 90 ° field of view captures all of the objects but in lesser detail. As you can see in the example images above, the camera with 90 ° field of view captures all 3 objects in the scene, though each object takes up a small part of the camera image.
What is the range of a CCTV camera?
They normally quote two figures, the number of TVL and the IR range. This might be called the night time range. IR range is a largely made up number based around how far away from the camera Infra red light can be detected.
|2.8mm lens||1.5 metres|
|6mm lens||5 metres|
|9mm lens||6 metres|
|12mm lens||7 metres|
|22mm lens||12 metres|
Which CCTV camera is best suited for wide angle area?
Reolink PoE security camera RLC-423 is the best -valued wide – angle outdoor security cameras available on the market with a stunning 95 degrees wide field of view and 4x optical zoom capability.
How far can a 2.8 mm lens see?
In general a 5MP 2.8mm lens will offer you around 105° field of view and a 5MP 4mm lens will offer you an 87° field of view.
What are the sizes of lenses that are used in CCTV?
We most commonly use the 2.8 mm focal length for domestic installations. Customers are generally trying to cover their entire property with 4-6 cameras so the wider field of view is required. Fixed Lens Camera:
|Lens Focal Length||Horizontal Field of View|
What does lens mean in CCTV?
The simplest CCTV lens is a piece of glass (or plastic) to focus the light from the outside world onto the camera’s imaging sensor. This lens ‘ only adjustable mechanism is its focus-ring, part of the barrel body, which you turn until your image is as clear as possible.