Here at NetXL we sell a variety of IP CCTV cameras and video surveillance hardware. If you’re considering purchasing a new IP CCTV camera, what should you look out for? We’ve dived into a few aspects such as lens sizes and camera resolutions to provide you with a starting point to how they can play a part in your camera surveillance imaging.
Focal lengths and lenses
The lens size of the camera will help determine the field of view, sometimes known as the viewing angle. The focal length is measured in millimetres and cameras will more commonly come with either 2.8mm, 3.6mm or 12mm lenses. Generally, the smaller the focal lens size, the wider the visible area but with lesser details. The larger the focal lens size is, the further it is possible to see, but narrower the viewing angle. Wide angle cameras can give views of entire landscapes whereas a telephoto lens will offer the option to zoom into small objects in the distance.
Hikvision cameras for example have wide coverage with lenses ranging from 2.8mm - 12mm and 8mm - 32mm, so you may require less cameras to cover a greater area. Cameras with a zoom lens can help you easily move between wide angles and more narrow fields of view depending on your needs. The Hikvision DS-2DE4A225IW-DE IP PTZ camera has a 25x optical zoom lens with 16x digital zoom and a focal length between 4.8mm to 120mm, which actually offers great detail over expansive areas. With Hikvision IP PTZ cameras, it is also possible to use the Hikvision Hik-Connect app to control the zoom of your cameras remotely from your smartphone or tablet.
Aperture sizing controls the amount of light that passes through a camera lens and this is measured in f-stops. The lower the f-stop number, the wider the aperture. The Hikvision DS-2DE4A215IW-DE IP camera comes with an aperture range of f1.6 to f3.5 to offer visibility in high and low light settings.
The aperture can also have an affect on the depth of field of a surveillance camera for example the sharpness between the nearest and farthest objects in a scene. A narrow aperture will offer a large depth of field which can ensure more objects are captured in focus.
Generally with IP CCTV cameras, a larger number of megapixels offers the potential for better image resolution. This ensures better clarity and finer imaging when zooming into recorded footage whether this is via an IP PTZ camera or an ANPR camera such as the Hikvision DS-2CD4A26FWD-IZS-P.
Resolutions range from 720p (1280 x 720 pixels) and 1080p (1920 x 1080 pixels) which is classed as a High Definition (HD) resolution. Low pixel resolutions can be useful where bandwidth is limited, but IP cameras will mostly offer at least 1280 x 720 pixels. Higher megapixel resolution offers flexibility when working with different width to height aspect ratios.
IR (Infrared) night vision, inbuilt technology such as Hikvision’s Darkfighter low light technology can all affect the image quality, along with sensor types. You may have come across 1/2″, 1/3″, 1/4″, 2/3″ image sensors before, with the smaller sensor number equating to a narrower field of view.
You can compare all the specifications and features of our Hikvision cameras range on our dedicated IP CCTV camera pages.