Hikvision 4MP ColorVu Mini Dome Camera, 2.8 mm Lens, Black, Audio and Alarm DS-2CD2547G2-LS(2.8mm)(C)(BLACK)

What this mini dome is for

A mini dome is a low, compact camera for ceilings and soffits, with the lens behind a clear cover. It sits close to the surface and draws little attention.

This Hikvision model suits a site where the colour of a coat or a car matters after dark, and the installer who needs audio and alarm connections at the camera.

How the camera's technology works

• ColorVu: an F1.0 lens and a high performance sensor gather more light, so the picture stays in colour around the clock. The ColorVu guide explains where it works well.
• White light: when the scene is too dark, the camera uses its white light, up to 30 m. People on site can see this light, so plan where it falls.
• Human and vehicle classification: deep learning sorts people and vehicles from other movement, so alarms can focus on those targets.
• H.265+: a compression method that shrinks video files, so a recorder's drive lasts longer and a network carries less. Actual saving depends on the scene.
• Audio and alarm connections: line in and line out use a two-core terminal block, beside the built-in microphone. The alarm input and output work within the 12 VDC, 20 mA limit.

Where to use it

The IP67 rating and the -30 °C to 60 °C range cover outdoor soffits in UK weather, and IK08 gives protection against knocks. The guide to where to position CCTV cameras helps with the common spots.

The 2.8 mm lens has a horizontal view of 112°, wide enough for a garden, a car park entrance or a shop floor. The black housing blends into dark soffits and frames.

What the figures mean in practice

• 6 m to identify: DORI stands for detect, observe, recognise and identify. At 2.8 mm the figures are 58 m, 23 m, 11 m and 6 m, so mount within 6 m of where faces need to be clear.
• 130 dB WDR: WDR balances bright and dark parts of one picture, which helps where a doorway faces a bright street.
• 0.0005 Lux: lux measures light falling on a scene, and this is an extremely low figure. It is measured @ (F1.0, AGC ON), so real results vary with the scene.
• 2.3 m to ∞: objects from this distance onwards stay in focus, so avoid aiming at something closer that matters.
• Bit rate up to 8 Mbps: higher rates hold more detail but fill storage faster, so set this with the recorder's drive in mind.

Installing it

• Power: use a PoE switch or injector on 802.3af, or run a separate 12 VDC supply to each position.
• Fixings: the DS-1280ZJ-DM46 (Black) junction box is an optional extra that gives the cable joints somewhere to sit. The DS-1276ZJ-SUS (Black) corner mount, DS-1275ZJ-SUS (Black) pole mount and DS-1271ZJ-120 (Black) pendant mount are optional too.
• Aiming: the three-axis adjustment lets you level the picture and set the view after fixing.
• Set-up: configure it in a browser, or through iVMS-4200.

Planning your system

Plan for a network video recorder or a memory card, plus network cable to each camera. Recording sound needs care, and every camera brings legal duties, so read the CCTV rules before going live.

Alarms from line crossing and intrusion detection can notify a surveillance centre or trigger recording. Region entrance and region exiting watch a chosen area in the same way.

Standards and ratings explained

• IP67: dust tight, and protected against temporary immersion in water.
• IK08: a grade of impact resistance for the housing, which helps the camera take knocks.
• Open Network Video Interface: a shared standard that lets network cameras and recorders from different makers work together. The profile letters show which functions are covered.