Guides
Night vision: what the infra-red rating really means
A camera rated for 30 metres of infra-red will show movement at 30 metres but usually gives an identifiable face at only 12 to 15. Infra-red range figures assume a reflective subject in clear air. Plan from the identification distance rather than the number on the box.
Halve the number on the box
Manufacturer IR ratings measure the distance at which something is visible, not identifiable. For planning purposes we use roughly half the rated distance for anything you need to recognise.
Dust and rain eat range
Infra-red scatters off airborne dust, which this district has plenty of. A camera that performs to its rating in January may lose a third of its useful range in a dry, dusty May.
A little ambient light beats a lot of IR
One low-wattage lamp over a gate improves the night picture more than upgrading to a longer-range IR camera, and it costs less. Where you can add light, add light.
Colour at night
Some cameras use a white spotlight to record colour after dark instead of black-and-white infra-red. Colour makes clothing and vehicles far easier to describe, but the light is obtrusive — good on a yard, wrong outside a bedroom window.
How well do CCTV cameras see at night?
Why is my night footage all white in the middle?
Infra-red is bouncing back off something close to the lens — usually a wall, a soffit, dust on the housing, or a spider web. Reposition the camera or clean it. It is almost never a fault with the camera.
Do I need a light if I have infra-red?
Not strictly, but a modest light almost always improves the result and lets you record in colour. Where identifying people matters, light is the cheapest upgrade available.
Need this doing?
CCTV installation covers surveying your premises, choosing camera positions that actually cover your entrances and till, running cable in conduit, fitting the recorder with enough storage for your retention needs, and setting up phone viewing before we leave. A four-camera system typically costs PKR 45,000 to 70,000 installed.
CCTV installation — what it costsRelated pages
Get a free site survey
We walk the premises, mark up a plan and give you an itemised quote in rupees. No obligation to buy from us afterwards.