CCTV Camera Installation Guide: Types, DVR vs NVR, Storage & Tips

Dome cameras suit indoor ceilings and discreet coverage, bullet cameras suit outdoor walls and long views, and PTZ cameras suit large areas where an operator or preset tour needs to pan, tilt and zoom.

Domes are compact and vandal-resistant, and it's hard to tell which way they're pointing. Bullets are visible — which is itself a deterrent — and typically have a longer infrared range for driveways, gates and boundaries. PTZ cameras cover large parking lots, factory yards and campuses with optical zoom, but they cost more and only see one direction at a time, so they're usually combined with fixed cameras. Turret (eyeball) cameras are a popular middle ground: dome-like, but without the plastic cover that can reflect infrared at night.

Analog HD cameras with a DVR are the budget-friendly option for smaller homes and shops, while IP cameras with an NVR give higher resolution, smarter features and easier expansion for businesses and larger properties.

Analog HD cameras send video over coaxial cable to a DVR, which digitises and records it; each camera usually needs a separate power supply. IP cameras send digital video over network (Ethernet) cable to an NVR, and with PoE (Power over Ethernet) a single cable carries both power and data. IP systems support higher megapixels, better analytics such as line-crossing and people detection, and can reuse existing network cabling.

For most homes and shops, 2 MP (1080p) is the practical minimum, 4–5 MP is a good all-round choice, and 8 MP (4K) is worth it for wide areas where you need to zoom into recordings to identify faces or number plates.

Resolution is only part of the picture. Lens choice matters as much: a wide 2.8 mm lens covers a room but shows faces small, while a 6 mm or varifocal lens gives detail at a gate or counter. A camera placed well with the right lens will often identify a person better than a higher-megapixel camera placed badly. Higher resolution also needs more storage and bandwidth.

Standard CCTV cameras use infrared (IR) LEDs to see in the dark in black and white; colour night-vision cameras use a sensitive sensor, sometimes with a warm white light, to record in colour at night.

IR range is listed on each camera — typically 20–30 m for home cameras and more for outdoor bullets. Colour night vision is useful at gates and parking areas, where the colour of a vehicle or clothing matters. Avoid placing cameras behind glass windows, because IR reflects off the glass and blinds the camera at night.

The recording time you get depends on the number of cameras, resolution, compression (H.264 or H.265), frame rate and whether you record continuously or only on motion.

A simple way to estimate it: daily storage per camera (GB) ≈ bitrate in Mbps × 86,400 seconds ÷ 8 ÷ 1,000. For example, a 2 MP camera recording continuously at around 2 Mbps with H.265 uses roughly 21–22 GB a day. Four such cameras use about 86 GB a day, so a 2 TB hard disk holds a little over three weeks of footage. Motion-based recording, H.265+ compression and lower night-time bitrates can stretch this considerably. Always use surveillance-rated hard disks, which are designed to run continuously.

Almost every modern DVR and NVR supports live and recorded viewing on your phone through the manufacturer's app, once it's connected to your internet router.

Setup involves connecting the recorder to the network, linking it to the app (usually by scanning a QR code), and configuring motion or smart-event alerts. For security, change the default password to a strong one, keep the firmware updated, enable two-step verification in the app if available, and avoid opening router ports unnecessarily.

Wired cameras are more reliable and are the better choice for permanent installations; Wi-Fi cameras are quicker to install and suit a small number of indoor cameras or places where cable can't reach.

Wi-Fi cameras still need power, and their video can stutter or drop when the signal is weak or the network is busy. Many cheap Wi-Fi cameras record only to a memory card inside the camera, which a thief can simply remove. For shops, offices and outdoor coverage, wired cameras recording to a DVR or NVR placed in a secure spot are more dependable.

Cover every entry point first, then the areas where valuables or cash are kept, and position at least one camera to capture faces clearly at head height.

CCTV should protect your property without intruding on others: cover your own premises, avoid pointing cameras into neighbours' homes, and never install cameras in bathrooms, changing rooms or other private spaces.

Businesses should display clear signs that CCTV is in use, restrict who can view and download recordings, and keep footage only as long as it is needed. Recorded video of identifiable people is personal data, so it's sensible to handle it with care in line with India's data-protection law.

Electrons designs, supplies and installs CCTV systems for homes, shops, offices and housing societies across Zirakpur, Panchkula, Chandigarh and Mohali — from a single camera at the front door to networked NVR systems covering an entire building. We visit the site, plan camera positions and lenses, choose between DVR and NVR, size storage for the number of days you need, run neat cabling, set up remote mobile viewing, and offer maintenance, footage-backup setup and AMC, with 24/7 emergency call-outs. If you're securing a property in the Tricity, we'll help you get footage that's actually useful.