On this page
01. Quick checks you can do first02. What usually causes it03. When to call a technician04. Parts that fix it05. FAQ
Blurry or foggy CCTV images are mostly caused by dust and spider webs on the lens, condensation inside the housing, infrared light reflecting off a dirty dome or nearby wall, or a lens that has drifted out of focus. Clean the glass gently, remove webs, and check whether the haze appears only at night (IR reflection) or all the time (focus or condensation).
Key takeaways
- Spider webs reflect IR and look like fog at night.
- Dirty domes cause glare at night.
- Condensation means a failed seal.
- Varifocal lenses can drift out of focus.
- Cheap cameras degrade faster in sun and rain.
01Quick checks you can do first
- 01Clean the lensSoft microfibre cloth; no harsh chemicals on dome covers.
- 02Remove websWebs near the lens glow under IR at night.
- 03Compare day vs nightNight-only haze points to IR reflection; all-day blur points to focus.
- 04Check for moistureDroplets inside the housing need resealing or replacement.
- 05RefocusVarifocal cameras can be refocused in the menu or by hand.
02What usually causes it
| Symptom | Likely cause | Fix |
|---|---|---|
| Hazy only at night | IR reflecting off webs or dome | Clean; reposition |
| Blurry day and night | Out of focus | Refocus or replace lens |
| Fog inside the glass | Seal failed | Reseal or replace |
| White wash-out | Facing sun or lights | Reposition, WDR camera |
| Gradually worse | Ageing lens/sensor | Upgrade camera |
03When to call a technician
- Cameras are on high walls or poles.
- You need faces or number plates to be readable.
- Many cameras need cleaning and focus checks.
- You want ColorVu or full-colour night cameras.
Running this across several sites or branches? A Qyvea maintenance contract catches these faults on scheduled visits, with a written report after each one.
04Parts that fix it
05Frequently asked questions
How often should CCTV cameras be cleaned?
Every 3 months in most places; monthly near roads, construction or the coast.
Why is my camera clear by day but foggy at night?
Infrared light bouncing off spider webs, dust or the dome cover. Clean it and check nothing is close to the lens.
Is cleaning part of a maintenance contract?
Yes. Cleaning, focus and recording checks are standard on every visit.
