Lens terminology

September 2006 CCTV, Surveillance & Remote Monitoring


Varifocal lenses offer the maximum flexibility for the CCTV installer as they can be adjusted to match the exact scene required by the end user. Once obtained, the view can be fixed by means of the lens locking screws.

IR corrected varifocal

Commonly known as day/night lenses. All of the features of a traditional varifocal lens are available but with the added benefits of IR correction. These lenses are manufactured with a special E.D. glass and lens coating. This combination allows the lens to deliver perfect focus under normal lighting and also under IR illumination.

Fixed focal

Fixed focal length lenses offer the CCTV installer fixed images of a scene. These lenses are an ideal solution when the views are known such as a fire exit door or an entrance foyer.

Aspherical lenses

Aspherical lenses are manufactured to allow more light through the lens for much clearer and crisper images. Because of this they are much better in low light conditions.

Zoom lenses

Zoom lenses differ from varifocals since once they have been set up by the CCTV installer, they will always stay in focus no matter how often the zoom ratio is changed. Zoom lenses give you the ability to view and get close ups of objects to highlight details or identification even when the object is some distance away. These are ideal for covert applications where your camera cannot be installed close to your target.

Mega pixel lenses

The megapixel lenses (high definition) are designed to capture the full resolution of megapixel cameras, providing a high contrast and a sharp picture.

Pinhole lenses

Pinhole lenses for security and industrial applications. The lenses are designed for the highest quality images where the viewing area is no more than a pinhole. The lenses can be used on both colour and monochrome cameras.

Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Why rehearsals and drills for crises and evacuation are so important
August 2019, Leaderware , CCTV, Surveillance & Remote Monitoring, Security Services & Risk Management
The rehearsal of concept (ROC) drill has been used extensively in the military, but is just as important when facing risks in organisations and institutions to protect people on the ground.

Milestone partners prove their skills
August 2019, Milestone Systems , News, CCTV, Surveillance & Remote Monitoring, Training & Education
Within the span of one week in mid-May, the Milestone Learning & Performance group celebrated important benchmarks: 200 000 course registrations and tutorial views, and 10 000 certifications.

ONVIF Hosts 20th Developers’ Plugfest
August 2019 , News, CCTV, Surveillance & Remote Monitoring
ONVIF, the global standardisation initiative for IP-based physical security products, hosted its twentieth ONVIF Developers’ Plugfest in early June in Tokyo.

Licence plate recognition camera
August 2019 , Products, CCTV, Surveillance & Remote Monitoring
VIVOTEK has introduced a new licence plate recognition camera featuring built-in licence plate recognition software and edge-computing capability.

Securing Savannah Hills Estate
August 2019, Rhyco Risk Projects , CCTV, Surveillance & Remote Monitoring, Perimeter Security, Alarms & Intruder Detection
Savannah Hills Estate in Midrand planned a security upgrade which was awarded to Rhyco Risk Projects. The project started in March 2019 and was completed in May 2019.

10 things to consider when shopping for a VMS
August 2019, Genetec , CCTV, Surveillance & Remote Monitoring, Integrated Solutions
Today’s video management systems (VMS) provide a wide range of tools and capabilities that help make security personnel more efficient by allowing them to focus on what really matters.

How far are we really at with artificial intelligence?
August 2019, Axis Communications SA , Editor's Choice, CCTV, Surveillance & Remote Monitoring, IT infrastructure, Residential Estate (Industry)
Justin Ludik unpacks exactly how far AI has come and what it potentially can do for society and more importantly, surveillance.

Enhancing security with AI
August 2019, Hikvision South Africa , CCTV, Surveillance & Remote Monitoring
Hikvision explains how residential estates can revolutionise their security strategies and outcomes with artificial intelligence.

More than simply a camera
August 2019, Forbatt SA, Secutel Technologies , CCTV, Surveillance & Remote Monitoring, Residential Estate (Industry)
With the human element being the weakest link in all security solutions, Hi-Tech Security Solutions looks at the pros and cons of using body-worn cameras in estates.

The importance of effective perimeter security
August 2019, Elf Rentals - Electronic Security Solutions, Stafix , Editor's Choice, CCTV, Surveillance & Remote Monitoring, Residential Estate (Industry)
Protecting the perimeter is critical for any residential estate; how does one go about making sure your perimeter is as secure as possible?