The differences in diameter of the lens in the security camera determine the angle that can be displayed by the CCTV camera. The larger the diameter of the lens, the narrower and more zoomed in the viewing angle. Most security cameras with fixed CCTV lenses have a 3.6 or 6 mm lens. A 3.6 mm lens is designed to give a viewing angle of 72 degrees. When you need to be able to adjust the viewing angle precisely, it is advisable to choose a security camera with a varifocal cctv lens, because these can be set between often 4 and 9 mm.
Varifocal lens:
Most security cameras that we sell do not have a fixed lens, but an adjustable lens. This has the advantage that the surveillance camera can be used in multiple places and you do not have to make a choice in advance between a number of mm's that the lens must have. Most varifocal lens security cameras that we offer have a lens of 2.8 mm to 12 mm or a lens of 4 to 9 mm and are suitable for most applications and desired film angles.
Below are some sample photos that are made from video images of security cameras with different CCTV lens sizes. All the photos below are taken from images taken by our VGA IP security cameras. 
The photo above was taken from video images made with a 3.6 mm CCTV lens
The photo above was taken from video footage made with a 6 mm CCTV lens
The photo above was taken from video images made with a 12 mm CCTV lens
The photo above was taken from video footage made with a 16 mm CCTV lens
Which cctv lens to choose?
As you can see on the different pictures, the security cameras with a larger lens give a more zoomed-in image. So it is important to check before you buy a security camera if you want more detail or an overview. When you go for a security camera with a varifocal lens, it is possible to adjust the diameter of the lens to your liking and these security cameras are therefore the most flexible.
Of course you can also call: +31 (0) 30-6303631 for advice from the security camera specialist.
View the complete overview of Security cameras here
