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WHAT ARE FRAMES PER SECOND?

fps(frames per second) the number of still frames (pictures) that give the illusion of motion, which appear in a single second of time.

30fps is considered "Real Time". So for Real Time viewing of your cameras, you need at least 30fps for each camera.

Example: If you have a 4 Camera DVR, you will need at least 120fps, for each camera to be considered real time.

The FBI recommends a minimum of 2 frames per second for effective Video Surveillance.
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WHAT IS A LUX RATING?

Lux (1/10 of a foot candle) is a standardized method by which to measure a security camera's sensitivity to light. The lower the number, the less light it will take to reproduce a clear image. For example: A security camera that sees down to 1 LUX, means it generally has the ability to see an image during early evening hours or just before dusk.

A security camera that's down to .1 has the ability to see an image in let's say, a well lit parking lot. A rating of .05, the ability to clearly view an image in a dimly lit area at night. A .05 image can usually enable a security camera to actually see better than the human eye at night!

Lux and low lighting chart
Condition	Illumination		Details
Condition	(FTCD)	(LUX)	Details
Sunlight Full Daylight Overcast Day Very Dark Day Twilight Deep Twilight	10,000 1,000 100 10 1 .1	107,527 10,752.7 1,075.3 107.53 10.75 1.08	Daylight Range
Full Moon Quarter Moon Starlight Overcast Night	.01 .001 .0001 .00001	.108 .0108 .0011 .0001	Low Light Level Range

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WHICH LENS IS RIGHT FOR MY APPLICATION?

How to select a proper security camera lens in 2 easy steps.

1. Should I use Manual Iris, Auto Iris or DC lens?

You can save money and use manual iris lens only when scene illumination never changes. Example: illuminated store or office.
If the light changes a lot it is recommended using auto-iris.

2. What focal length lens do I need?

Guide: smaller the focal length number => wider is field of view.
If you have security camera in the office or warehouse and you want to see as much as you can, you should go for 2.8 or 4 mm lens (makes wide, somewhat distant view)
If you want to observe limited area, like entrance you should go for 8mm or (makes narrow view and objects are closer).
Give us a call and we can help you determine what security camera lens will best suit your location.
Use varifocal lenses to get flexibility for choosing best field of view.

The CCTV security camera lens chart and field-of-view diagrams are designed to assist you in selecting the right lens size for your application. Please contact us if you require additional information or assistance. Keep in mind all of the security cameras we sell come equipped with lenses that will achieve 95% of your surveillance applications.