Security Cameras FAQ

• What does Lux Mean?
• What is BLC (Back-Light Compensation)
• What is AGC (Automatic Gain Control)
• What is the running distance of RG59 / RG6
• What lens size do I need for a given angle

• LUX is defined as "Relative amount of light that will produce a viewable image." Cameras actually work in the opposite of the ratings of LUX. LUX is actually amount of light created where cameras are capturing light. Below is a general reference of amount of light created in LUX ratings.
  

  A few LUX ratings for reference

  The sun	100,000
  Sun with light cloud	70,000
  Sun with heavy cloud	20,000
  Home/office lighting	100-1000
  Sunrise/sunset	500
  Street Lighting	1-10
  60 Wt. Bulb 10 ft. away	10
  Twilight	4
  Full Moon	0.2
  Quarter Moon	0.02
  Overcast Moon	0.007
  Clear Night Sky	0.001
  Average Starlight	0.0007
  Overcast Night Sky	0.00005

  {Back to Top}
  

• BLC Many cameras included a BLC circuit. This circuit is used to help correct an image with more light behind the subject being viewed. Without backlight compensation, the subject appears dark with little detail. Using backlight compensation will reduce the brightness of the light to allow the subject to appear brighter and bring out the details.
  {Back to Top}
  

• AGC Most cameras come with an AGC circuit. This circuit examines brightness level of the video signal to keep it at a consistent level. For example, if the video signal is dark, it will attempt to increase the gain to bring the brightness up to a normal level.
  {Back to Top}
  

• Cable Lengths

  Cable Type	Maximum Distance
  RG59/U	750 Feet
  RG6/U	1,000 Feet
  Minimum cable requirements: 75 ohms impedance All-copper center conductor All-copper braided shield with 95% braid coverage {Back to Top}

  
  

• Lens Size

  Focal Length	Angle of View
  2.8mm	97.4 degrees
  4mm	71.6 degrees
  6mm	44.4 degrees
  8mm	34.5 degrees
  3.3-8mm	95.2-35.9 degrees
  5-60mm	53.6-4 degrees
  {Back to Top}

     

  CCTV Camera Systems DISCLAIMER:

  Double Eagle Services, Inc. is not a security services company. We do not supply camera systems for the purpose of third party monitoring or response. Double Eagle Services, Inc. does not offer monitoring or response services. Our systems are Closed Circuit TV systems intended solely for use by the end user for their own monitoring purposes. We recommend that the end user who desires to have third party monitoring or response service to contact such a company.