• CCTV Lens Field of View Calculator
    Supercircuits lens calculator field of view for CCTV cameras and video surveillance

    Distance to object (ft.)   : 

    Imager Size                      :

    Focal Length (mm)         : 



    FOV Horizontal (ft.)        : 

    FOV Vertical (ft.)              : 


    The field of view (FOV) is the amount of a given scene captured by the camera. It is also referred to as the angle of view or angle of coverage. FOV is determined by three elements: the lens and sensor element within the camera and where the camera is positioned in relation to the scene. A large FOV generally results in the target object being relatively small compared to a camera with a small FOV.

    How to use this tool

    1. Enter your distance to the object in the top field.
    2. Enter the imager size of the camera. The imager size is the opening of the camera. A standard CS mount Box camera is 1/3".
    3. Enter the focal length of the lens. Focal length is the rating of the lens. A typical box style camera lens mount is a 3-12mm. For example, at a 100 foot distance with a 1/3" imager and a 3 mm lens, you will have a horizontal field of view of 160 feet and a vertical field of view of 36 feet.
    4. Click the 'Calculate' button to see the horizontal and vertical field of view.

    Click 'Cancel' to clear all the fields and start again.

    How to read license plates

    Typically you need a horizontal field of view of 10 feet or less to be able to read a plate. Thus, at 100 feet with a 1/3" standard camera, you will need a 50mm lens to get a horizontal FOV of under 10 feet. This doubles to a 100mm lens at a distance of 200 feet and so on.

    Using only two fields

    If you are trying to get a 10 foot Horizontal FOV and you wish to know what size lens you need at a given distance, erase all of the fields. Enter 10 under horizontal FOV, then enter your target distance. Click 'Calculate' and the tool will give you the lens you need.

  • CCTV Storage Calculator

    1. Days of Storage           : 

    2. Number of Cameras   : 

    3. FPS per Camera          : 

    4. Hours per Day             : 

    5. Days per Week            : 





    How to use this tool

    1. Enter the number of days of storage you wish to maintain on the hard drive
    2. Enter the number of cameras on the system (typically 4-16)
    3. Enter the frames per second (FPS) of the cameras. Typically customers choose to record between 7 and 15 FPS. Over 25 FPS is normally considered 'real time' but not needed for most applications
    4. Enter the number of hours that your system will record each day. Using the scheduled recording and/or motion detection can dramatically reduce this time.
    5. Enter the number of days in the week that your system will be operational. Again, scheduled recording will be important here.
    6. The results will be in gigabytes. Note 1,000GB = 1 TB

    Note: Frames per second must be per camera. If your CCTV Video Recorder states it can record 120 FPS and you have 4 cameras, divide 120 by 4 to get 30 FPS per camera.

    Note: This calculator utilizes MPEG4 compression at CIF resolution to make calculations.
    Also, 2-3 FPS will capture activity, but not in real time.

  • NVR Storage Calculator for IP Cameras

    Camera Stream

    H.264 (DVR SYSTEMS)

    Camera Resolution:

    1 Megapixel (1280x1024)
    2 Megapixel (1600x1200)
    3 Megapixel (2048x1536)
    QCIF (176x120)
    CIF (352x240)
    4CIF (704x480)

    Video Quality:


    Average Frame Size:


    Number of Cameras:

      -10  -1  +1  +10 

    Frame Rate per Camera:


    Hours Each Camera Will Record:

      Hours Per Day

    Desired Days of Storage per Camera:

      -10  -1  +1  +10

    Bandwidth Required:

      Per Camera

    Estimated Storage:


    1. 30 frames per second is real time. At 3 - 5 frames per second recording you will not miss any activity (remember this is per second)
    2. It is not mandatory to record in real time unless there are regulatory reasons as in case of government facilities or casinos
    3. Traditional analog cameras record at 1 frame per second

    Use this tool to calculate hard drive storage required for your IP Cameras.

    Note: Additional factors may influence a DVR's hard drive storage capacity as well as the number of days the DVR will store information. Most common are HD compression (codec), resolution, and whether the DVR is set for motion detection.

    Please note: all fields are required.

  • Voltage Drop Calculator

    1. Initial Voltage                              : 

    2. AC / DC                                         : 

    3. Current (Amps)                           : 

    4. Cable Length (ft)                         : 

    5. Cable Gauge (AWG)                   : 


    Results :


    Note: Industry standard is a voltage drop of no greater than 10%.


    Use this handy tool to calculate the DC or AC voltage drop for a length of cable.

    How to use this tool:

    1. Enter the initial voltage. Choose if your system operates on 12V or 24V.
    2. Select AC or DC. Choose which voltage type your system operates. Typically the selection will be 12V DC and 24V AC.
    3. Enter the current of your camera in amps. Note: 1 amp = 1000mA. Thus, if your camera draws 300mA, enter 0.3 into this field.
    4. Enter the distance of your cable in feet.
    5. Enter the size of your cable. CCTV standard is 18 awg.
    6. Click 'Calculate.' Click 'Cancel' to clear the results and start again.

    Example 1

    At 12V DC, a 300 mA camera at 100 feet on standard 18 awg will have a voltage drop of 0.38 volts. Industry standard is +/- 10% which is 1.2 volts. In this example, you are within limits.

    Example 2

    12V DC, 0.8 amps or 800ma (not unreasonable for an IR camera) at a distance of 150 feet on 18 awg would give you a drop of 1.54 volts, which is greater than acceptable limits.

    The way to get around this is to have a shorter cable run, or increase the size of your power wire. In this example, increasing the power wire to 16 awg would decrease the voltage drop to 0.96 volts, which is within limits.

  • Volts / Watts / Amps Converter

    Amps   : 


     Volts    : 


    Watts   : 



    How to use this tool

    Watts = Amps x Volts

    Watts is also known as volt-amps and is typically used in conjunction with AC power circuits. Fill in any of the two fields to find the value of the third.

    Example 1

    You have a 12 Volt power supply that delivers 1 Amp of current. Fill in the Volts and Amps fields to find the Watts.

    Example 2

    The AC 24-40 power supply is a 24V AC power supply that can power up to 40 VA.

    1. Enter 24 under volts
    2. Enter 40 under watts
    3. Click calculate
    4. You get 1.66 in this example.

    Thus, the AC 24-40 can supply up to 1.6 Amps at 24V AC.

  • Compare The Field Of View For Various Lenses

    Use this tool to see how different lens sizes affect the field of view (FOV) of your security camera. Try different scenes to find one that most closely matches your security application.

    Note: A 4mm lens provides the widest FOV and a 60mm (telephoto) lens provides the narrowest FOV.

  • Compare IR And Low Light Technology

    Use this tool to see how different no light and low light camera implementations compare. The use of no IR illuminator, a built-in IR, or an external IR illuminator will have a significant impact on image quality.

    1. Normal light - this shows how the scene appears under regular indoor lighting conditions.
    2. Low light with day/night cam - although this is a day/night camera it does not have IR illumination and needs ambient light to capture an image.
    3. Low light with low lux cam - this image is generated by an extremely low light black and white camera without an IR illuminator.
    4. No light day/night cam with IR illuminator - this day/night camera is in black and white mode with an external IR illuminator next to it.
    5. No light low lux with IR illuminator - this image is from a low light camera using an external IR illuminator.
    6. No light with built in IR - this camera has the IR illuminator built into the camera.
    7. No light with built in IR and IR illuminator - although this camera has a built-in IR illuminator it is also using an external IR illuminator to increase IR strength.
  • Video Frame Rate Comparison Tool

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