In the security field, developers and installers of security and surveillance equipment need to know what, if any, weaknesses their systems have. A blind surveillance camera is useless, and this article offers methods that will blind most current CCD camera offerings.
EditSteps
- 1There are two main conceptual methods of blinding a CCD camera using infrared (IR) light. A popular concept is to fire an IR Laser into the camera, but this has several problems: the camera can see you until you get the laser aimed correctly, you can't see if the laser is aimed correctly, and anything coming between the laser and the camera instantly un-blinds the camera. It also can only blind one camera with one laser, and you might not know where all the cameras are.
- 2The second method is to wear high-brightness IR LEDs. This scales well, allowing occlusion of just the head or the entire person, given enough IR LEDs. The main drawback to this method is that the camera will still know where you are, but it won't be able to identify you. However, it works on as many cameras as are in use, doesn't need to be aimed, and has no on-site setup time. This is the method outlined here.
- 3Decide what level of occlusion you desire. The more the better, but more IR LEDs = more support components = higher power requirements = more batteries used = higher price. The following describes a head system.
- 4Measure and cut strips of support material, each strip about one inch (1") wide and long enough to encircle its part of your head. (Don't remove backing on stick tape)
- 5Eyes: One strip should be covering both eyes, and this is the most important placement area. Each eye should get 4 LEDs, top left bottom right. Once these locations are marked, cut small holes for the LEDs to run through before cutting the eye holes.
- 6Once the eyes are placed, measure, mark, and cut the holes for the rest of the strip at one inch spacing.
- 7Lay the next strip next to the eye strip, measure, mark, and cut holes that are roughly half-way between the LEDs on the eye strip.
- 8Continue this process for the rest of the strips.
- 9Now place an LED into each hole in each strip, aligning them so that the long lead always faces the same way. The long lead goes to positive (+) power through the resistor, the short lead to negative (-).
- 10Group the LEDs into sets of 8, starting with the eyes, keeping each eye in a different group.
- 11Using the heat sink clamps, solder the long leads to the short leads in the groups, leaving the two ends unattached. The top or bottom of the LEDs around the eyes should be an end.
- 12Using the heat sink clamps again, solder the resistors to the long-lead end of each group.
- 13Using the heat sink clamps, solder wires to the short ends of each group, long enough to reach the battery pack. Mark as negative (-).
- 14Solder wires to the resistors on each group, long enough to reach the battery pack. Mark as positive (+).
- 15Wrap all of the exposed leads and wire with electrical tape.
- 16Wrap and secure all of the support strips to the 'inner' cloth.
- 17Wrap the groups of positive wires into one bundle with electrical tape.
- 18Wrap the groups of negative wires into one bundle with electrical tape.
- 19Cut a cross through the center of the eyes in the inner fabric, fold outward and stick between the LEDs.
- 20Cover with the outer fabric, mark the LED locations on the fabric, remove, cut holes for the LEDs, and replace.
- 21Sew the outer and inner cloth to each other between the LEDs. This secures the support material as well, and keeps the LEDs in the holes.
- 22Cut a cross through the center of the eyes in the outer fabric, fold inward and sew to secure.
- 23Cut, even and solder together the positive wires. (now there's one positive wire).
- 24Cut, even and solder together the negative wires. (now there's one negative wire).
- 25Build the battery pack.
- 26Connect the negative end to the negative end of the pack, through a switch if desired.
- 27Connect the positive end to the positive end of the pack.
- 28Test with the test camera. The head covering should look something like the sun sitting on someone's shoulders to the camera.
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