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Unread 12-03-2012, 23:55
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Re: Blue or Red colored LEDs causing problems?

We use red LED's, but because of the nature of the retro-reflective tape and that of the Axis cameras, the rectangle returns as pure white. to process this, we use a gray scale image and identify the rectangle by the intensity of the light. This is an effective and efficient means of target identification.
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Unread 13-03-2012, 00:23
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Re: Blue or Red colored LEDs causing problems?

I think that your problem may have to do with field lighting interference. My team has had problems with lighting interference from the field lights. We are using green LEDs. Some people posted on my thread and recommended infrared LEDs, since the field lighting probably won't interfere with the IR light.
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Unread 13-03-2012, 08:28
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Re: Blue or Red colored LEDs causing problems?

You guys know that due to the nature of the retro reflective tape, only light coming from your robot or directly in front of or behind your robot or the target is actually reflected back to your camera? The reason green LEDs work so well is human vision is more sensitive in the green spectrum so the camera is more sensitive in that area to mimick human vision.
If you are receiving a white image of the target, it is possible you are receiving so much light from the tape that the camera is actually white clipping the video. White clip prevents output video from exceeding a certain value and so additional light causes all three colors to "clip" off the top and return a monochrome signal above that level. The result is a zero chroma signal during that interval.
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