Quote:
Originally Posted by Daniel_LaFleur
Wattage is wattage...
As long as it is breakered properly, then electrically it should pass inspection, according to the letter of the rules.
Superbright LEDs put out ~2000mcd (give or take some due to manufacturer and wavelength). 2000mcd, unless put directly in front of the camera (less than 6") does not have enough power to saturate the CCD elements within the camera. In addition, the camera is searching for a particular wavelength, which happends to be very close to one of it's primaries (green). Thus as long as the LED has very little green in it's composite the camera will easily filter it out. In fact, at a distance of more than 6" it will be able to filter it out better than the stadium spotlights.
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Daniel,
I have to caution you, you are mixing apples and oranges here. Wattage is not the issue. 680 volts to exposed skin on students, volunteers and mentors is the issue as well as 680 volts to robot frame when the lamp breaks and the cathode touches the frame. I will grant you it is low current but I bet you wouldn't like it if you touched the exposed voltage. There is a difference between safe primary wiring practices and exposed high voltage.
On the camera, I am speaking from my everyday television experience. Small bright light sources are especially nasty to CCD pickups because the the AGC circuits and other electronics tricks used to get a nice looking picture are confused by bright spots in a normally lit frame of video. There are no optical filters before the pickup so all light reaches the face of the pickup where there are individual pixels for the three colors. Most light sources are fairly broad in their spectrum but LEDs can have some rather narrow bandwidths. A white super bright LED for instance has a rather high peak in the blue spectrum and a rather broad peak in the green. That being said, a small bright light produces a sharp image on the face of the pickup which for a variety of reasons, leaks light through the surface of the sensor and also reflects light on the back of the lens which then in turn sends it back to adjacent areas of the pick up. Besides the effect it has on the pickup, the circuitry used for making video outputs and the adjacent leakage paths, the signal then has a significant impact on white balance and local heating on the face of the sensor. All of these things aggravate the ability of the sensor to determine the presence of the correct color light. Add to that the 60 degree field of view of the lens and you are now producing problems that most teams will not be able to overcome.