Nice shot of the Levittown station and bonus for catching the sharp looking Budd built Metroliner cars in the scene!
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| Posted by K100DS on February 8, 2014 | |
Can anyone explain why the ditch lights are on but the head lights are off? That seems odd.
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I asked a question about that in an Amtrak forum. Actually the headlights and both ditch lights were on. They are all LEDs, so the only thing I can figure is that they either "cycle" like a fluorescent tube or depending on the angle they just don't show in the photos. This happened on the shot I posted from yesterday as well.
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The LEDs do "flicker," but not for the same reason fluorescent lights do. An LED has a maximum current that can be fed into it, and thus a maximum brightness. They can handle higher current, but only if it's pulsed. The result is a greater average brightness, and the pulsing can't be perceived by the naked eye. A camera's exposure time can match that pulsing with a result like what's shown above. The headlights and ditch lights are likely both pulsing, but not in sync with each other.
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