They are magnetically activated by the bottom of automobiles. I used to do a lot of work for a gated community which included occasionally working hand and hand with the installers of the gate sensors. Many traffic light systems also have a strobe sensor attached to the crossbars to see the emergency vehicles coming and switch the light to green to keep traffic moving when they sense the flashing lights. Oddly I've often wondered if I could trigger them using a speedlight with a snoot on it in the stroboscopic mode to get the light to switch to green. One day I might test that theory but certainly not when cop is around. Paul
Interestingly, the circles are sensors for changing the traffic life...I always thought these were pressure activated...and if a light was taking too long and I could, I'd back up and go over the square of circle again...especially at night.
However!
I have been told and believe that these are actually magnetically activated, that it is the metal in the car over the circle that eventually causes the light to change.
I wanted more lights, I'd wait for the traffic signal to change about a 100 yards away, but there really wasn't as many cars as I wished...also, oddly, I couldn't figure out how to turn on and use live view on the 77D...and I did get out my tripod....at least in part because I shamed myself on the Evening Drive image by noting that I seldom use a tripod...so I pulled it out of the trunk...lol
I need to try this again...with enough lights that they almost form an actual fabric looking effect...
Best Wishes, Traveller
Guest
08-Oct-2017 02:09
Some of the light streaks appear to be segmented. LED flicker?
And what are those circles? From an alien spacecraft? It is LA, after all.
It does....I played with white balance, color tone, color balance to get here...this is a compromise of all three functions...maybe good, maybe bad...but it is what it is....thanks for the advice. Traveller
My favorite also and I like the perspective on this one much better. I’d suggest you experiment with the white balance to move away from the yellow of the HPS street lights. But that may jack with your tail light and blinker colors. Paul