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This is a followup to my question:

Cyclist's electrical tingling under power lines

Some users presented a convincing picture that the electric shocks under power lines are primarily from the electric fields, not the magnetic one, because the frequency is just too low, and the body must be considered as a capacitor to estimate the currents etc.

Google Maps just included pretty much all of the Czech Republic to the Street View. That's why I could look at the place where I had felt the electric shocks. First, the mast over there clearly corresponds to 400 kV according to a list of masts (model 8a-3), a pretty high voltage. But it's even more interesting to see what the Google car was seeing in front of itself at the same point where I experienced the shocks.

enter image description here

A pretty nice colorful distortion. It is strongly correlated with the masts so I guess it has something to do with the electric fields, too. Am I right? If I am right, what are the electric fields that may cause similarly strong effects in the digital cameras used by Google or others? There are lots of capacitors in those digital cameras, aren't there?

Why is the ordering of the anomalous colors yellow, cyan, violet (from the top towards the bottom where the treetops and roofs are located)? Is it linked to different capacities or voltages or other electric parameters of the three color-sensitive segments of the digital camera?

A blog URL related to the Street View anomalies in Czechia.

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    $\begingroup$ do you have a view from a larger distance from lines even if not these particular lines? My first guess is that at this distance of about 50 meters, even if the drop of the field is logarithmic, the field at the camera would be too small to affect it. What is strange is that the color effect is not around the lines, but seems to be settling.Mosture settling with excited molecules radiating? //Look at this lightning photo cynical-c.com/2006/10/01/close-up-lightning-picture. $\endgroup$
    – anna v
    Commented Jun 21, 2012 at 5:56

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I don't think these distortions are necessarily caused by the power lines. Going along some way forward on your link, under the power lines and then some more, you get to this image,

enter image description here

which shows the distortion in front of the car over an area far from the power lines, when the car is also pretty far from them.

EDIT: There's also some distortion inside the village, with only low-voltage lines around, which I presume the car passed before the image above (based on the blue signs). Going along that road in the opposite direction to traffic the coverage from that day stops at this crossing (at which the clouds miraculously vanish), and on this one on the other side. (i.e., the cloudy-day coverage is limited to a pretty short, straight stretch of road.)

On the other hand, exploring the sunny side I only found distortion near the power lines.

I also found this halo and this one, which are pretty cool.

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    $\begingroup$ Maybe the powerline damaged the camera. Do you see similar pictures before the car crossed the line ? $\endgroup$
    – Frédéric Grosshans
    Commented Jun 21, 2012 at 8:55
  • $\begingroup$ Very interesting, Emilio, although not a full explanation where the effect comes from. Wow, you got even to the bridge. With bikes, we've been crossing the bridge about 500 times. Isn't the halo just due to some rainbow-like effect on wet impurities covering the camera? BTW Frederic, are you sure in which direction the car was actually going? $\endgroup$
    – Luboš Motl
    Commented Jun 21, 2012 at 13:54
  • $\begingroup$ @LubošMotl: Yes, I suspect the halo's causes to be on the camera optics side, though not necessarily because of water (see 2nd edit). I assumed from the traffic signs, one lone car, and some arrows on the road that the road is single-direction, going west, but you'll know better. $\endgroup$
    – Emilio Pisanty
    Commented Jun 22, 2012 at 8:46
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Power lines do cause corona discharges (power line inspection video), which produce some UV light. If the camera is picking up some UV light that might cause a few dots on the picture.

If you inspect the pictures closer you will notice that the pattern only appears sometimes and only in two of the cameras of the car (the front and the rear facing camera). As the car drives along the pattern appears and is gone again repeatedly. It is hard to imagine an influence on the camera which is so arbitrary.

One possible cause is the grounding of one of the cameras. In the picture you linked the car is right below a power line, so an insufficient grounding could lead to some capacitive coupling to the power line.

Maybe it is just a fluke of the image correction algorithm and the guys driving the car speed up too much for it to compensate.

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  • $\begingroup$ Sorry, the disappearance isn't supposed to be arbitrary. It's suppsoed $\endgroup$
    – Luboš Motl
    Commented Jun 21, 2012 at 4:38
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Just discovered that the link can move around.

As following the power lines does not show this effect, it is not associated with them.

It seems to be associated with a tree line, even a tree.

either:

a) a temporary glitch in the camera program building up the picture, since it is not on all views.

b) Much less probable, somebody had been spraying the trees for something and it is a diffraction pattern from the settling spray.

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  • $\begingroup$ Anna, concerning a), do you believe that some programming glitch creates a nice rainbow correlated with the shape of the tree tops and treating the R,G,B basic colors differently? I personally don't; a destruction of the picture by boxes and noise - or some color-blind fuzziness = would be much more likely. Concerning b), do you believe that in the absence of any fields, the camera sees something completely different than human eyes? Or do you believe that the people saw the color strips above the trees as well? You surely don't! ;-) Everyone would think that we had to be nuked. $\endgroup$
    – Luboš Motl
    Commented Jun 21, 2012 at 13:58
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    $\begingroup$ Maybe the glitch is some sort of Bayer artifact as discussed here ? We need a CCD camera specialist... $\endgroup$
    – twistor59
    Commented Jun 21, 2012 at 15:07
  • $\begingroup$ a) Yes. Digital must have color and pattern recognition different for different colors. Then if it gets out of step it could create such an effect.b) Also yes. After all there are infrared cameras, so they can see different than the eye by construction. It could also be that the camera integrates more than the eye. I give b) low probability. $\endgroup$
    – anna v
    Commented Jun 21, 2012 at 15:20
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This is most likely a combination of lens flare and chromatic aberration , possibly made more intense by an image processing algorithm. Notice that the distortion appears at the boundary between very bright clouds and the darker foreground. If you've ever had a junky digital camera, you may have noticed purple "banding" or "fringing" when an image has high dynamic range (bright sunlight and shadows) - this is likely the same phenomena.

As Emilio points out, the effect is visible away from the transmission lines, but in images with similar lighting conditions and with (presumably) the same camera.

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