Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

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.

share|improve this question
1  
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. –  anna v Jun 21 '12 at 5:56
add comment

3 Answers

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.

share|improve this answer
    
Sorry, the disappearance isn't supposed to be arbitrary. It's suppsoed –  Luboš Motl Jun 21 '12 at 4:38
add comment

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.

share|improve this answer
2  
Maybe the powerline damaged the camera. Do you see similar pictures before the car crossed the line ? –  Frédéric Grosshans Jun 21 '12 at 8:55
    
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? –  Luboš Motl Jun 21 '12 at 13:54
    
@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. –  Emilio Pisanty Jun 22 '12 at 8:46
add comment

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.

share|improve this answer
    
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. –  Luboš Motl Jun 21 '12 at 13:58
1  
Maybe the glitch is some sort of Bayer artifact as discussed here ? We need a CCD camera specialist... –  twistor59 Jun 21 '12 at 15:07
    
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. –  anna v Jun 21 '12 at 15:20
    
Very interesting, twistor. –  Luboš Motl Jun 23 '12 at 8:36
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.