Double vision (ghosting) at night through windshield?

[Keith]

Remember that side windows are tempered glass, unlike the front windshield. So that's not a fair comparison.

That's a good thing to point out, and I'm aware of it. It was more of a comparison so people know that it's not my camera lens, or the light, also some people mentioned that it might be visible through any type of glass, so I just wanted to give as close a comparison as I could without driving my second car out there to take a photo through its windshield.

 

[Coolcarx]

From what I can see there is a blurred double on virtually all lights. It's more apparent on horizontal lights. It's kind of like a noise you become accustom to until it stops. It's strange to see headlights above the cars in the distance. Also the faux lights seem to jiggle.

 

[Mark Z]

...In the parking lot lamps, you can clearly see the individual LED bulbs in the lanterns in the reflected images, but the original is a bright blur...

I have clearly seen this as well. IMHO, this is a feature for service companies who change the LED street lamps. As they drive down the highway, they can see what LED has failed.

As drivers, we can use the "feature" to report what individual LEDs need replacement. Let's keep the street lamps running at 100% brightness.

And if you need an excuse to stop looking through the windshield, look at this link found on Drudge. We need a separate thread for this news! Tesla's AP dash display is featured:

Driverless cars could encourage bored passengers to have 'sex behind the wheel'

 

[DuplexDianne]

I for one will try hard NOT to notice since it can't be un-seen...,. Hopefully it won't be an issue for summer deliveries.

In case you haven't seen this video...the effect is well documented in other cars as well.

 

[Roentgen]

I for one will try hard NOT to notice since it can't be un-seen...,. Hopefully it won't be an issue for summer deliveries.

In case you haven't seen this video...the effect is well documented in other cars as well.

Interesting in that refraction was above and BELOW - I think I'm seeing mainly just one ghost image above, possibly two depending on how bright the source is.

 

[vandacca]

Interesting in that refraction was above and BELOW - I think I'm seeing mainly just one ghost image above, possibly two depending on how bright the source is.

From an optics perspective, I was expecting there to be an equal image above and below. I see no reason why there should be only ghosting above the source. I'm interested in hearing if you see it any differently. Hopefully, this hasn't brought your attention to additional ghostly that you now cannot "unsee".

 

[Cloc]

Just to throw my data point into the ring. I get a ghost image at night. Just one that floats above the image in the distance. At first I thought I it was part of the car.

I'm wondering if different people have different reports based on their height and position within the car. It seems to be most prominent for me towards the top visible part of the forward windshield. I've seen this before in thick glass that lays at an angle.

My second thought is maybe their is some dirty film on the glass I need to windex away.

And my vin 51XX picked up four days ago.

 

[Vitold]

JJ Abrams would call it a feature.

 

[thimel]

From an optics perspective, I was expecting there to be an equal image above and below. I see no reason why there should be only ghosting above the source. I'm interested in hearing if you see it any differently. Hopefully, this hasn't brought your attention to additional ghostly that you now cannot "unsee".

From an optics perspective, the ghost image is expected only above. It comes from the way the windshield is slanted. There is a diagram earlier in this thread showing how the light reflects off the glass/air interface that makes it clear.

 

[vandacca]

I think the diagram is in a different thread, but I do recall that diagram, since at the time I was going to mention that it was only half-complete (the bottom reflections were missing), but I thought it was a good enough diagram (simple) to explain the concept and I was trying not to be pedantic.

However, post #31 in this thread shows both upper and lower ghosting. I think it would depend on the angle of the viewer. Most angles would probably make the upper ghosting more predominate, but I suspect that both exist.

 

[ohmman]

I think the diagram is in a different thread, but I do recall that diagram, since at the time I was going to mention that it was only half-complete (the bottom reflections were missing), but I thought it was a good enough diagram (simple) to explain the concept and I was trying not to be pedantic.

I believe this is the post. I'm going to attach the image here as well to keep people from having to search. I don't know if I agree that there should be two reflections. The light reflects only one direction - angle of incidence equaling the angle of reflection minus any distortion from the medium. So I think this should be accurate, but I'm happy to be told why I'm wrong (again).

 

[thimel]

I believe this is the post. I'm going to attach the image here as well to keep people from having to search. I don't know if I agree that there should be two reflections. The light reflects only one direction - angle of incidence equaling the angle of reflection minus any distortion from the medium. So I think this should be accurate, but I'm happy to be told why I'm wrong (again).

Yes, that is exactly the diagram I had in mind.

 

[vandacca]

I'm trying not to be pedantic, but the diagram is not an accurate depiction of the issue. The angle of incidence of the originating ray is probably a little off, but the angle of refraction is likely very misleading. In this diagram, it appears that the angle of the refracted ray is almost 90%. At 90 degrees, I see no reason why it would only reflect up.

Imagine an originating ray coming more from above (e.g. A streetlight versus car headlight). You would have the inverse ghosting (below).

But the point here is that ghosting exists. No point in pulling out the Handbook of Chemistry and Physics to determine the index of refraction/reflection for glass/plastic, measure window thicknesses and angles, calculate refraction/reflection angles, to theoretically prove that ghosting can exist in one or two planes.

Besides, post #31 in this thread clearly shows ghosting above and below.

 

[Skotty]

A little speculation here, not sure if suggested already -- maybe the X windshield is thicker due in part to it's large size, and this is offsetting the ghost images more than would happen in a typical windshield. This could cause them to be more noticeable. Of course, plenty of other possibilities as well, mentioned previously, like related to glass coatings, etc.

 

[Roentgen]

I would have to say post #19 is pretty much exactly what I see. Ghosting above, with at least one clear ghost, possibly two if I stare hard enough. I think those pictures are probably the clearest. #31 has a bit too much star effect to match what I see - I'm not sure if that's due to post-processing, the camera, or whether that windshield is worse than mine.

Back to quibbling: If refraction is above and below, that would imply that some layer bends light greater or reflects light more than some of the other layers (reflection in addition to refraction?). One ghost (or two) in either direction from the source could be explained by the refraction diagram above, where the light gets bounced around before coming out. I'm not sure refraction alone could explain above and below - doesn't make sense to me. But yeah, I DO hope someone whips out a handbook of physics to explain! Physics is Phun!

 

[DuplexDianne]

I'm like many others...waiting anxiously for delivery....

What bothered me during the test drive, hopefully more than this ghosting issue may....is the reflection of the speaker grate onto the interior of the windshield. It was enough to distract me. Hopefully I can tune that out, lol.

Anyone else find this annoying??

 

[vandacca]

What I find most annoying, is the lack of a HUD (Head up display).

 

[aesculus]

I spent some time on a long interstate drive last night observing this trait. First I will state my car does have a bit of it but it did not bother me in the least. Objects straight ahead and within 100 feet or so did not seem to exhibit any or a substantial amount of ghosting to even be noticeable. Lights like streetlights or distant tail/headlamps did show some minor ghosting.

So all in all I am not going to be worrying about this unless for some reason Tesla solves the problem and insists I get a new windshield. Based on the physics involved, I highly doubt they will.

BTW my windows have been Opticoated and not sure if that coating could somehow lesson the issue not unlike optical coatings affect camera lens.

 

[Roentgen]

I'm like many others...waiting anxiously for delivery....

What bothered me during the test drive, hopefully more than this ghosting issue may....is the reflection of the speaker grate onto the interior of the windshield. It was enough to distract me. Hopefully I can tune that out, lol.

Anyone else find this annoying??

Another "didn't notice until I read too much here on the forums" thing.

I'm not the primary driver for my new X - but I've heard no complaints from the wife. As I've mentioned in a different post, though, she didn't notice the ghosting either until I pointed it out to her. Doesn't bother her.

 

[Roentgen]

I spent some time on a long interstate drive last night observing this trait. First I will state my car does have a bit of it but it did not bother me in the least. Objects straight ahead and within 100 feet or so did not seem to exhibit any or a substantial amount of ghosting to even be noticeable. Lights like streetlights or distant tail/headlamps did show some minor ghosting.

So all in all I am not going to be worrying about this unless for some reason Tesla solves the problem and insists I get a new windshield. Based on the physics involved, I highly doubt they will.

BTW my windows have been Opticoated and not sure if that coating could somehow lesson the issue not unlike optical coatings affect camera lens.

I was worried coating the windshield, particularly with a thicker film (i.e. tint) or coating could make the "problem" worse. I mean, it's introducing another gradient for light to reflect/refract through, right? I'd love to hear if someone could post pics of this who has a tinted windshield... please?