A129 CPL Filter?

_Bryan

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I just received my A129 filter and I thought it would at least make a little difference with glare. Here are pictures with and without the filter and I don't really see any difference except that the filter makes the picture slightly darker. I tried putting the filter on the opposite way (putting the side that was down at the top).

I did see a video showing that when you turn the filter 45° to the right it should block out the the A129 screen to show it works, and it does do that. Any idea on how to get the filter to actually reduce the glare?

No filter on TOP - Filter on Bottom
No Filter.jpgWith Filter.JPG
 
the closer the camera to a windshield - the less reflection.
the lower the camera on a windshield - the less reflection.
there should be no dashboard visible on a picture and a minimum of the hood.
try it.
 
the closer the camera to a windshield - the less reflection.
the lower the camera on a windshield - the less reflection.
there should be no dashboard visible on a picture and a minimum of the hood.
try it.
That's a misconception.

See this: https://dashcamtalk.com/forum/threa...n-the-right-cameras.20413/page-10#post-277887

As to the amount of dash/hood in the frame it's generally recommended about 40% sky and the rest being whatever it is. Too much sky and you start having some significant exposure issues. This has to be tempered a bit by the color of the vehicle's hood, how individual cameras handle exposure, and how localized the exposure can be controlled (center weighted, full screen, low cut, etc.).
 
the closer the camera to a windshield - the less reflection.
the lower the camera on a windshield - the less reflection.
there should be no dashboard visible on a picture and a minimum of the hood.
try it.

I am using the supplied mount for the camera, so I have no idea on how to get it closer to the windshield.
The camera is currently up kind of far to hide behind the black grid. I would not want to lower it below the bottom of the mirror. Would that 1 or 2 inches make a big difference?

Mounted.jpg

I just tried a few different shots with less hood, but the sun was in a bad spot and I could not really tell if it was better. So I will try again tomorrow.

Most of what I have read says more hood than sky is usually the best. But I guess that will also depend on who you talk to.

Thanks for the help.
 
That's a misconception.

See this: https://dashcamtalk.com/forum/threa...n-the-right-cameras.20413/page-10#post-277887

As to the amount of dash/hood in the frame it's generally recommended about 40% sky and the rest being whatever it is. Too much sky and you start having some significant exposure issues. This has to be tempered a bit by the color of the vehicle's hood, how individual cameras handle exposure, and how localized the exposure can be controlled (center weighted, full screen, low cut, etc.).
inconclusive.
you use 2 different cameras, different shooting positions and even horizontally the cameras shoot different pictures.
the amount of reflections depends as well on the windshield angle. the more vertical the windshield is the less reflections you should have and on a vertical or side window when the CPL almost touches the window the reflections should be close to nothing.
 
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I am using the supplied mount for the camera, so I have no idea on how to get it closer to the windshield.
The camera is currently up kind of far to hide behind the black grid. I would not want to lower it below the bottom of the mirror. Would that 1 or 2 inches make a big difference?

View attachment 42458

I just tried a few different shots with less hood, but the sun was in a bad spot and I could not really tell if it was better. So I will try again tomorrow.

Most of what I have read says more hood than sky is usually the best. But I guess that will also depend on who you talk to.

Thanks for the help.
I have my camera mounted almost exactly in the same spot. the idea is if you look at it from outside the camera is about on the same horizontal level as the rear view mirror, it still should be somewhat stealthy, right?
 
inconclusive.
you use 2 different cameras, different shooting positions and even horizontally the cameras shoot different pictures..
All true, but the examples I posted in that thread were all taken with the same camera positioned in 4 different locations to show the reflections from each of the different positions. The closer to the glass the more reflections. Not just my findings but the experience of a number of other forum members as well. In other words - very conclusive.
 
All true, but the examples I posted in that thread were all taken with the same camera positioned in 4 different locations to show the reflections from each of the different positions. The closer to the glass the more reflections. Not just my findings but the experience of a number of other forum members as well. In other words - very conclusive.
smile3.gif

we get the reflections because of the space between the bottom part of the lens / CPL and a windshield and the distance from the CPL / lens to a dashboard, that's where the reflections come from.
if you mount the camera at the bottom of your windshield would there be less or more reflection?
 
How close to the glass and the angle of the glass dictates how much reflection you will get, how big the reflection issue is depends on the design of the dashboard
 
I am using the supplied mount for the camera, so I have no idea on how to get it closer to the windshield.
The camera is currently up kind of far to hide behind the black grid. I would not want to lower it below the bottom of the mirror. Would that 1 or 2 inches make a big difference?

View attachment 42458

I just tried a few different shots with less hood, but the sun was in a bad spot and I could not really tell if it was better. So I will try again tomorrow.

Most of what I have read says more hood than sky is usually the best. But I guess that will also depend on who you talk to.

Thanks for the help.
and you mounted your camera as close to the windshield as possible.
a picture below is a snap shot from my driving the other day. the camera mounted and aimed almost exactly as I wanted, and in this picture the camera has a CPL on it:

pic01.jpg

a picture below is from my test recordings from a rear camera mounted temporarily on a windshield, it's hanging on a mount (there was about 15mm or more between the CPL and a windshield), or mounted not as close to a windshield as the other camera that's why you see on a picture a dashboard and a reflection of it, has no CPL on it and aimed not the way it should for an everyday driving:

pic02.jpg

I believe this is your case.
aim the camera so the reflections of a dashboard don't get into a picture:

pic03.jpg
 
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Going back to the original post, I would still expect the CPL to be more effective than that, no matter what the camera angle is.

Have you tried simply holding the CPL in front of you eye whilst sitting in the car, then rotating it to see if there is a better angle?
 
I just received my A129 filter and I thought it would at least make a little difference with glare. Here are pictures with and without the filter and I don't really see any difference except that the filter makes the picture slightly darker. I tried putting the filter on the opposite way (putting the side that was down at the top).

I did see a video showing that when you turn the filter 45° to the right it should block out the the A129 screen to show it works, and it does do that. Any idea on how to get the filter to actually reduce the glare?
That test is not a good one, certainly not with the screen in my A129 which I think is circularly polarised so that you can view it properly while wearing polarised sunglasses.

A better test is to look at an LCD TV through the CPL, normally it should turn the TV image black if you look through it from the same side as the camera and have it turned on its side rather than the normal vertical, exactly the same effect as looking at the TV through polarised sunglasses.

Or as Tony suggests, just hold it up to your eye in the car and see at what angle the reflections disappear - should be when it is the correct way up and correct way around.

What sort of vehicle is it? Certainly seems to be something wrong...
 
you can mount the camera on a dashboard:

pic04a.jpg

the mount is quick made and I couldn't aim the camera higher:

pic12.jpg

and 2 more pics from my trip, driving east:

2018_0927_111254_027.TS_20181012_153149.517.jpg

2018_0927_111254_027.TS_20180928_204219.939.jpg

the video looks better than the pictures..
 
Thanks.

Using those my filter was way off. I just adjusted it and will see what it looks like.
post pictures!
we all learn one from another!
 
That test is not a good one, certainly not with the screen in my A129 which I think is circularly polarised so that you can view it properly while wearing polarised sunglasses.

A better test is to look at an LCD TV through the CPL, normally it should turn the TV image black if you look through it from the same side as the camera and have it turned on its side rather than the normal vertical, exactly the same effect as looking at the TV through polarised sunglasses.

Or as Tony suggests, just hold it up to your eye in the car and see at what angle the reflections disappear - should be when it is the correct way up and correct way around.

What sort of vehicle is it? Certainly seems to be something wrong...

I just adjusted it using the video and picture from DarthMaul's post and I will try and see how the results look tomorrow. It would have been easy for Viofo to either put a slip in the box or print on the box to go to a website to check if the filter is properly aligned. They could even put it on the product page. But hopefully it was just delivered misaligned.
 
It would have been easy for Viofo to either put a slip in the box or print on the box to go to a website to check if the filter is properly aligned. They could even put it on the product page. But hopefully it was just delivered misaligned.
I assume they are still making special batches of the A129 version and one missed the alignment procedure!
Easy to do a quality check before being shipped, just need to run them, or a whole transparent box of them over a sideways on TV and any that are off will be immediately obvious.

If it is still not working, check it against a TV or real reflections as Tony suggested...
 
Here are images with a few different angles after the filter was adjusted. It seems to help more towards the center of the image than the sides. I think I will still try a few things to see if I can get it better. I would like to have more of the dash showing if possible. I might try adjusting it by hand looking through the window to see if there can be any improvement. When I have my sunglasses on that are polarized I do not see any reflection of the dash mat, but that is also at a different angle than the camera.

Since the filter has 2 different lenses, what would happen if I tried adjusting them individually? Would it make a difference? I guess I need to look at how the 2 interact with each other.

2018_1015_164007_090F.JPG2018_1015_164040_092F.JPG2018_1015_164052_094F.JPG
 
Here are images with a few different angles after the filter was adjusted. It seems to help more towards the center of the image than the sides. I think I will still try a few things to see if I can get it better. I would like to have more of the dash showing if possible. I might try adjusting it by hand looking through the window to see if there can be any improvement. When I have my sunglasses on that are polarized I do not see any reflection of the dash mat, but that is also at a different angle than the camera.

Since the filter has 2 different lenses, what would happen if I tried adjusting them individually? Would it make a difference? I guess I need to look at how the 2 interact with each other.

View attachment 42548View attachment 42549View attachment 42550
I would aim the camera even higher.
you record the surrounding of the car not your dashboard or the hood.
smile3.gif
 
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