Is this footage blurry?

[Dashcamuser567]

Part of my A129 maintenance I took out the card and exported the last 20 videos. I watched some random ones out of those 20 to make sure its recording and everything looks good, but I notice that the video looks blurry?

2019_0621_135615_099F - Streamable

Check out this video on Streamable using your phone, tablet or desktop.

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Is it because of the heat? I had the AC on but when I pulled the sd card it was pretty hot

 

[gse]

No access.
Put the original video on file sharing.

 

[DT MI]

Something is definitely out of kilter. Dash vents are in sharp focus but further out objects are not. Don't know what the cause is but somethings not right.

Separately, you might want to consider aiming the camera a bit higher. You have about 20-25% sky whereas most aim for 40-50%. It will make for more consistent expose but has nothing to do with the focus.

 

[Dashcamuser567]

Something is definitely out of kilter. Dash vents are in sharp focus but further out objects are not. Don't know what the cause is but somethings not right.

Separately, you might want to consider aiming the camera a bit higher. You have about 20-25% sky whereas most aim for 40-50%. It will make for more consistent expose but has nothing to do with the focus.

Gotcha, Ill move the camera up a click to get a bit more sky. I aimed it down back when i installed it since a alot of people had dash cams basically aimed at the sky with only 1/3 on the road. You couldn't even see the hood.

As for focus, Il recheck new footage when it cools down. I think maybe the heat messed up focus? Idk if thats a thing but I saw a video once where a guy put a dash cam in the oven to test heat ratings and the video got blurrier

 

[kamkar]

Heat can make a lens shift focus, and then later when temperatures have dropped it can be back to normal, if the focus remain off you can refocus the lens if you are brave / skilled enough to take the camera apart.
Do seem like the camera have shifted to near focus, which are most often the way lenses go when they go out of focus.

 

[mollydog]

For what it’s worth, with my untrained eyes, looks like the lens isn’t focused on infinity (might be due to heat expansion or just bad focus)

not teaching you how to suck eggs, but with any fixed focus lens, if the infinity is in focus then (all things being equal) depending on focal length / angle of view of your lens everything from infinity down to X (X = equals your lenses closes focus point) should look to be in focus (at a given lens aperture)

looking at your clip and taking in to account you were on the move, I noticed that road signs / road side letter box came in to focus at approximately the same distance from you/your DVR

here is road side letter box

1,



2, a bit nearer and a bit sharper



a closer crop

1, getting in to focus



2, in focus




3, looking sharp



now the first road sign

1,



2, the writing is starting to get in focus



3, you ca just about make out the text



4, now the text is hitting you in the face and can count the flies sitting on it (well maybe not the flies)




1, now for another similar sign and at the given distance no sharp text



2, and as you get to that 4 to 5M from the sign it gets sharper



3, and from 2 to 3M it clear



these are my unqualified opinions that the lens might not be in focus at infinity (this might be due to heat expansion)

this isn’t taking in to account with your windscreen, DVR movements and vibrations and reproducing a still frame from a movie clip

all things will expand and contract with heat but maybe a better polymer that can withstand better temperature fluctuations should be used in the lens mount so once focused, the lens mount can withstand ambient temperature variants with little or no expansion / contraction

 

[gse]

What did you do with your video ???




Can you upload the original video without cutting and encoding? to any Dropbox file sharing service, Google Drive ......
To understand where the problem is.
Give a link to the forum.
Set the settings:
1920 * 1080 30 fps
Expo - (- 1/3)
High bitrate
The angle of the camera head you have is good, but you can slightly lift and see how much the sky will be.

 

[Dashcamuser567]

What did you do with your video ???

View attachment 46852


Can you upload the original video without cutting and encoding? to any Dropbox file sharing service, Google Drive ......
To understand where the problem is.
Give a link to the forum.
Set the settings:
1920 * 1080 30 fps
Expo - (- 1/3)
High bitrate
The angle of the camera head you have is good, but you can slightly lift and see how much the sky will be.

Sorry for the late reply: Here is the link to google drive direct out of dash cam: https://drive.google.com/file/d/14l5kRxqQlE-2JbakfWrJagQ8KnM6vb7V/view?usp=sharing

 

[Dashcamuser567]

For what it’s worth, with my untrained eyes, looks like the lens isn’t focused on infinity (might be due to heat expansion or just bad focus)

not teaching you how to suck eggs, but with any fixed focus lens, if the infinity is in focus then (all things being equal) depending on focal length / angle of view of your lens everything from infinity down to X (X = equals your lenses closes focus point) should look to be in focus (at a given lens aperture)

looking at your clip and taking in to account you were on the move, I noticed that road signs / road side letter box came in to focus at approximately the same distance from you/your DVR

here is road side letter box

1,



2, a bit nearer and a bit sharper



a closer crop

1, getting in to focus



2, in focus




3, looking sharp



now the first road sign

1,



2, the writing is starting to get in focus



3, you ca just about make out the text



4, now the text is hitting you in the face and can count the flies sitting on it (well maybe not the flies)




1, now for another similar sign and at the given distance no sharp text



2, and as you get to that 4 to 5M from the sign it gets sharper



3, and from 2 to 3M it clear



these are my unqualified opinions that the lens might not be in focus at infinity (this might be due to heat expansion)

this isn’t taking in to account with your windscreen, DVR movements and vibrations and reproducing a still frame from a movie clip

all things will expand and contract with heat but maybe a better polymer that can withstand better temperature fluctuations should be used in the lens mount so once focused, the lens mount can withstand ambient temperature variants with little or no expansion / contraction

I checked the quality from an overcast day and it was a bit better so I will probably attribute it to heat causing the issue.

 

[gse]

Sorry for the late reply: Here is the link to google drive direct out of dash cam: https://drive.google.com/file/d/14l5kRxqQlE-2JbakfWrJagQ8KnM6vb7V/view?usp=sharing

Focus shot down.

 

[Dashcamuser567]

Focus shot down.

Due to heat?

 

[gse]

Due to heat?

I can not confirm it or extinguish, it is necessary to check.
How to check the defocus:
Put a cold DVR to record a static image after, 30 minutes we compare the first cold freeze and the last hot, if the focus floats it will be visible.
All Viofo recorders put metal holders and problems with defocus should not be.
What could be:
Poor adjustment of the lens at the factory,
And my guess is:
the metal holder has a short threaded part where the lens is screwed in, until the correct alignment it is screwed literally into two or three turns of the thread, then fixed with a back nut and glue, and so due to the small penetration of the lens thread into the holder, the fixing adhesive mass during heating moves the lens to micron fractions in the holder, which is what causes defocusing.

 

[DarthMaul]

I can not confirm it or extinguish, it is necessary to check.
How to check the defocus:
Put a cold DVR to record a static image after, 30 minutes we compare the first cold freeze and the last hot, if the focus floats it will be visible.
All Viofo recorders put metal holders and problems with defocus should not be.
What could be:
Poor adjustment of the lens at the factory,
And my guess is:
the metal holder has a short threaded part where the lens is screwed in, until the correct alignment it is screwed literally into two or three turns of the thread, then fixed with a back nut and glue, and so due to the small penetration of the lens thread into the holder, the fixing adhesive mass during heating moves the lens to micron fractions in the holder, which is what causes defocusing.

View attachment 47529

Seems like a pretty good technical explanation to me.