proposed license plate camera hack.

DAP

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Dash Cam
Two Viofo 129 PRO cameras and a Tesla Model 3 4 Channel
I just finished watching this video:

I have an A129 pro (not duo)

The rear camera is available for purchase separately: https://www.amazon.com/gp/B07CT5Q5JY
I wonder if the lens has a standard mount so that it could be replaced with a telephoto lens.

I'd also like to know how the cable is wired. It is a USB mini-B on one end, not clear what is on the other end, but it is not USB A. This is definitely not a standard off the shelf cable. I want to know this because I don't want a 20' loop of cable hanging in my front windshield. I'd want maybe a 1 foot cable between the two cameras. I suppose I could just cut the middle out of the cable and splice it back together.

Ideally there would be some software tweaks. This would work fine as is during the day, but at night one would not want to open up the exposure nearly as much because the license plates are reflective and illuminated by headlights. One would want to expose for the license plates, and let the main camera expose for the scene.

For $60, I'm tempted to just buy one just to see if it can be modified this way.
 
Don't know about the lens but the connector is actually 10-pin mini-B on both ends.

20220903_210015.jpg
 
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As with virtually ALL dash cams and action cams the rear cam would likely use a standard M12 x 0.5 lens, also known as an "S-mount". Early dash cams originally "borrowed' this lens type from the CCTV industry.

What you propose has been done by various members here on the forum with varying degrees of success, although rear cameras can be more challenging to retrofit with aftermarket lenses than primary cameras.
 
Don't know about the lens but the connector is actually 10-pin mini-B on both ends.
If it is 10 pins, it is not USB mini-B, mini-B only has 5 pins.

I did not find the connector at digikey. I did find something I think is correct at AliExpress: https://www.aliexpress.com/item/3256801721928779.html?spm=a2g0o.detail.1000013.1.e502619476zThs&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.300834.0&scm_id=1007.13339.300834.0&scm-url=1007.13339.300834.0&pvid=51c9ce0d-29d2-49b2-ad8b-c8dc7ec9f0dc&_t=gps-id:pcDetailBottomMoreThisSeller,scm-url:1007.13339.300834.0,pvid:51c9ce0d-29d2-49b2-ad8b-c8dc7ec9f0dc,tpp_buckets:668#2846#8113#1998&pdp_ext_f={"sku_id":"12000018083840207","sceneId":"3339"}&pdp_npi=2@dis!USD!0.9!0.71!!!!!@210323b216623193934786962e8074!12000018083840207!rec

Shipping is more expensive than 5 connectors.

Still leaves the question of how is the cable built? Given that this is video, the cable either contains twisted pairs, or coax, and one must know which pins pair together for the cable to work.

Looks like Viofo sells the cables separately. The shortest they sell is 80 CM (a bit less than a yard). Not quite as short as I want, but much more manageable. https://viofo.com/accessories/93-69...63-used_for-a129_duo_a129_duo_ir_a129_pro_duo
I found a shorter cable from a different brand: https://www.amazon.com/gp/B07RG7LWG6
Once you figure out how Amazon has classified S-Mount lenses, they have lots to choose from: https://www.amazon.com/s?k=Surveillance+Camera+Lenses&rh=n:14241451&ref=nb_sb_noss

I think I will go ahead with this. I just hope the rear camera is assembled with screws, and not glue.
 
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If it is 10 pins, it is not USB mini-B, mini-B only has 5 pins.
That's not correct.

@Nath has got it right, 10 pin USB-A to Mini-B cables are indeed available. 8 pin USB-A to Mini-B cables are available as well.

https://www.amazon.com/gp/B06XG1J9CY

10pinusb.jpg


8pinusb.jpg
 
10 pin or 8 pin mini-B connectors are not part of the USB standard, some of them may be compatible, but they are proprietary cables.
 
But, you said "mini-B only has 5 pins" yet 10 pin mini-B does indeed exist. @Nath even posted a photo of one. These mutiple pin USB cables have been around for many years and they have primarily been associated with different types of cameras along with certain peripherals . Claiming they are "not part of the USB standard" is simply moving the goal posts. It is irrelevant if they are proprietary as long as you can order one for your needs.

short Viofo A129 Series rear cable:
 
As with virtually ALL dash cams and action cams the rear cam would likely use a standard M12 x 0.5 lens, also known as an "S-mount". Early dash cams originally "borrowed' this lens type from the CCTV industry.

What you propose has been done by various members here on the forum with varying degrees of success, although rear cameras can be more challenging to retrofit with aftermarket lenses than primary cameras.
I noticed that your Mobius varifocal conversion made the video :cool:
 
I noticed that your Mobius varifocal conversion made the video :cool:

Yours too! :)

And unlike in almost every other similar circumstance I was pleased to see that @Vortex Radar acknowledged the source with a credit and tagged us for a heads-up. My typical experience has usually been that people just appropriate some of my content for their own purposes and then sooner or later I stumble upon it somewhere. Happy to see someone with some ethical standards. :happy:
 
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But, you said "mini-B only has 5 pins" yet 10 pin mini-B does indeed exist. @Nath even posted a photo of one. These mutiple pin USB cables have been around for many years and they have primarily been associated with different types of cameras along with certain peripherals . Claiming they are "not part of the USB standard" is simply moving the goal posts. It is irrelevant if they are proprietary as long as you can order one for your needs.

short Viofo A129 Series rear cable:
My goal posts have never changed. If it is not covered by the USB standard, it is not a USB cable. At best, it is a cable that is compatible with USB. There are certain requirements that must be met to put the USB logo on a product. If it does not have that logo, it is definitely not a USB cable, but many vendors put the logo on the products when they should not.

The USB.org website has approximately 250 specifications listed: https://www.usb.org/documents?search=&items_per_page=50&page=0 I have not read all of them. It is quite possible I am wrong, but you will need to find where in which specification extra pins are allowed on a mini-B connector before I will accept that. You seem to have the energy for that, so have at it.
 
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My goal posts have never changed. If it is not covered by the USB standard, it is not a USB cable. At best, it is a cable that is compatible with USB. There are certain requirements that must be met to put the USB logo on a product. If it does not have that logo, it is definitely not a USB cable, but many vendors put the logo on the products when they should not.

The USB.org website has approximately 250 specifications listed: https://www.usb.org/documents?search=&items_per_page=50&page=0 I have not read all of them. It is quite possible I am wrong, but you will need to find where in which specification extra pins are allowed on a mini-B connector before I will accept that. You seem to have the energy for that, so have at it.

Who the hell cares about "USB standards or "guidelines" or "logos". That's all irrelevant and the reason I feel you're moving the goalposts. Your stated "goal" was to find out what kind of lens mount the rear camera on a A129 Pro requires so you might add a telephoto lens to it and you wanted a short rear camera cable so you could mount it to your windshield. I provided you with answers to both of those questions including a link to an 80 CM version of the rear camera cable directly from Viofo.

Methinks you prefer to argue rather than see if you can get the concept to work.
 
Who the hell cares about "USB standards or "guidelines" or "logos". That's all irrelevant and the reason I feel you're moving the goalposts. Your stated "goal" was to find out what kind of lens mount the rear camera on a A129 Pro requires so you might add a telephoto lens to it and you wanted a short rear camera cable so you could mount it to your windshield. I provided you with answers to both of those questions including a link to an 80 CM version of the rear camera cable directly from Viofo.

Methinks you prefer to argue rather than see if you can get the concept to work.
While you did provide me with the name of the mount (thank you for that), I was the one who found the link for the 80CM version of the rear cable on my own, and the even shorter one from a third party. You can go back through this thread to see that if you don't believe it.
I care about USB standards, as does the USB Implementers Forum, and anyone who has ever had to deal with a phony USB device. You not caring is irrelevant.
As far as being argumentitive, it takes two to have an argument :)
 
I care about USB standards, as does the USB Implementers Forum, and anyone who has ever had to deal with a phony USB device. You not caring is irrelevant.

So if, as you claim, 10 pin mini-B USB cable plugs do not adhere to the "USB standard" why are you OK with the one from Viofo? According to what you say, it too must be proprietary and therefore not compliant with the standard. You can't have it both ways. Must be a "phony USB device", apparently. :rolleyes:
 
So if, as you claim, 10 pin mini-B USB cable plugs do not adhere to the "USB standard" why are you OK with the one from Viofo? According to what you say, it too must be proprietary and therefore not compliant with the standard. You can't have it both ways. Must be a "phony USB device", apparently. :rolleyes:
Because It is connecting two parts of a camera system together. It is a proprietary cable for a proprietary purpose. I do not believe that you can hook up the rear camera to a computer via a USB cable and expect it to work. It is not a USB device.
In the future, I will be ignoring this discussion as it is irrelevant to the purpose of this thread.
 
Update: I have received the reverse camera and successfully non-destructively disassembled it.
The outer case is held together by 4 screws.
The moving part of the case is snapped together. I was able to get it apart without snapping off any of the latches.
The original lens is glued into the threaded mount, but the glue can be chipped off to free it up.
The original lens comes with an IR cut filter as part of the lens. The lens I purchased does not have an IR cut filter. I don't think this will be an issue. The color will be wrong, but light sensitivity will be higher, and all I want it to do is read plates.
There is a problem however the lens, having a longer focal length, does not focus until it is about half a millimeter beyond the end of the mounting tube.
I looked on amazon for a replacement mount, but the mounting screws on this one are 19mm apart, and the only ones available from Amazon are 18mm, or 20mm.
I have a work around in mind. I can cut a spacer out of aluminum and insert it between the circuit board and the lens mount. This will take a bit of time. but it will move the end of the mounting tube further away from the sensor, allowing the lens to be mounted. There appears to be plenty of space in the plastic housing to allow that.
 
It is a proprietary cable for a proprietary purpose. I do not believe that you can hook up the rear camera to a computer via a USB cable and expect it to work.
Again, who cares! You didn't buy the cable to hook it up to a computer, you bought it to work with a camera. That's what these type of cables are for. This whole business of "USB standards" is nothing more than a red herring in this particular situation.
 
Update: I have received the reverse camera and successfully non-destructively disassembled it.
The outer case is held together by 4 screws.
The moving part of the case is snapped together. I was able to get it apart without snapping off any of the latches.
The original lens is glued into the threaded mount, but the glue can be chipped off to free it up.
The original lens comes with an IR cut filter as part of the lens. The lens I purchased does not have an IR cut filter. I don't think this will be an issue. The color will be wrong, but light sensitivity will be higher, and all I want it to do is read plates.
There is a problem however the lens, having a longer focal length, does not focus until it is about half a millimeter beyond the end of the mounting tube.
I looked on amazon for a replacement mount, but the mounting screws on this one are 19mm apart, and the only ones available from Amazon are 18mm, or 20mm.
I have a work around in mind. I can cut a spacer out of aluminum and insert it between the circuit board and the lens mount. This will take a bit of time. but it will move the end of the mounting tube further away from the sensor, allowing the lens to be mounted. There appears to be plenty of space in the plastic housing to allow that.

There is obviously quite a lot about aftermarket M12 lenses and modifying dash cams you are not familiar with and many of your assumptions above about how this all works are simply wrong. There's far more involved than just buying a random non-IR corrected lens on Amazon and screwing into your old lens mount. For example, you need to purchase a lens with the appropriate specifications for your project such as one that matches your particular mount, sensor format and such vital key specs as BFL (back focal length). Most people on the forum who strive to do this sort of thing usually ask questions of the many of us who have been doing these sort of camera mods here on the forum for at least the last 8 years or more or they peruse some of the many useful threads people have posted on the subject over the years before they start dismantling cameras and making arbitrary decisions like, "I don't think such and such will be an issue" but that's obviously not your style. Good luck with your endeavor!
 
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The original lens comes with an IR cut filter as part of the lens. The lens I purchased does not have an IR cut filter. I don't think this will be an issue. The color will be wrong, but light sensitivity will be higher, and all I want it to do is read plates.
It is very likely that most of the IR light will be out of focus, and certain that some of it will be, so you probably do want to add an IR cut filter.

There is a problem however the lens, having a longer focal length, does not focus until it is about half a millimeter beyond the end of the mounting tube.
Add an M12 lens thread extender.

I can cut a spacer out of aluminum and insert it between the circuit board and the lens mount.
It will need to be perfectly flat, otherwise you will have focus issues on one side, a thread extender is probably a better choice, less likely to cause focus issues. Also, a conductive spacer may not be a good idea.

you need to purchase a lens with the appropriate specifications for your project such one that matches your particualar mount, sensor format and such vital key specs as BFL (back focal length).
An image is an image, the image sensor just needs an image! If it is a little too big or the wrong aspect ratio, well the edges just fall off the side of the sensor, as they always do anyway since lenses create round images and our sensors are rectangular!
 
An image is an image, the image sensor just needs an image! If it is a little too big or the wrong aspect ratio, well the edges just fall off the side of the sensor, as they always do anyway since lenses create round images and our sensors are rectangular!

You obviously haven't got a clue about this either!

If you want to convert a camera to telephoto you'll want to match your new lens choice's circle of coverage to your sensor size wisely, otherwise you will not achieve the telephoto focal length magnification you are seeking. You'll end up with too much magnification or too little along with possible vignetting. Additionally, you need to purchase a lens with the correct resolving power to match the type of sensor in your camera or you will be disappointed in the performance you achieve. Finally, you need to match your lens' optical specifications to match the lens holder and housing on your particular camera so that you don't end up with the kind of debacle @DAP has created for himself. There are a number of other important considerations in making an aftermarket custom lens purchase as well, especially with telephoto lenses.
 
debacle @DAP has created for himself
So you are 100% certain of that?

I wouldn't recommend trying with the front lens, but it's not too difficult to find a reasonable lens for the rear camera of an A129 Pro, as long as you are not worried about fitting it into the case.
 
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