Dual 4k Dash cam.

[Milos7]

Hello all,
I bought VIOFO A129 Pro Duo, which comes with rear camera capable of only 1920x1080 30fps.
I am thinking now that I should return it and buy two VIOFO A129 Pro for $400 and use the second 4k unit in the back window.

Has anyone done this, and can the wiring to power the rear unit from the front be the same USB cable as I did with Pro Duo?
I realize that these would be independent units with Micro SD card in each. My concern is if I power the rear camera from the front camera would it cause any issues?


Thanks

 

[kamkar]

Welcome to the forum Milos.
You can put a single channel 4K camera in the rear window just fine, it is just 1 more memory card to work with in the case of a accident or the routine of looking over the footage now and then to make sure things are hunkydory.
Myself i wouldn't like a big camera like that back there, but if i had a sedan i might think different, but i have a small 5 door hatchback with a almost flat rear end, so people do get quite close.

You can not power the rear camera from the front camera, that connection are only meant to power a meager rear camera that dont do any encoding ASO on its own, so you will have to wire the #2 camera in too
Back in the day when there was very few 2 channel systems i put a 3 way 12 V splitter in the back of my little car as powering cameras in the back with a long USB cable,,,,, well it lost the recording of me getting rear ended.
So better to extend on the 12 V side of things.

 

[Milos7]

Thanks for quick reply kamkar.
I think I would instead use a short mini usb Y cable before the front camera. One end will feed the front cam, and the other end would feed the USB cable run that goes to the back window which I already tucked in nicely. It would be bringing the power only to the rear.

You are bringing up a good point about the size of the 4k camera obstructing the rear view window! Certainly something to consider before purchasing.

 

[CaptureYourAction]

Powering the rear A129 Pro via the front USB cable will likely be an issue due to it's length.

 

[kamkar]

The power supply ( viofo ) feeding the front camera are not geared to pull 2 systems, there rarely are much headroom in these power supplies.
The supplied power supply from Vifo are meant to pull 1 system with 2 cameras, so just 1 SOC doing encoding work for the 2 cameras, i doubt there are headroom to pull 2 systems that granted only do encoding for 1 camera each.

If you are going with long USB cables, you have to be damn sure they are of the best quality with good cobber wires, using a cheap cable with CCA wires ( Cobber Clad Aluminum ) like i did, that is a gamble.

Many newer cars also have a 12 V outlet in the back, but i think these might often be on all the time.

And for sure if you run into erratic camera behavior, the first thing you should do it going all factory with the power supply.
Many have come here with a camera acting strange, and we been several people trying to troubleshoot for several forum pages, and only to then learn that the person is powering the camera from some USB port in the glove box, and these build in USB plugs are often very weak.
Same go for people that in the want to have several things on their 12 V outlet in the dash have thrown out the provided power supply and gotten some cheap multi port charger to use that, so they can power the dashcam charge their phone run their NAV unit and what not.
And it might work and it might not, some of these multi port chargers claim powers they dont really have, and you need at least 2 - 2.5 A for a dashcam, and a steady supply not one that drop if you also connect your phone or earbuds to charge.

It is also easy to get a 12 V plug in the rear, just buy one + a fuse adapter so you can tap into a fuse like i did with my 3 port model ( i tapped into a 30 A fuse ) and then you of course need XX feet of wire to get the plug out back.
O and then you might want to tape the 2 plugs together as they might wiggle apart, i experienced that on my 3 port adapter so i put rubber bands on it and the plugs to hold things together, and that worked just fine.

The one i had under my rear seat was something like this, it even have a 2 A USB A outlet.

 

[Milos7]

Thanks for the replies.
Im not worried about current from the power sources, although it is more than worth mentioning. Main (4k) camera draws a lot more than the supplementing smaller rear cam of the Dual system pair.
I have multiple 2A USBA and USB-C ports in my 2022 Toyota. For the night, I currently replug plug my VIOFO Pro duo into this $130 LiFePO4 power bank which gives me about 50h. It charges during driving very fast (about 15% per 1h of driving which gives 8h of dual camera run time.

My original question was if the rear camera port of the Pro Duo main camera can supply enough current to the same 4k main camera if hooked up instead of VIOFO smaller rear 1080 cam which came in Duo package.

 

[Milos7]

This is the power bank Im using while parked.

GOLABS R150 Portable Power Station, 204Wh LiFePO4 Battery​

So far so good. ​

 

[kamkar]

I dont think it would work, but i am guesstimating here as i dont think it have ever been attempted.
The 4K camera i recon eat a lot more power than just the 1080p camera that originally populate that plug / wire.

Also not syre if overloading the front camera in such a way might kill it ? i am not really that much of a tech wizz to know.

 

[Milos7]

I doubt it too. Im a bit surprised noone has tried it yet as no one offers higher than 1080p resolution rear cam other than Thinkware (1440p) which isn't even 4k, and still costs $500. Thats $100 more than two VIOFO 4k main camera units.
Im tempted to say the least.
Video quality at night of front 4k cam has huge advantage over the rear 1080p cam. Also, I like ability to read license plates a bit further than just 5-10 feet directly behind at night. Forget about reading plates in the adjacent lines with 1080p rear cam.

 

[kamkar]

4K paired with +1080 p, thats right it is indeed rare, there are a few dual 1440p systems out now, and as i do not have anything that can display 4K i am not that much in a hurry to get one,,,,, though in a month or so it do seem like i get a full blown dual 4K system, but it is a hybrid system so in essence just two 4K cameras that sync up and can talk to each other over wifi and BT, and also needing 2 memory cards.

Though just like all other current 4K systems it is made on the same IMX 415 sensor, so no revolution in imagery

 

[Milos7]

Well, its ok if you do not have 4k display. You don't need one. You can just play it on any computer screen with software that can pause, zoom in and give you 1:1 pixel to pixel zoom.
If you watch 4k video fit to lesser resolution display than usually you will get ruined details (such as numbers ad letters on the license plates) because of downscaling. But if you can zoom in to 100% (1:1 pixel to pixel) the downscaling is gone, and you can see a lot better.

I use Movist Pro on Mac comp with screen resolution less than 1920x1080.
Playback of scaled 4k looks pretty messed up if you want to read small signs and numbers. This software easily lets you zoom in while playing back to up to 200%, and pan around the frame. You can even move frame by frame getting the clearest captured moment for resolving area of interest.

I will probably upgrade my rear camera to 4k soon so I can read license plates, and recognize faces much better.

 

[Panzer Platform]

Hello Milos,

I kind of did what you are talking about. I’ll leave a link to a video about it at the bottom.

Back in 2019 I also bought a Viofo A129 Pro Duo. I was very impressed with the front channel 4K, and underwhelmed by the rear channel 1080p. As luck would have it after 21 days the camera overheated, and self destructed. I don’t have any proof but I think the rear channel caused the main camera unit to overheat.

Fast forward to 2020 BlackboxMyCar sent me the newly released A129 Plus Duo for test & review. After testing, I liked it so much I bought a second A129 Plus Duo with my own money. I planned to just use the two front main units to build a 2K 2-channel system, and not even install the rear 1080p cameras.

I had to buy a longer 20 foot mini USB cable for the camera mounted on the rear window, and I run both cameras off the original Viofo dual USB charger. After a few days I figured why don’t I install the rear 1080p cameras on my left & right side windows to make a 4-Channel system, so I did just that.

It’s been 100% reliable with no overheating issues because the A129 Plus Duo has an additional processor in the rear camera housing to share the heat load with the front main unit, (the A129 Pro Duo does not have this).

Here’s my 4-channel set up;

-Chuck

 

[CaptureYourAction]

Hello Milos,

I kind of did what you are talking about. I’ll leave a link to a video about it at the bottom.

Back in 2019 I also bought a Viofo A129 Pro Duo. I was very impressed with the front channel 4K, and underwhelmed by the rear channel 1080p. As luck would have it after 21 days the camera overheated, and self destructed. I don’t have any proof but I think the rear channel caused the main camera unit to overheat.

Fast forward to 2020 BlackboxMyCar sent me the newly released A129 Plus Duo for test & review. After testing, I liked it so much I bought a second A129 Plus Duo with my own money. I planned to just use the two front main units to build a 2K 2-channel system, and not even install the rear 1080p cameras.

I had to buy a longer 20 foot mini USB cable for the camera mounted on the rear window, and I run both cameras off the original Viofo dual USB charger. After a few days I figured why don’t I install the rear 1080p cameras on my left & right side windows to make a 4-Channel system, so I did just that.

It’s been 100% reliable with no overheating issues because the A129 Plus Duo has an additional processor in the rear camera housing to share the heat load with the front main unit, (the A129 Pro Duo does not have this).

Here’s my 4-channel set up;

-Chuck

What gauge wire is in the 20 foot USB cable?

 

[kamkar]

I know, i have just "updated" from a 1080p screen to a 1400p one,,,,,, thought the old screen died, turned out it was the GFX card,,,,, and i did not think about that, so i am out money i could have used for other stuff.
AND ! on a old spare GFX card, to which i can only comment " thank god no one make worth while games anymore" cuz the old card would suffer trying to run a modern game at 1440p.

I generally use 4K playback on youtube none the less, if they can handle it, my gigabit internet have no problems.

a rear camera are a must have if you are in 1 plate in the back of the car territory.

 

[Milos7]

Great job Chuck! 4 dash cam setup is what I was thunking about, but I stopped as I did not like my solutions for side mounting. Windows go up and down and everything else is hard to mount to or would look like "too much". Maybe I need to get more creative..
I might venture into 4 cam setup after I optimize my first two . Also I have big need of parkking time recordings, so this would reduce record time greatly.

 

[Panzer Platform]

What gauge wire is in the 20 foot USB cable?

Hello Capture,
The brand name of the cable is Ruaeoda.
The item description says 22 AWG.
It costs $9 USD.
Here is the link to it;
https://www.amazon.com/gp/B07HH8KGG2-Chuck

 

[Panzer Platform]

Great job Chuck! 4 dash cam setup is what I was thunking about, but I stopped as I did not like my solutions for side mounting. Windows go up and down and everything else is hard to mount to or would look like "too much". Maybe I need to get more creative..
I might venture into 4 cam setup after I optimize my first two . Also I have big need of parkking time recordings, so this would reduce record time greatly.

You bring up a very good point about recording time.
When I had my A129 Pro Duo, I discovered that using it as a single channel without the rear cam connected it DID NOT increase recording time.
I found Viofo permanely blocks a portion of the SD Card memory just for the rear camera.
So even though the rear cam is not being used, you do not get the available space for the front camera.
This was a huge con for me on my initial review.
My A129 Plus Duo works the same way.
-Chuck

 

[Nigel]

What gauge wire is in the 20 foot USB cable?

In general, it is better to run 12v cable to somewhere near the camera, then use the standard USB cable from either the hardwire kit, or from the standard charger if you put a 12v accessory socket on the end of your 12v cable. Then the voltage drop down the 12v cable is irrelevant, the charger/hwk will produce the same output even if you use a really long and really thin 12v cable and lose several volts!

The higher current dashcams, such as the A129 Pro do have problems with long USB cables.

 

[CaptureYourAction]

In general, it is better to run 12v cable to somewhere near the camera, then use the standard USB cable from either the hardwire kit, or from the standard charger if you put a 12v accessory socket on the end of your 12v cable. Then the voltage drop down the 12v cable is irrelevant, the charger/hwk will produce the same output even if you use a really long and really thin 12v cable and lose several volts!

The higher current dashcams, such as the A129 Pro do have problems with long USB cables.

Even the A119V3 had issues with longer USB cables, which is why I'm surprised the 20 foot USB cable worked with the A129 Pro. 22 gauge or better wire seems to be the key.

 

[Panzer Platform]

In general, it is better to run 12v cable to somewhere near the camera, then use the standard USB cable from either the hardwire kit, or from the standard charger if you put a 12v accessory socket on the end of your 12v cable. Then the voltage drop down the 12v cable is irrelevant, the charger/hwk will produce the same output even if you use a really long and really thin 12v cable and lose several volts!

The higher current dashcams, such as the A129 Pro do have problems with long USB cables.

Right on Nigel,
I agree 100%.
But, I'll have you know I'm exremely lazy. I have a 12 volt power source under a trim panel in the rear, I just can't be bothered to wire it up. lol
-Chuck