Is it worth going to 4K vs 2K resolution? Does 4K give big advantage in reading plate numbers?

[fjparks]

Hi,
I'm looking at VIFO A129 Plus Vs A129 PRO with the big difference being the respective 2K vs 4K front camera.
Opinions on if the 4K is worth the $80 and I presume a hit in memory space?
Thanks

 

[Banegio]

Check this

 

[mscott89]

Depending on your budget i'd always go for the highest resolution possible.

Especially for reading stuff like licenseplates at a distance, the higher resolution the better.

That being said, a 2K cam should be fine for picking up details like licenseplates, but the lighting can also be important and how the camera is able to adapt to the light to get proper recordings.

 

[Fabio.he]

I personally think 2K@60FPS is the best choice, then 2K@30FPS, then 4K@30FPS, the reason is, lack of devices to watch real 4K even the recording is 4K, 4K display is currently and generally applied in TV.

 

[jokiin]

2k is better suited for dashcam use than 4k, not because of playback options but it's a better balance of space/results/operating temperature, 4k has overheating issues, poorer low light performance, higher data storage requirements

 

[kamkar]

If you are happy your camera can prove everything you do with your vehicle while driving 4K is fine.
4K is not fine if :
1: You want to use parking mode.
2: You want as much small detail as possible during night / low light.

I have just gotten around to trying 2K cameras, and those seem fine, even if low light performance seem to be a step down from the best 1080p cameras.
And i am very much looking forward to trying a 4K system

My personal expectations of a dashcam is very down to earth, so much so almost anything is good enough to me.
What else i get outside of that i will of course take too.

 

[SawMaster]

The optimum cam settings and firmware approach are different day and night, so there's always some compromise going on. It was only a couple years ago that the best cam for each use were clearly two different cams, but now several cams do both very well. And as always heat is a factor. IMHO cam reliability is paramount; poor images which exist are a thousand times better than no images, so I'd place heat as the basic factor in the decision. If you're in a hot climate your best choices will be fewer

Theoretically there are great advantages to 4K, and some of that theory does happen in reality, but from what I've seen so far there is not a huge difference between a good 2K and 4K. Details such as plate number capture are hit-and-miss with all dashcams, and in the right conditions 4K does have the advantage, but not always, especially at night And there's one hidden disadvantage to some 4K cams in that using it can limit a second (and third) channel unable to do it's best as the processor has to handle the 4K data rate from the front cam as the other channels get whatever is left available. This also happens with some 2K cams, so if the rear cam also needs to do well that needs to be factored in to your decision

I think that 4K dashcams have matured and come of age now, but only just. There is room for improvement, and it will be found and utilized in time. They can be a good choice and they can do very well, but I don't see them as an absolute necessity or as always winning over a 2K cam in comparison. If you want it and the other factors I mentioned aren't a problem then by all means go 4K- it's the best we've got right now

Phil

 

[Nigel]

I personally think 2K@60FPS is the best choice, then 2K@30FPS, then 4K@30FPS, the reason is, lack of devices to watch real 4K even the recording is 4K, 4K display is currently and generally applied in TV.

An FHD (1080) monitor is perfectly good for watching 4K video, just zoom in when you want to see more detail.

Even with a 4K device, if you want to see all the detail from a normal viewing position, most people will have to either zoom in or get up and move uncomfortably close to the screen!

2k is better suited for dashcam use than 4k, not because of playback options but it's a better balance of space/results/operating temperature, 4k has overheating issues, poorer low light performance, higher data storage requirements

The data storage requirement depends on the bitrate, not the resolution, which is why some dashcam manufacturers get away with only 25Mbps for their 4K cameras, while others provide 30Mbps for 2K cameras! Use of bitrate is a tradeoff in quality between many aspects of image quality, such as frame rate, colour fidelity, resolution, pixelation, sharpness, temporal noise, etc..

In low light the 4K cameras still have the better resolution. They do tend to suffer more from noise and motion blur, but sometimes resolution is the more important of the three, the motion blur is only a problem when there is motion, and a bit of extra noise doesn't always destroy important detail even when it doesn't look nice. When stopped, a 4K dashcam should win on detail at any time there is reasonable lighting, and on a dark road at night with no headlights or streetlights, no dashcam works adequately well!

All cameras can overheat in a parked car at midday in midsummer. As long as they protect themselves, for example by shutting down, the amount of time a UHD camera is not fully functional is just a compromise to be made in return for double the detail of QHD or quadruple the detail of FHD for the rest of the year. People who live in hot places may want to make a different choice to those that live in cool places.

there is not a huge difference between a good 2K and 4K.

It is not a huge difference, just double the detail.

FHD (1080),
QHD (2K),
UHD (4K):

 

[kamkar]

On youtube i do watch stuff in 4K, even if my monitor are just 1080p.
Also would like tu upgrade to a 1440p monitor, but that is not a option at the moment.

 

[SawMaster]

It's not double the detail really- it's only that it can be double the detail. I've seen plenty of vids which I've watched carefully and while 4K is better, it's implementation keeps it from reaching that level. We've still got the same size and type of lens, so there's no more light or image reaching the sensor itself than before. And each pixel has to have it's data processed same as before. There is always some loss in those processes. And at night, each pixel is receiving only 1/4 of the light than before yet they still don't have half the minimum threshold value needed for them to respond with an image versus darkness.

So better detail yes. Twice the detail no. Only when that potential gets more fully and well used will it reach it's possibilities and we're just not there yet.

Phil

 

[kamkar]

All dashcams IMO are a bit on the low end of bitrates i like to see, from 1080 to 4K, i like 1080 to come up a smidgen more, and while i am not keeping track of the 4K systems i am almost sure i would like those to double bitrates at least.

 

[fjparks]

Thanks All for the feedback.
I'm in So Cal so heat is a concern. The only thing keeping me on the fence was that the Pro has video buffering for parking mode, but I think I will forgo that, keep $70, and go with the Plus.

 

[Nigel]

It's not double the detail really- it's only that it can be double the detail. I've seen plenty of vids which I've watched carefully and while 4K is better, it's implementation keeps it from reaching that level. We've still got the same size and type of lens, so there's no more light or image reaching the sensor itself than before. And each pixel has to have it's data processed same as before. There is always some loss in those processes. And at night, each pixel is receiving only 1/4 of the light than before yet they still don't have half the minimum threshold value needed for them to respond with an image versus darkness.

So better detail yes. Twice the detail no. Only when that potential gets more fully and well used will it reach it's possibilities and we're just not there yet.

Phil

If you are watching Youtube 4K then it certainly isn't double, but raw video from an A129 Pro in good lighting is double. In poor lighting all cameras tend to suffer motion blur, so then you only get double when everyone is nearly stopped.

The sensor is actually wider, so does get more light given the same lens F number, even if the lens barrel has the same thread. Each pixel receiving 1/4 of the light isn't an issue unless it is so dark that the sensor can't see, which isn't an issue when driving unless you are driving with no lights, it does mean that each pixel has more noise, but you should average the noise over the 4 pixels, then you see that the total noise in the image is the same.

 

[SawMaster]

I've watched a lot of raw vids too- not just YouTube with it's horrid compression. My old laptop just does 1080P but I can see the differences and I still say that it's not really twice as good at detail save for certain situations. And even then the 'lesser' 2K cams also do very well too. It's better but it's not the cure-all we need, and I don't think we will ever have that- at least not at prices we can afford.

Phil

 

[mscott89]

I've watched a lot of raw vids too- not just YouTube with it's horrid compression. My old laptop just does 1080P but I can see the differences and I still say that it's not really twice as good at detail save for certain situations. And even then the 'lesser' 2K cams also do very well too. It's better but it's not the cure-all we need, and I don't think we will ever have that- at least not at prices we can afford.

Phil

Agreed!

- Marty.

 

[Nigel]

Agreed!

- Marty.

I'm going to disagree

2K = 2x the detail of 1080,
4K = 4x the detail of 1080.
Poor lighting can reduce the detail on any of them.

As for being able to see more detail from 4K than 1080 when viewing on a 1080 monitor, that is true, a 1080 monitor can show a lot more detail than is recorded on a 1080 camera, in fact if you just count the red pixels, a 1080 monitor has 1920x1080=2,073,600 red pixels. A 4K camera also has 1920x1080=2,073,600 red pixels. A 1080 camera only has 960x540=518400 red pixels, 1/4 the number of 4K and 1/4 the number of a 1080 monitor. So if you want a camera to produce a perfect image on a 1080 monitor then you need a 4K camera, and if you want a perfect image on a 4K monitor then you need an 8K camera, that is largely why the professional broadcasters and filmmakers like to use 8K cameras even though they only ever broadcast 4K.

 

[nutsey]

4K adds 2-4 meters to the maximum distance of license plates readability comparing to 2K.

2k vs 4k (dashcams with same lenses, zoom 200%).

 

[joe384]

I've been watching some videos on youtube comparing viofo 4k v 1440p vs 1080p. (Wideorejestratory24.pl)

The 4k seems to have advantages with distance, although in certain cases the 1440p cameras end up with a better result due to other factors

I think I am looking to go 1440p for my next camera/s, the price point, space requirements etc are just about right at the moment.

 

[Paul Iddon]

I run 4k and 2k side by side. Best of both worlds...

 

[Nigel]

The 4k seems to have advantages with distance, although in certain cases the 1440p cameras end up with a better result due to other factors

With the current sensors, the 2K definitely has advantages on motion blur, while the 4K has advantages on resolution. The motion blur advantage is more likely to be critical for reading plates, so 2K is a good choice.

I run 4k and 2k side by side. Best of both worlds...

Indeed, gives the advantages of both along with redundancy for if one fails to do the job.

Also, the A129 Pro has better image quality for movie making than any of the 2K cameras.