A139 (Pro) Telephoto Remote Camera

[Dashmellow]

I used 2 pliers. One to hold the lens and another to twist the mount.

As @Dashmellow said, use a hair dryer or heat gun to warm it up around the threads and it will make it easier.

I don't generally recommend using a pair of pliers to remove dash cam lenses but over the years it has sometimes been necessary. Out of concern for damaging the lens and also to gain a better grip I use the rubber insert from an action camera bicycle handlebar mount inside the jaws of the pliers. Works much better than just a plain pair of pliers!

 

[black9white]

Finally got it installed! Thanks everyone! Definitely a user-friendly mod, the waiting time was the only annoying part.

 

[Search&Rescue]

Hi all!
WM1 will arrive soon, which I will install instead of the rear camera from the 139pro kit. I was forced to make a purchase because... I am not at all satisfied with the quality of the rear camera of the 139pro.
The rear camera will be uninstalled.
Now a question.
Tell a person whose hands are growing out of his ass - which telephoto lens to buy so that it can be installed in the rear camera without unnecessary movements? The most adapted model for carving and other tricky words (BFL / MBF) from which I get a headache.
The price is around $20, the purchase address is AliExpress.
Thank you in advance.

 

[Voldur]

The rear and internal camera connectors can be a bit temperamental. Unplug and re-plug. If you have voice notifications turned on, it should say something like "Recording, 2 channels"

I ended up connecting the internal camera to the rear camera connector and now it works.

I didn't have any plans for a rear camera so this will do.

 

[viofo]

How do you think this telephoto performance?
https://ibb.co/yy2Nzp3

https://ibb.co/nc0JTgN

 

[Dashmellow]

How do you think this telephoto performance?

Some time ago, you asked about what telephoto focal length would be best. As you know, I was the first person on DCT to demonstrate a telephoto dash cam six years ago. Over time, my views about how long a telephoto lens should be used have evolved. I've learned that it depends on how you want to use the camera and what your personal needs are. These days I prefer a wider, less powerful lens because I often travel on smaller two lane roads and I find it useful to capture cars and license plates of vehicles coming towards me in the other lane. If I have too much magnification, I miss that.

Originally, I preferred a stronger magnification like this:





These days I use a less powerful 8mm lens that allows me to capture the oncoming lane as well. I sometimes even turn the lens slightly to the left to enhance oncoming lane capture.





Here is the corresponding frame from the Viofo A119 V3 for context.


If you are finally going to produce a commercial telephoto dash cam option, perhaps a module for the A139, I would recommend doing two focal length options, one with a longer lens and one slightly wider so the buyer can decide which version works best for his particular driving conditions.

Some people may want both which could lead to additional sales.

 

[Agie]

Some time ago, you asked about what telephoto focal length would be best. As you know, I was the first person on DCT to demonstrate a telephoto dash cam six years ago. Over time, my views about how long a telephoto lens should be used have evolved. I've learned that it depends on how you want to use the camera and what your personal needs are. These days I prefer a wider, less powerful lens because I often travel on smaller two lane roads and I find it useful to capture cars and license plates of vehicles coming towards me in the other lane. If I have too much magnification, I miss that.

Originally, I preferred a stronger magnification like this:

View attachment 67415

View attachment 67419

These days I use a less powerful 8mm lens that allows me to capture the oncoming lane as well. I sometimes even turn the lens slightly to the left to enhance oncoming lane capture.

View attachment 67416

View attachment 67418

Here is the corresponding frame from the Viofo A119 V3 for context.
View attachment 67417

If you are finally going to produce a commercial telephoto dash cam option, perhaps a module for the A139, I would recommend doing two focal length options, one with a longer lens and one slightly wider so the buyer can decide which version works best for his particular driving conditions.

Some people may want both which could lead to additional sales.

That's exactly it, mobile phones for the last five or so years have been moving towards variable focal lengths (either on one lens or multiple lenses like they do now), and I think maybe even consumer security cameras so why not dash cameras.

Better to have the choice than to not have a choice at all.

 

[Dashmellow]

That's exactly it, mobile phones for the last five or so years have been moving towards variable focal lengths (either on one lens or multiple lenses like they do now), and I think maybe even consumer security cameras so why not dash cameras.

Better to have the choice than to not have a choice at all.

I began exploring telephoto lenses on dash cams six years ago using varifocal lenses and that's a great option for an enthusiast or someone skilled in photography but on a commercial dash camera product such lenses would create all kinds of user headaches and complaints because of the need to carefully refocus the lens each time you change the zoom setting. Even if you know what you are doing this can be challenging.

Different primary lenses would be the way to go and it should be kept to only two focal length options to keep things simple. Since the A139 already is available with various lens options for front, rear and interior, it would seem like the logical thing to do would be to offer a couple of telephoto modules that can simply plug into the camera, much like the modded versions @TonyM introduced.


BTW, I suggested the concept of a dual tele/wide lens dash cam five years ago in one of my threads on varifocal lenses.

June 6, 2018

Now that we have viable high quality dual channel dash cams, the chipset technology already exists to build a dual focal length front facing dash cam. All that needs to happen is to get rid of the cable and relocate the remote cam module to the front camera housing and engineer the best telephoto into it. Or it could be a base cam with a short cabled front facing telephoto with flexible positioning and aiming.

I predict such a product may yet come about.

I then predicted that @TonyM would be the first person to demonstrate a DIY version of this and he eventually did exactly that here in this thread!

June 5, 2018

@TonyM picked up on this concept the last time we talked about this idea. He may well be the first to demonstrate this as a DIY project.

Maybe my prediction that a commercial version will eventually get produced will finally come to fruition?

 

[Nigel]

That's exactly it, mobile phones for the last five or so years have been moving towards variable focal lengths (either on one lens or multiple lenses like they do now), and I think maybe even consumer security cameras so why not dash cameras.

Variable zoom might be OK during sunshine, but making a variable focal length camera with a really wide aperture for night time driving is really difficult.
Professional photographers like to use prime lenses (fixed focal length), otherwise they end up with something like:

 

[Dashmellow]

Modern zoom lenses usually have variable apertures and so maximum aperture will change as you zoom. Nigel is kind of exaggerating about how these things work for photographers in the real world.

Photographers don't use giant zoom lenses like that because they need low light performance, they use them for sporting events and photojournalism, like shooting rocket launches and other situations where they can't get close.

CCTV lenses which are what would be available for dash cameras today are similar to the M12 lenses that are in today's dash cams have fixed apertures. In a varifocal lens like this the aperture is called a "relative aperture". This means that the while the fixed aperture remains the same, the more you zoom, the smaller it appears to the sensor and the less light is reaching the sensor. From my experience this is not as much of an impediment as it may seem, although it is indeed worthy of consideration.

Under most circumstances you do not use a varifocal lens mounted on a dash cam at its full magnification or anywhere near that, so the relative aperture is not all that small as the varifocal lenses I used in my projects have wide apertures of ƒ/1.4 and ƒ/1.6. Also, similar to these massive zoom lenses, M12 CCTV varifocal lenses are much bigger than normal lenses and have much bigger lens elements than their primary lens counterparts of similar magnification. Like the big zoom in Nigel's photo CCTV lenses have larger barrels and front lens elements which let more light in when compared to their primary lens counterparts of similar focal length.

Unfortunately, dash cam manufacturers do not have the resources to design and build their own super-high tech miniature lenses like we see in mobile phones, nor do dash cams have the computing power to support them. If they did, dash cams would cost as much as iPhones. For now varifocal lenses for dash cams would be too big and heavy for a commercial dash cam and they would be impractical for the other reasons I mentioned. Their potentially smaller aperture would be the least of your problems.

A commercial multi-channel wide/telephoto dash cam needs to be plug and play.

 

[Nigel]

Modern zoom lenses usually have variable apertures and so maximum aperture will change as you zoom. Nigel is kind of exaggerating about how these things work for photographers in the real world.

Photographers don't use giant zoom lenses like that because they need low light performance, they use them for sporting events and photojournalism, like shooting rocket launches and other situations where they can't get close.

When using a telephoto lens, you need a wide aperture to avoid motion blur since motion blur increases with focal length; a wide aperture on a telephoto is expensive, a wide aperture on a zoom is very expensive.

That Sigma 200-500mm f/2.8 APO EX DG Ultra-Telephoto Zoom Lens in my image does not have enough zoom for rocket launches, and is going to be rather heavy for most sporting events. Being fixed aperture at f2.8, I'd say it is intended for use in low light, the manufacturer says: "The first ultra telephoto zoom lens to provide an aperture of F2.8 at the 500mm focal length. This lens can be used to create amazing image expression with various types of photography such astrophotography, portraits, wildlife and sports.".

The price of $26000 is another reason not to use variable zoom lenses in a dashcam, if you want quality images then they are much more expensive than a fixed length telephoto of similar image quality!

 

[Dashmellow]

When using a telephoto lens, you need a wide aperture to avoid motion blur since motion blur increases with focal length; a wide aperture on a telephoto is expensive, a wide aperture on a zoom is very expensive.

That Sigma 200-500mm f/2.8 APO EX DG Ultra-Telephoto Zoom Lens in my image does not have enough zoom for rocket launches, and is going to be rather heavy for most sporting events. Being fixed aperture at f2.8, I'd say it is intended for use in low light, the manufacturer says: "The first ultra telephoto zoom lens to provide an aperture of F2.8 at the 500mm focal length. This lens can be used to create amazing image expression with various types of photography such astrophotography, portraits, wildlife and sports.".

The price of $26000 is another reason not to use variable zoom lenses in a dashcam, if you want quality images then they are much more expensive than a fixed length telephoto of similar image quality!

The Sigma 200-500mm f/2.8 APO EX DG Ultra-Telephoto Zoom Lens actually comes with an attachment that boosts the focal length to 1000mm and it is indeed primarily a lens used by professional wildlife photographers and photojournalists.

Perhaps the most commonly used long range super zoom lens used professionally is the Nikkor 1200-1700mm f/5.6-8P IF-ED which derives its superior low light performs partly from its large front lens element along with the use of ED glass and superior lens coatings. It has also a variable diaphragm. The lens was introduced in 1990 at a base price of $60,000 and a full price of $75,000 for the complete system. Today $75,000 would be $176,181.71. Canon offers a competitive lens.



What is your point even bringing up such lenses in relation to dash cams? It's a red herring.

Those of us who have been using of zoom lenses on dash cams for the last six years have demonstrated countless times that zoom lenses perform more than adequately for the task without excessive motion blur. In fact, they often offer far sharper images with less motion blur than wide angle lenses because they capture approaching vehicles at a distance at high magnification where motion is less of an issue.

For some peculiar reason you have been attacking the use of telephoto dash cam lenses for one reason or another for years despite the fact that you have no personal hands-on experience with them. Previously, you claimed that using a 4K camera negated the need for a telephoto lens because you have more resolution to work with but anyone who has experience with telephoto or zoom lenses knows this to be completely untrue. You can achieve results you could never achieve by cropping a larger image.

And another thing you fail to understand is that the whole concept of using telephoto lenses on a dash camera is that they work in concert with the standard wide angle lens to tell the story. When one lens doesn't capture what is happening the other usually does. In actual practice, the telephoto lens captures the important details of the approaching vehicle and the wide angle lens captures the rest of the action.

 

[Dashmellow]

The price of $26000 is another reason not to use variable zoom lenses in a dashcam, if you want quality images then they are much more expensive than a fixed length telephoto of similar image quality!

I guess this whole zoom lens debate is another one of those gratuitous arguments you like to engage in. It's like you just make this stuff up, Nigel.

What you are claiming is demonstrably untrue.

The 5 MP varifocal zoom lens that made this image cost $13.90 USD.





And the 3 MP varifocal zoom lens that made this image cost $7.49 USD

 

[Agie]

The Sigma 200-500mm f/2.8 APO EX DG Ultra-Telephoto Zoom Lens actually comes with an attachment that boosts the focal length to 1000mm and it is indeed primarily a lens used by professional wildlife photographers and photojournalists.

Perhaps the most commonly used long range super zoom lens used professionally is the Nikkor 1200-1700mm f/5.6-8P IF-ED which derives its superior low light performs partly from its large front lens element along with the use of ED glass and superior lens coatings. It has also a variable diaphragm. The lens was introduced in 1990 at a base price of $60,000 and a full price of $75,000 for the complete system. Today $75,000 would be $176,181.71. Canon offers a competitive lens.

View attachment 67441

What is your point even bringing up such lenses in relation to dash cams? It's a red herring.

Those of us who have been using of zoom lenses on dash cams for the last six years have demonstrated countless times that zoom lenses perform more than adequately for the task without excessive motion blur. In fact, they often offer far sharper images with less motion blur than wide angle lenses because they capture approaching vehicles at a distance at high magnification where motion is less of an issue.

For some peculiar reason you have been attacking the use of telephoto dash cam lenses for one reason or another for years despite the fact that you have no personal hands-on experience with them. Previously, you claimed that using a 4K camera negated the need for a telephoto lens because you have more resolution to work with but anyone who has experience with telephoto or zoom lenses knows this to be completely untrue. You can achieve results you could never achieve by cropping a larger image.

And another thing you fail to understand is that the whole concept of using telephoto lenses on a dash camera is that they work in concert with the standard wide angle lens to tell the story. When one lens doesn't capture what is happening the other usually does. In actual practice, the telephoto lens captures the important details of the approaching vehicle and the wide angle lens captures the rest of the action.

Thank you for your detailed explanation, does make sense and I too was a bit perplexed when the giant lenses for sports/wildlife was brought up. I understand somewhat the prime lenses since I have a few f1.8 prime lenses for my Olympus mirrorless M4/3 camera, needing the light let in for some good images.

As you showed, it's reasonably cheap for dashcam manufacturers to get on this concept and get some results. I would have said that (much like the not-so-big phone manufacturers out there) that the profit margins in dash cam wouldn't be very big at all. Which would explain why there's money in the kitty for development on off-the-shelf image sensors, but not for research.

Still, why not have the best of both worlds with a telephoto and normal lens. Sony should make these a reality for their Starvis line, because no one else is going to fork out and do it for the industry - it's been six years already since you showed it can be done!

 

[Dashmellow]

Sony should make these a reality for their Starvis line, because no one else is going to fork out and do it for the industry - it's been six years already since you showed it can be done!

I don't see Sony getting too deep into anything specifically to do with dash cams other than produce their outstanding Starvis sensors which get used in many types of cameras. All in all, the dash cam market, at least as it stands now, isn't big enough to interest them as an investment. They did get involved with the action camera market so there's hope, but the action camera market is huge worldwide compared to how many dash cams are sold. By comparison the dash cam market is tiny. That's slowly changing though. When I bought my first dash cam twelve years ago (a Chinese generic) nobody I talked to knew what a dash cam was and it was several years until I even saw another dash cam in somebody's car. Even now I don't see that many other cars with dash cams when I drive around but I see way more than I used to. The dash cam market is still pretty young.

I remember when I was the only one with a dash cam I felt like I had some kind of secret weapon. Even friends and random people who noticed it on my windshield didn't know what it did.

 

[Agie]

I don't see Sony getting too deep into anything specifically to do with dash cams other than produce their outstanding Starvis sensors which get used in many types of cameras. All in all, the dash cam market, at least as it stands now, isn't big enough to interest them as an investment. They did get involved with the action camera market so there's hope, but the action camera market is huge worldwide compared to how many dash cams are sold. By comparison the dash cam market is tiny. That's slowly changing though. When I bought my first dash cam twelve years ago (a Chinese generic) nobody I talked to knew what a dash cam was and it was several years until I even saw another dash cam in somebody's car. Even now I don't see that many other cars with dash cams when I drive around but I see way more than I used to. The dash cam market is still pretty young.

I remember when I was the only one with a dash cam I felt like I had some kind of secret weapon. Even friends and random people who noticed it on my windshield didn't know what it did.

We can only hope then that the market gets bigger. I wonder though with all the newer cars having dashcams built in, if that will eventually trickle down the line into cheaper (new) cars too and just put all these dashcam manufacturers out of business. A slow death by a thousand cuts...

 

[Dashmellow]

I wonder though with all the newer cars having dashcams built in, if that will eventually trickle down the line into cheaper (new) cars too and just put all these dashcam manufacturers out of business. A slow death by a thousand cuts...

That's a good question and I don't know the answer. I suspect that the dash cam market will survive due to the fact that car manufacturers tend to ask outrageous prices for add-on options like dash cams and they often under-perform as well. Many people will probably come to realize they can install their own better performing ones at a fraction of the price of what they would get from the car dealership when they buy the car.

 

[TonyM]

How do you think this telephoto performance?
https://ibb.co/yy2Nzp3

https://ibb.co/nc0JTgN

Just looking at those single frames, the performance looks good to me.

The telephoto is darker than the wide angle, but IMO that helps to minimise motion blur and preserve highlight detail. Personally I don't mind the telephoto being a bit darker than the wide angle, since both are working together to record the scene, but other users may have a different opinion?

Are you testing the telephoto lens on a STARVIS 2 camera with HDR, perhaps the 5MP IMX675?

I agree with the comments above by @Dashmellow about offering a short telephoto around 8mm focal length, to ensure the oncoming lane is covered even on curved roads.

 

[DoubleDawg]

Are you testing the telephoto lens on a STARVIS 2 camera with HDR, perhaps the 5MP IMX675?

I believe they are testing on the A139 (pro) rear IMX291 camera, based on hints posted by them such as (this one is on the a229 pro forum):

For A139 Pro, soon there will be a new option.

 

[Agie]

That's a good question and I don't know the answer. I suspect that the dash cam market will survive due to the fact that car manufacturers tend to ask outrageous prices for add-on options like dash cams and they often under-perform as well. Many people will probably come to realize they can install their own better performing ones at a fraction of the price of what they would get from the car dealership when they buy the car.

Very true, so we should be safe for years to come hehe