Mobius 5MP Varifocal Zoom 6-22mm ƒ/1.6

Here are some interesting zoom telephoto-vs-normal dash cam captures using the Mobius with this 6-22mm Varifocal ƒ/1.6 zoom compared to the FOV of the SG9665GC (112º).

In the following images, I set the zoom of the 6-22mm Varifocal to approximately 1/3 or maybe 3/4 of the potential zoom. The lens has no calibration markings so I can only guesstimate the actual focal length setting here but you get the idea. This is all experimental at this point, of course.

So, here are some recent screen captures of very nearly the same frame from the two different cameras. I've superimposed in green frames the actual FOV of the zoom telephoto varifocal as compared to the SG9665GC.

I would never wish to be without a traditional wide angle dash cam, but now that I've been playing around with CCTV varifocal lenses in a Mobius deployed as a second front facing camera for almost ten months, I think I wouldn't want to be without this capability.

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. ;)

Mobius (1) 6-22mm Varifocal Zoom ƒ/1.6
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Street Guardian - SG9665GC V2
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Mobius with 6-22mm ƒ/1.6 Varifocal Zoom - Lower Main Street
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Street Guardian - SG9665GC V2
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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. ;)

wouldn't be too hard to DIY something with our dual channel, we already have short cables for using the second camera up front, would only be matter of finding a suitable lens for the second cam, wouldn't look real pretty with the current rear cam design but as a DIY it might be something people are willing to tackle, we just added an invert option for the second cam also as there are times where the install calls for something different, gives us a bit more flexibility
 
wouldn't be too hard to DIY something with our dual channel, we already have short cables for using the second camera up front, would only be matter of finding a suitable lens for the second cam, wouldn't look real pretty with the current rear cam design but as a DIY it might be something people are willing to tackle, we just added an invert option for the second cam also as there are times where the install calls for something different, gives us a bit more flexibility

@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. I've thought for awhile now about converting my mini-0906 pre-production sample for this purpose but I just don't have the time this time of year. Hope to get to it eventually and see if I can make it work but I usually engage in projects like this during the deepest parts of winter.
 
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Would be a while before we'd have a chance to do that, too many other projects on the go already is keeping us busy
 
Here are some interesting zoom telephoto-vs-normal dash cam captures using the Mobius with this 6-22mm Varifocal ƒ/1.6 zoom compared to the FOV of the SG9665GC (112º).

Very impressive results. (y)

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.

Such a camera with high quality glass would be brilliant. :)

However, care would need to be taken that the bit rate wasn't compromised as I understand many existing 2 camera systems run a much lower bit rate on the rear camera to accommodate the extra processing / file storage, which results in a lower quality picture from the rear. It would be a real shame if the 2nd zoomed camera was compromised on quality because of this. TBH, given the size of the Mobius cameras, I personally wouldn't be adverse to seeing 2 complete camera solutions in a single double size height housing eg 2 main boards / chipsets, 2 SD slots etc. It would be smaller than many other manufacturers single housings. It also gives some redundancy albeit it doubles the price and increases heat dissipation issues.
 
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. ;)

Such a camera with high quality glass would be brilliant. :)

However, care would need to be taken that the bit rate wasn't compromised as I understand many existing 2 camera systems run a much lower bit rate on the rear camera to accommodate the extra processing / file storage, which results in a lower quality picture from the rear. It would be a real shame if the 2nd zoomed camera was compromised on quality because of this.
Dual-camera systems such as the SG9663DC and A129 Duo can use the same bitrate for both front and rear cameras, at a value which is comparable to other single-channel cameras. For example the A129 Duo can run at 16+16Mbps. A single Mobius runs at 17Mbps.

TBH, given the size of the Mobius cameras, I personally wouldn't be adverse to seeing 2 complete camera solutions in a single double size height housing eg 2 main boards / chipsets, 2 SD slots etc. It would be smaller than many other manufacturers single housings. It also gives some redundancy albeit it doubles the price and increases heat dissipation issues.
Do you mean something like this, but with wide-angle and telephoto lenses?
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Do you mean something like this, but with wide-angle and telephoto lenses?
View attachment 38684

That's nice...just 3dprint a common upper shell which replace both top ones and you have 1 solid dual optical camera.
 
@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. I've thought for awhile now about converting my mini-0906 pre-production sample for this purpose but I just don't have the time this time of year. Hope to get to it eventually as see if I can make it work but I usually engage in projects like this during the deepest parts of winter.
Yes, I have been thinking of a DIY project using the A129 as a dual-camera platform, by swapping out one of the lenses for a telephoto. It's OT for this thread, but I'll probably use a compact 6mm or 12mm lens rather than a larger varifocal.
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I could do with a shorter connecting cable though. I tried it briefly with the rear camera alongside the main unit as @jokiin described, with the 20' cable routed half-way around the car and back again!
 
I've become aware that several people watching this thread who have expressed an interest in purchasing this 6-22mm varifocal ƒ/1.6 zoom lens with a pre-installed IR-cut filter have experienced some uncertainty about whether or not Treeye has adopted my recommended method for installing the IR filter in varifocal lenses. They have! The confusion seems to revolve around the fact that their older photos of their varifocal lenses are still on AliExpress. There is also some confusion about whether this method of filter installation is a special request or whether all varifocal lenses with IR-cut filters would now be shipped this way. So, I had some recent discussion with Treeye about all this and as a result they've updated their product photo to clarify what to expect if you place an order.

6-22mm_varifocal.jpg
 
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I've become aware that several people watching this thread who have expressed an interest in purchasing this 6-22mm varifocal ƒ/1.6 zoom lens with a pre-installed IR-cut filter have experienced some uncertainty about whether or not Treeye has adopted my recommended method for installing the IR filter in varifocal lenses. They have! The confusion seemed to revolve around the fact that their older photos of their varifocal lenses were still on AliExpress. There was also some confusion about whether this method of filter installation was a special request or whether the all varifocal lenses with IR-cut filters would now be shipped this way. So, I had some recent discussion with Treeye about all this and as of today they've updated their product photo to clarify what to expect if you place an order.
It's great to see a seller take on board suggestions for improvement, and good that you took the time to identify the root cause of the problem and propose your solution to them.
 
It's great to see a seller take on board suggestions for improvement, and good that you took the time to identify the root cause of the problem and propose your solution to them.

Well, Treeye was happy to have a method that avoids any filter dislodging problems going forward. At first there was a little confusion on their part about exactly what I was suggesting and how to achieve it but after I explained in more detail how to go about it they tried it and saw the benefits. The folks at Treeye have been exceptionally friendly and helpful to deal with and they were very receptive to considering my suggestions. They were the same way about resolving the problem when I reported that the IR filter had come loose. It was just a matter of coming up with the best way to deal with the issue.

Interestingly, there's an optical benefit to installing the filter directly over the rear lens element rather than 6-7mm away on the very end of the lens tube. (distance depending upon how it is focused). Light entering the front of the lens will eventually bounce off of the IR filter mounted on the rear of the lens tube and scatter around the dead space between the filter and the rear lens element. Light that bounces around inside a lens tends to reduce overall image contrast, so having the IR filter mounted directly on the rear lens element only a millimeter away will dramatically reduce any internal reflections. Of course, I don't know whether this makes for any practical difference in the results we can achieve but that's how optical lens systems work so why not go with the more optimal approach, especially if it avoids other issues.

The trick to installing a 9.5mm filter on one of these lenses is to adjust the focus of the varifocal so that the rear element comes all the way to the top so you have good access to the back of the lens and the rear element. This allows you to work on the lens more easily and make sure the filter is properly aligned before securing it in place with UV light. It's a good idea to work the focus in and out with the unglued filter in place so you can observe how it works. It's vitally important not to allow any cement to get on the inside of the tube or onto the rear lens element.

Bringing the rear element up as far as it can go will also demonstrate why focusing the lens to its ultimate extreme like this would likely tend to push a filter mounted directly on the rear of the lens tube right off its mount.

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Dual-camera systems such as the SG9663DC and A129 Duo can use the same bitrate for both front and rear cameras, at a value which is comparable to other single-channel cameras. For example the A129 Duo can run at 16+16Mbps. A single Mobius runs at 17Mbps.


Do you mean something like this, but with wide-angle and telephoto lenses?
View attachment 38684

I'm aware there are some cameras that run the same bit rate back and front, but many don't, and I'm just a little afraid that having a single board processing two inputs may keep the quality and bit rate low. As long as that can be avoided, I'm all for any solution that works or is elegant. Personally, I'm still not a fan of low bit rates, but understand that manufacturers are doing this to ensure competitive looking recording times when compared to other manufacturers products. For me, the way forward here is to offer a "Pro" mode, where the camera by default runs maybe 10-15mbs for long recording times, but the advanced user can choose to run a much higher rate at the sacrifice of recording time eg. maybe something between 30-50mbs. I'm just not a fan of banded skies and blurred grass and trees. Yep I know it's superficial to what a dashcam is intended for, but footage can be potentially used for many purposes other than just accident proof, and it's nice to have a perfect picture.

As for the above design, yes essentially a single case version of the above is one possible solution, but I don't want to take away from anything more elegant using shared components that Dashmallow may have already got planned with whichever manufacturer he's liaising with.


That's nice...just 3dprint a common upper shell which replace both top ones and you have 1 solid dual optical camera.

See above.
 
Just out of interest, whats the intention for a dual lens production version, to go with this zoom, or a prime equivalent?

Well, many of us who have been experimenting with aftermarket telephoto lenses in our dash cams (primarily the Mobius) have found great benefit in having such optical reach and highly detailed capture of cars and scenes out in front of us. Of course, not one of us would be willing to give up our more traditional wide angle dash cams in lieu of just having the telephoto. Since the chipset technology for high quality dual channel cameras already exists and is already on the market in another form factor, certainly an integrated dual wide/telephoto lens front facing camera is quite viable and may have much appeal to a certain segment of the dash cam buying public.

It would not surprise me to learn that some enterprising dash cam developer has been reading this thread and is already putting the wheels in motion. ;)
 
Having finally found what I think is a decent focus point on this lens, I have spent a little while looking at where it adds significant benefit over my wide-angle cameras - in this case the F1.5 Mobius Maxi. The two cameras are mounted side-by-side so they have almost identical views of the road ahead. The Maxi is recording 2.7k 30fps. The M1 is recording 1080p 30fps.

Looking into the late afternoon sun, the Maxi picks up a lot of dashboard reflections and glare from the sun hitting the front of the lens. Plus there is so much bright sky in the scene that the cars are underexposed.
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By comparison, the Mobius 1 with the 6-22mm varifocal set to about half-way through the zoom range delivers a clearer view that has noticeably less glare and dashboard reflections. With the sky absent from the scene, the exposure of the cars is much better.
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I get a similar result later when driving towards the sun. The wide view of the Maxi gives good context to everything that is happening ahead of me.
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The M1 with varifocal presents a narrower FOV giving more detail of the road ahead, once again with better exposure on the road and cars with very little sky in the frame.
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Looking now at side-lighting, with approach speeds of 60+60=120mph, the Maxi with its fast F1.5 lens renders a sharp image even with the oncoming car close to the edge of the frame. Exposure is now much better since glare and reflections are reduced.
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The M1 with the varifocal has a fairly good image considering I'm bouncing along the road at 60mph. Here the Mobius 1 shows that it has a narrower dynamic range than the Maxi
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Finally a look at a car waiting to turn at the junction ahead of me. The Maxi with its wide angle FOV shows the approaching car in the opposite lane, plus the road markings which show where the cars are supposed to be.
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The narrow FOV of the varifocal lens on the M1 shows just half of the car ahead, but in much greater detail. Viewed in isolation, the lane markings do not make much sense.
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As has been mentioned earlier, the narrow FOV from such a lens as this 6-22mm varifocal is too extreme to be used on its own. However as a partner to a wide-angle dashcam it offers complimentary video evidence with enhanced detail across a small area of the scene, and at times it excels where the traditional wide-angle lens struggles in challenging lighting conditions.
 
Well, many of us who have been experimenting with aftermarket telephoto lenses in our dash cams (primarily the Mobius) have found great benefit in having such optical reach and highly detailed capture of cars and scenes out in front of us. Of course, not one of us would be willing to give up our more traditional wide angle dash cams in lieu of just having the telephoto. Since the chipset technology for high quality dual channel cameras already exists and is already on the market in another form factor, certainly an integrated dual wide/telephoto lens front facing camera is quite viable and may have much appeal to a certain segment of the dash cam buying public.

It would not surprise me to learn that some enterprising dash cam developer has been reading this thread and is already putting the wheels in motion. ;)

I whole heartedly agree, just wasn't sure whether the intentions were to have Wide + Zoom, or Wide + Telephoto Prime (equivalent to the focal length you've been experimenting with).
 
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