Mobius Varifocal Zoom IR

Dashmellow

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For quite some time I'd been noticing an interesting M12 zoom lens on Banggood selling at a very attractive price and finally went ahead and ordered one. This is a fast ƒ1.4 - 2.8mm to 12mm Varifocal manual zoom designed for CCTV cameras that will accommodate a 1/3 inch sensor and captures an angle of view ranging from 25º to 110º. This lens is specifically designed for IR work and therefore does not have an integrated IR-cut filter. The lens has proven itself to be of remarkably high quality for the money, both in its physical construction and especially optically.

My original plan was to immediately install an IR-cut filter and use the lens to capture normal true color video but after installing the lens on a Mobius (1) camera I decided to play around with some Infra-Red videography. The results ended up kind of blowing my mind and have totally altered my dash cam experience going forward. What started out as some fun, temporary hobby experimentation is quickly becoming an essential camera in my vehicle and elsewhere.

The main thing to keep in mind is that the results I present here could ONLY have been achieved with the Mobius action camera and no other. I will explain further and elaborate on this later in this thread but essentially I have been able to use the unique color balance and exposure adjustment capabilities of the Mobius to achieve the imagery you will see here. Once again, the Mobius has proved itself to be the most versatile, practical, interesting and fun video camera I've ever owned and it is the reason I love the Mobius platform so much.

banggod1.jpg

When I first got this lens I was worried that it would be fragile when mounted on a Mobius and require handling with kid gloves. Instead it has proved to be extraordinarily solid and the whole package has a certain heft and integrity as if it was designed like this to begin with. One thing I did do was swap the original threaded base module with a slightly beefier one that I installed onto the original sensor plate. I did that because I used an older Mobius lens module for this project that had some slightly damaged lens threads and opted to repair it rather that use the existing "A" module in the camera that I decided not to mess with. I'll talk more about that and post a photo later on in this thread.

Due to the abysmal bandwidth I'm stuck with out here in the middle of nowhere I'm going to start by telling this story with still frames. Eventually, I will post some short videos but where I live a 5 minute clip can take as much as an hour and a half to upload over my 3 Mb/768 Kbps DSL connection. There's a lot to show and talk about here. I'll do it over the course of several posts as time permits.

tripodmount.jpg

pod_set-up.jpg

These landscapes are among my first color and exposure tweaking experiments with this lens. Captured a bee in flight! :)
IRbee1.jpg

IRview.jpg

This is the same scene as above shot a few minutes later with a normal Mobius A lens camera.
normalview.jpg

The important thing to understand here is that all digital camera sensors are inherently sensitive to the near infra-red spectrum and slightly above. For this reason all digital cameras such as dash cams are fitted with IR-cut filters to filter out IR light between about 740nm and 1000nm.

In "normal" true color digital photography Blue is from 400 - 500 nm (nanometers), green is from 500 - 600 nm and red is from 600-700 nm. IR starts at 700 nm and for photography extends to about 1,000 nm. 1,000 nm is called a micron. Longer wavelength IR used in systems to see heat levels as in thermal imaging cameras like the Flir are between 1 - 10 microns or 1,000 to 10,000 nm. For our purposes we are concerned with "near infra-red" of approximately 700 nm to 1000 nm or thereabouts.

If you do not have an IR-cut filter on a digital camera lens you will end up with a purplish or magenta image. Typical results look like this image:
ircut.jpg

Without an IR-cut filter on this particular 2.8mm to 12mm Varifocal zoom and the Mobius camera set to its default settings the images look like this:
default_color.jpg

By using the exposure and color balance settings in Mobius mSetup I was able to manually tweak the default IR results you see just above here completely without the use of any specialized filters into a more true color image that, while still IR "false color" it is now much closer to reality to the point where it becomes a viable dash camera that captures the true color of cars and other objects. At the same time it is still very much an IR image which offers unique capabilities that can reveal details not captured by traditional dash cams while often producing stunning looking "otherworldly" imagery.
roadgrab1.jpg
 
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Dashmellow

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Here is a comparison of a normal color Mobius image and an IR Mobius image so you can get an idea of how the camera is seeing color.
The photos were taken within minutes of each other under the same lighting.
normal-flowers.jpg
IR-flowers2.jpg
 
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Dashmellow

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Before I post anything further I wanted to talk about color balance and exposure a bit and explain how I've achieved the results here.

As I mentioned above, ONLY the Mobius camera can produce the sort of IR imaging you will see in this thread as it is the only camera on the market with such remarkable and extensive control over exposure and color balance.
Traditional IR photography is done with glass filters that pass specific wavelengths of light to achieve specific effects. This is similar to the way the IR-cut filter on digital cameras blocks the near infra-red part of the spectrum that causes an overall magenta cast to the image and passes the wavelengths our eyes see to produce normal color. Here, instead of using color correction filters I was able to use the controls in the mSetup application to "hack" the overall magenta/purple IR color balance into a more "natural" looking color balance without the use of filters by manipulating the RGB values and other parameters in mSetup.

Standard RGB (RED/GREEN/BLUE) is divided into three channels ranging in value from 0-255 each. All things being equal when each channel is balanced you get white, otherwise known as "white balance".

By changing those values in mSetup you can bring the false IR color closer to normal.

This has been an evolving work in progress but here are the adjustments I'm currently using to achieve the images seen below.

Edit: Here are my currently revised "advanced image settings" for the varifocal lens as of 9/4/17.

9:4.png

mSetup RGB value default is 256 (1-256 instead of the standard 0-255)
RGB.jpg

AdditiveColor.svg.png
 
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Dashmellow

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Here is the camera mounted in my vehicle. It has become an amazing companion to the SG9665GC often outperforming it by capturing remarkable and unexpected detail.
Partly, this has to do with the telephoto effect of how I'm using this lens which I have set near it's zoom maximum but the IR sensitivity of the camera captures things that no ordinary camera can see. Aside from that, this lens has shown itself to be a superb optic that is tack sharp and well corrected; an astonishing bargain considering the price.
windshield_mounted.jpg

To give you an idea of the capabilities this camera here is a direct comparison with the GC so you can see the difference between the focal lengths.
While I wouldn't want to be without a standard dash camera like the SG9665GC I am finding that having a zoom IR camera produces some amazing captures.

I have chosen these two images because the car is captured in the exact same frame in each camera. Note the arrows showing the position of the rear wheel.
Also notice how the IR sensitivity is capturing all the shadow detail in the pine trees that the standard RGB GC is not picking up at all. That's known as the "Wood effect" and I'll talk more about that later in this thread. In any event, the camera often has an uncanny ability to "see" things you don't expect because it is capturing wavelengths of light beyond the visible spectrum of what the human eye or a typical camera can usually see but that can be captured by the near infra-red sensitive sensor. What is important here is that my color corrections in mSetup are providing true enough color for dash cam work. A red car looks red, a blue car blue, etc. Finally, notice the outstanding license plate number capture compared to the Street Guardian.

SG-close-compare.jpg
Mobius-close-compare.jpg
 
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Dashmellow

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One of the interesting things about this lens is that it can give you the sometimes disconcerting visual impression that you are outside your vehicle sitting on the hood. It also makes you appear as if you are way too close to other cars in certain situations.
Here I'm parked in a space at the local shopping center and while the parking spaces there are a little short for the average sized pick-up truck I am not anywhere as near to this truck driving past me as it seems. This lens is also proving very good at eliminating motion blur in many situations. The clarity of this image is impressive considering that the truck is driving past at a good clip. The image is benefiting from the ƒ1.4 aperture on this lens and also the fact that it was captured in very bright sunshine.
parkinglot_close_up.jpg

Here traffic is moving at about 50 mph yet license plate capture is good. I have other examples that are better but I'm not sure where they are at the moment. I'll follow up on this later. In the meantime, note that you can peer into the cab of the oncoming car. I've been noticing that in some situations the camera seems to minimize windshield reflections due to the fact that the near infra-red being recorded is not reflected quite the same way as the rest of the spectrum. At times it feel like there is a CPL filter on the lens even though there is not. (I've been experimenting with a CPL on this lens but that's a whole story for another time.)
motion_blur1.jpg

Another crisp image.
pc-parking_lot.jpg

One thing I've been noticing is that I can sometimes capture details that would be lost to other cameras. In this case, my headlights are not blowing out the white car and license plate as much as one might expect. Often the wavelengths of near infra-red light that the camera captures retains details that would otherwise get lost to the normal visual spectrum. I'm still exploring this aspect and will post more about it over time.
volvo.jpg

Sometimes what would otherwise be mundane images have this amazing unreal beauty to them. This effect should really get interesting about a month from now when the trees start changing color during foliage season.
centerroad.jpg
 
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jokiin

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I've often thought it would be good to have a dual lens cam with one regular lens and one zoom like this, neither are perfect by themselves but by using the two you would get the best of both, detail (zoom lens) and context (regular lens)

would be interested in seeing the zoom lens with an IR cut filter to see how it fares
 

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Well there goes my budget again- I'm going to have to follow in your footsteps because this is just too good to not have :D Do you think the current Mobius lens base will do OK here? I think you used an older one which I don't have. And I'm wondering about nighttime pics, tried anything with that yet?

Phil
 
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Well there goes my budget again- I'm going to have to follow in your footsteps because this is just too good to not have :D Do you think the current Mobius lens base will do OK here? I think you used an older one which I don't have. And I'm wondering about nighttime pics, tried anything with that yet?

Phil

Well, I have some good news on the budget front. After I purchased this lens I discovered that Banggood also sells what "appears" to be the same lens for only $5.60. The lens I purchased is actually listed as a 2MP lens but people have been reporting that they are receiving a 3MP lens instead, as I did. The cheaper lens is listed as 3MP and does appear to be the same. The only issue is that when I checked just now it says, "Under restocking. It will be available soon", but the one I purchased is listed as in stock. Might be worth just paying the extra $1.89. Either way, notice the universally high 5 star praise these lenses receive in the review section at the bottom of the page. BTW, CCTV lenses such as this are widely available across the internet, including this exact same one, except that here it is selling for less that half or better than what you will find it for elsewhere.

The existing Mobius module lens barrel mount should be fine. I wouldn't have changed the one I have if I hadn't damaged the threads on the original by over-tightening the lock screw one too many times.

M12_zoom.jpg
 

kamkar

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I have a similar lens with a bit more Zoom, a i heavy little sucker for sure.
As i recall many birds and bees have that IR perspective look on things.

 

sydney2218

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Amazing , innovative & inspiring work. My aim is to put on a monitor ,compact one, with minimal leads & a tidy look.
 

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The 'budget-buster' is more in getting another Mobius- the lens is cheap enough. The only one I currently have is 3 years old and has seen lots of heat which might have degraded the plastic lens base, and it's my primary front cam so for now I'd rather not risk damaging it and I don't have a tested replacement for the front cam yet anyway. Better to just get a new cam as I can use another (more on that in the newest 'side-cam' thread) ;) Along with the crisp images and the zoom, it's the IR aspect which intrigues me the most. If the same settings render a good night-time image this could solve several problems which my brain has found no really good solution for to this point.

And once again the uniqueness of the Mobius shines brightly among the many newer cams which have come along since it's inception :D

Phil
 
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Dashmellow

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The 'budget-buster' is more in getting another Mobius- the lens is cheap enough. The only one I currently have is 3 years old and has seen lots of heat which might have degraded the plastic lens base, and it's my primary front cam so for now I'd rather not risk damaging it and I don't have a tested replacement for the front cam yet anyway. Better to just get a new cam as I can use another (more on that in the newest 'side-cam' thread) ;) Along with the crisp images and the zoom, it's the IR aspect which intrigues me the most. If the same settings render a good night-time image this could solve several problems which my brain has found no really good solution for to this point.

And once again the uniqueness of the Mobius shines brightly among the many newer cams which have come along since it's inception :D

Phil

I guess if you put away a little money each week you'll have what you need to put this together. It's funny timing but just yesterday I counted up all the pocket change I've been stashing away for I don't know how long and discovered that I have over a hundred bucks of "mad money" for my next purchase. Another option is to just buy the components. You can buy a Mobius PCB from eletoponline365 for just over 38 dollars and slowly add the other components. Two of my Mobius cams were built from parts I've amassed. Also, if you buy a lens from eletoponline365 they'll send you a case for free along with the module.

I forgot to answer your question last night about night shooting. I've done a little bit of experimentation so far but not much. The camera does seem to function with external IR illumination much like a surveillance camera. I'm still testing this.

As far as general night performance I need to do some actual testing in average conditions. Living in a rural area where there are no street lights everything is pitch black driving around the roads here except my headlights or oncoming cars so it doesn't tell me much. One day soon when I'm out and about in town for the evening I'll be able to get a better feel for what results I get at night. I would need to drive ten miles to get to a place with street lights and average conditions most people think of a "night driving".
 
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