Mobius Varifocal Zoom IR

Because most of us don't have this product and it costs a lot

I think you missed or misunderstood what I've been talking about here for awhile now like yesterday when I mentioned that "These low priced UV glue pens may very well just be a version of the same type of acrylamide/acrylate UV adhesive marketed for professional purposes. The pen I have contains .14 oz. (4 grams); plenty enough for cementing numerous filters".

For a few dollars you can buy 4 grams of UV cement that from all appearances is a general purpose consumer version of the types of professional UV cements we've been discussing. I bought a tube of it at a local discount store for about $2.00. It even comes with a "fauxton LED flashlight" UV light source. This stuff is widely available on Amazon at very reasonable prices. Initial tests suggest it will work perfectly for installing IR filters on lenses.

lazerbond.jpg
 
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Some of these UV cements are highly specialized for precision optical purposes, so the user may need to use specific curing methods and follow the manufacturers instructions to the letter. Gluing an IR-cut filter along the edges or using a tack weld in a few places on the back of a small lens is probably far less critical. Many of these UV cements seem to function using the same basic chemistry and physics but each one is formulated to have different properties.

Edit: Glad to hear that the company is responsive and helpful! :)

Something I did find out, the UV flashlights used for curing the glues they use have LED bulbs, well those kind of bulbs (LED) only work in a narrow band for example 285 to 400nM. This means that the bulbs have to work with the glue formula to make the cure happen. Your dispenser came with it's own little light that was assembled correctly by the company with the right wavelength for their glue formula. Meaning the UV bulb must be designed ( proper UV wavelength) for the glue formulation

If you had bought glue and a UV flashlight from different manufactures it might and might not work! For anyone contemplating doing this you have to find out from the glue manufacture what UV wave lengths are necessary to cure their glues and get the appropriate light. A little something they don't tell one in the adds for the glues or flashlights!!

Looking forward to seeing a picture of your lens gluing technique :cool:

Is the picture you posted (Laser Bond) the glue that you used?
 
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Something I did find out, the UV flashlights used for curing the glues they use have LED bulbs, well those kind of bulbs (LED) only work in a narrow band for example 285 to 400nM. This means that the bulbs have to work with the glue formula to make the cure happen. Your dispenser came with it's own little light that was assembled correctly by the company with the right wavelength for their glue formula. Meaning the UV bulb must be designed ( proper UV wavelength) for the glue formulation

If you had bought glue and a UV flashlight from different manufactures it might and might not work! For anyone contemplating doing this you have to find out from the glue manufacture what UV wave lengths are necessary to cure their glues and get the appropriate light. A little something they don't tell one in the adds for the glues or flashlights!!

Looking forward to seeing a picture of your lens gluing technique :cool:

Is the picture you posted (Laser Bond) the glue that you used?

Since a lot of these UV cements are often used by technicians and scientists working with precision optics in laboratory settings it makes sense that highly specific wavelengths and other curing specifications (like heat) would be so refined. I know UV LEDs can be made for fairly specific wavelength requirements as can other light sources. Then again, 285 to 400 nm covers most of the medium (UV-B) and long wave (UV-A) part of the UV spectrum so maybe there is a fair amount of leeway in which LED UV light sources can actually work? I know one thing is that the intensity of UV light is a factor so I guess it depends on the amount of surface area of the cement and the depth the UV needs to penetrate. Accordingly, I imagine these little LED flashlights that come with the UV glue pens will only work on very small projects but I think cementing filters onto lenses seems like a perfect application for this product. I'm no expert in this subject but as long as I can mount the IR-cut filters securely and cleanly to the back of my lenses I'm happy. I don't feel the need to overthink this.

Yes, Lazer Bond is the product I have. I came across it at a discount store and thought it would be an interesting product to experiment with so I bought some. At that time I wasn't even thinking about using it for IR-cut filter mounting.
 
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Since a lot of these UV cements are often used by technicians and scientists working with precision optics in laboratory settings it makes sense that highly specific wavelengths and other curing specifications (like heat) would be so refined. I know UV LEDs can be made for fairly specific wavelength requirements as can other light sources. Then again, 285 to 400 nm covers most of the medium (UV-B) and long wave (UV-A) part of the UV spectrum so maybe there is a fair amount of leeway in which LED UV light sources can actually work? I know one thing is that the intensity of UV light is a factor so I guess it depends on the amount of surface area of the cement and the depth the UV needs to penetrate. Accordingly, I imagine these little LED flashlights that come with the UV glue pens will only work on very small projects but I think cementing filters onto lenses seems like a perfect application for this product. I'm no expert in this subject but as long as I can mount the IR-cut filters securely and cleanly to the back of my lenses I'm happy. I don't feel the need to overthink this.

Yes, Lazer Bond is the product I have. I came across it at a discount store and thought it would be an interesting product to experiment with so I bought some. At that time I wasn't even thinking about using it for IR-cut filter mounting.
Whoops I made a mistake in the amounts I gave for nM, it should read 385 to 400nM. You would only have to overthink things if you bought the glue/light from different sources. I have a little graphic I can show if I can find it. I'm going to get the same light pen you bought, it worked for you, that's good enough for me!


Here is a small graphic showing LED frequencies in NM, interesting stuff!
https://www.assemblymag.com/articles/91449-boost-productivity-with-uv-curing-adhesives
 
Whoops I made a mistake in the amounts I gave for nM, it should read 385 to 400nM. You would only have to overthink things if you bought the glue/light from different sources. I have a little graphic I can show if I can find it. I'm going to get the same light pen you bought, it worked for you, that's good enough for me!


Here is a small graphic showing LED frequencies in NM, interesting stuff!
https://www.assemblymag.com/articles/91449-boost-productivity-with-uv-curing-adhesives

Well, I haven't actually installed the IR-cut filter on a lens and used it in everyday normal service yet, so perhaps hold off saying, "it worked for you". :nailbiting: While I'm not expecting any problems and as far as I can tell, Lazer Bond should be a good solution, you never know. :geek: If you try it too, I'll be very interested in learning of your experience.

Interesting link!
 
Also, remember to minimize the amount of adhesive in areas that the light cannot penetrate as it may not cure. The IR filter I installed also seem to cut UV light that is why I applied the glue blobs on the filter and to the side only.
 
Also, remember to minimize the amount of adhesive in areas that the light cannot penetrate as it may not cure. The IR filter I installed also seem to cut UV light that is why I applied the glue blobs on the filter and to the side only.

I think the particular cut filter you used "may" be optimized for CCTV cameras hence the UV blocking.

As I mentioned earlier, the particular 4mm lens you installed the filter on provides the luxury of a very wide lip of about 2.5mm around the rear lens element which makes it possible to apply "the glue blobs on the filter and to the side only". Most lenses provide little or no lip around the lens element at all and therefore are much more challenging. The 6mm ƒ/1.2 lens I bought from Treeye requires a round IR cut filter that is 12mm in diameter which is the width of the threaded barrel. (hence "M12" lens). The lip around the rear lens element is only about 1mm wide. A different style 6mm ƒ/1.2 lens I bought from Yumiki appears to have an even narrower lip. Any gluing job will require extreme precision and the cement must go between the filter and the lens barrel as there is no room for "side only" gluing.
 
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Well, I haven't actually installed the IR-cut filter on a lens and used it in everyday normal service yet, so perhaps hold off saying, "it worked for you". :nailbiting: While I'm not expecting any problems and as far as I can tell, Lazer Bond should be a good solution, you never know. :geek: If you try it too, I'll be very interested in learning of your experience.

Interesting link!

I believe your glue pen will work just fine, because of the manufacture using his glue and light prescription, the only possible thing I imagine going wrong could be the glue not working with metal, some don't some do, it might tell you on the package whether it does or not! Remember that most of these glues are designed for working with the glass or plastic lenses themselves, that's why some don't work with metal, which we need.
It goes without saying, as much as you have helped me you will get any news/recommendations I find, that link I gave above is full of things I couldn't/didn't find anywhere else, so it is definitely a must read.

When Radius said be sure to minimize the amount of glue in areas that light can't get to because it might not cure, is not exactly right. Most of these glues now have not only light curing properties but heat curing properties as well because of areas that light might not reach well. There's always the chance that that some manufactures didn't include the heat curing substance to his recipe though. As always if in doubt email them with any questions before committing yourself to information you don't see on the product package.

It has become really amazing to me in researching this subject of light for lens curing. I had no idea light had so many interactions with the universe and how we perceive things in it. I'm not talking just the visible spectrum (400 to 700nM roughly) either o_O:cool:.
 
I finally got around to installing the IR-cut filter on my 2.8-12mm ƒ/1.2 Varifocal. So, now I may have to change the title of this thread from "Mobius Varifocal Zoom IR" to "Mobius Varifocal Zoom IR-Cut!" :D

The filter installation went well but it was quite a bit more challenging than I was anticipating, as I will explain. One thing I can say is that the Lazer Bond UV adhesive works beautifully and I can now wholeheartedly recommend it as the go-to low cost optical filter cement. I'm convinced at this point that it's the same expensive stuff you can buy elsewhere, only packaged in a small convenient form for the average consumer. There is just no good reason to mess around with any other kind of "glue" or silicone product for mounting optical filters when you can use this water clear UV cement that allows you to carefully position your work and then secure it instantly with a fully cured inert bond.

The tricky part about installing a rear filter on this particular lens is that there is no room to apply the cement along the edges of the filter. The adhesive must be applied between the glass filter and the metal rear lens retaining ring which fortunately is wide enough that it gives you some room to work with. So, the challenging part here was that even the tiniest pin-point blob of glue I could apply (I practiced first on two pieces of glass) will spread out more than you might expect or want under the IR-cut filter once you "press" it into place on the rear of the lens. There was a real risk that some of the cement could bleed out onto the rear element of the lens or even worse, that the cement could touch the inner wall of the lens tube, thus rendering the lens unfocusable once the cement is cured. The filter itself is 9.5mm in diameter and the lens tube inner diameter is 10.5mm so there was not much wiggle room to work with. At one point I was working the focus mechanism in and out before curing the cement so I could be sure there was no glue on the inner wall of the tube. Finally, once I was satisfied with my glue job I hit it with the UV LED light and a few seconds later the job was all done and I'm very pleased with the results!

lens2.jpg

lens3.jpg

So, I did a quick, rudimentary focus job inside my office today just so I could test out the lens and everything is looking pretty good! I'll likely need to reset the focus point to optimize it for car distances out on the road and then tweek the advanced settings in mSetup to optimize. One thing I did here was to change out the threaded lens mount on the module and adjust it to eliminate the left side lens alignment/out-of-focus issue I discovered previously that can be seen in this image.

Here's a screen shot from today's first test. I'll provide some updates as I continue to experiment.
IRcut_test.jpg
 
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Also, remember to minimize the amount of adhesive in areas that the light cannot penetrate as it may not cure. The IR filter I installed also seem to cut UV light that is why I applied the glue blobs on the filter and to the side only.

While I certainly agree with the general advice to avoid applying UV cement where UV light cannot penetrate, I just want to report that I encountered no such problem with the IR-cut filter I installed in the varifocal 2.8-12mm. The UV light source penetrated this particular IR filter without any issues.
 
I believe your glue pen will work just fine, because of the manufacture using his glue and light prescription, the only possible thing I imagine going wrong could be the glue not working with metal, some don't some do, it might tell you on the package whether it does or not! Remember that most of these glues are designed for working with the glass or plastic lenses themselves, that's why some don't work with metal, which we need.
It goes without saying, as much as you have helped me you will get any news/recommendations I find, that link I gave above is full of things I couldn't/didn't find anywhere else, so it is definitely a must read.

When Radius said be sure to minimize the amount of glue in areas that light can't get to because it might not cure, is not exactly right. Most of these glues now have not only light curing properties but heat curing properties as well because of areas that light might not reach well. There's always the chance that that some manufactures didn't include the heat curing substance to his recipe though. As always if in doubt email them with any questions before committing yourself to information you don't see on the product package.

It has become really amazing to me in researching this subject of light for lens curing. I had no idea light had so many interactions with the universe and how we perceive things in it. I'm not talking just the visible spectrum (400 to 700nM roughly) either o_O:cool:.

@Lola, I was re-reading your post above about some UV cements not working on metal. Lazer Bond seems to work fine on metal, glass and plastic too! :)
(Some UV cement may not work well with polypropylene or polyethylene plastics apparently.)

lazerbond2.jpg

Also, I found another brand of UV cement on Amazon that comes with a 12 gram refill (correction: 8 gram refill along with the 4 gram pen) at a very reasonable price. (12 bucks). I may buy some and try it out on other types of larger projects and repairs just to see how well it works. I like the idea of having an alternative to Cyanoacrylate (Super-glue) without the vapors and other hassles such as getting it on your finger tips. Although Visbella bonds almost instantly when UV light is applied they also mention that full cure takes ten hours. I wonder if that fact applies to the other UV cements as well? It would make some sense that the molecular process that is triggered with UV light might continue to unfold as with other chemical hardening polymer adhesives such as epoxy glue.

https://www.amazon.com/gp/B0744K9TRW
visbella.jpg
 
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@Lola , yes indeed that many UV-cure glues can also be heat cured (including the one I used, but it needed > 100 C). That being said, the reason to us a UV-cure glue is that it can be instantly set, at least to the point where spreading of the glue to places you don't want it is not an issue. If you were anyway going to heat cure your adhesive then why bother using a UV-cure one in the first place?

Here's another alternative, though more costly (15-20 USD) than what has been posted above:
Bondic

@Dashmellow , polypropylene, polyethylene (commonly used for packaging of foodstuff), ETFE etc... are low energy surfaces and are difficult to bond with adhesives. There are some specialized glues (that are $$ like 50 USD/tube and nasty) for these material. I was told that the surface PP and PE can be treated via various means including flame, corona discharge, plasma ... in order to make them compatible with adhesives and printing inks such that the surface can be properlly wetted with the bonding agent.

The Bondic stuff claims that it can be used to attach PP or PE but I think it is only via mechanical means. That is, the surfaces to be attached need to be roughened and the glue needs to penetrates into these surface features, forming a bridge to the other surfaces. That is different than adhesives that form molecular bonds with surfaces such as what would happen when the above mentioned treatments are used. With the proper choice of adhesive, a true molecular bond (adhesive-substrate) can be had and that interface can be stronger than the bulk material itself.
 
I have a strong hunch that all of these consumer level UV adhesives are essentially the identical substance regardless of price. I'll bet if they were tested side by side there would be no difference in performance.

One often has to be very careful with how things are packaged, priced and marketed. Last summer, I was at a local plant nursery where I came upon some "Crystal Clear & Pure" Hummingbird food selling at $8.99 for a small package of white granules in a fancy package. In tiny print on the back of the package it said, "Ingredients: sucrose".
 
I have a strong hunch that all of these consumer level UV adhesives are essentially the identical substance regardless of price. I'll bet if they were tested side by side there would be no difference in performance.

One often has to be very careful with how things are packaged, priced and marketed. Last summer, I was at a local plant nursery where I came upon some "Crystal Clear & Pure" Hummingbird food selling at $8.99 for a small package of white granules in a fancy package. In tiny print on the back of the package it said, "Ingredients: sucrose".

Exactly, you hit the proverbial nail right on the head:cool:
 
The cost is in the "certification". Of course, we'll never know for sure of the actual differences between name brand and generic, short of running a full chemical analysis. Most of these things are proprietary in composition. Still I would trust 3M over some no-name for anything critical.

...
One often has to be very careful with how things are packaged, priced and marketed. Last summer, I was at a local plant nursery where I came upon some "Crystal Clear & Pure" Hummingbird food selling at $8.99 for a small package of white granules in a fancy package. In tiny print on the back of the package it said, "Ingredients: sucrose".
:):):) genius marketing.

On the same note, next time you read a food label, Dextrose = glucose.
 
@Lola, I was re-reading your post above about some UV cements not working on metal. Lazer Bond seems to work fine on metal, glass and plastic too! :)
(Some UV cement may not work well with polypropylene or polyethylene plastics apparently.)

View attachment 36539

Also, I found another brand of UV cement on Amazon that comes with a 12 gram refill at a very reasonable price. (12 bucks). I may buy some and try it out on other types of larger projects and repairs just to see how well it works. I like the idea of having an alternative to Cyanoacrylate (Super-glue) without the vapors and other hassles such as getting it on your finger tips. Although Visbella bonds almost instantly when UV light is applied they also mention that full cure takes ten hours. I wonder if that fact applies to the other UV cements as well? It would make some sense that the molecular process that is triggered with UV light might continue to unfold as with other chemical hardening polymer adhesives such as epoxy glue.

https://www.amazon.com/gp/B0744K9TRW
More then likely the ones with UV light cure also have some of the heat cure type agent in the prescription, it's important to the manufactures that their product works, regardless, therefore providing the reason for the included light source with the proper wave length to cure the product. Not all heat agents require a high heat source to cure over time. Their are some products that are cured with heat (or both agents) only but they are basically used only by big companies that work on 100's if not 1000's of lenses, they use special heat ovens that are very expensive.
The UV cements have cure times all over the place from short to long and varies a lot by manufacture, strange, but that's the way it is! The biggest enemy of the UV curing agents is the shelf life of the products, they run from about a few months to somewhat over a year, and the time period starts from the day of making the stuff. For example if you bought some the guarantee to you would be from the day you bought it plus how long since it was mixed at the factory, that's a little something they forget to tell people!



View attachment 36540
 
I've been exploring what can be done with this Varifocal lens since I installed the IR-cut filter. Recently, I've been doing some experiments with close-up video and still photography observing various species of woodpeckers and other birds that visit the suet feeder out on my deck. This project is basically in preparation for some upcoming Spring workshops I'll be conducting at a local environmental education center where I work with kids using the Mobius action camera (and others) to observe and record wildlife behaviors while teaching them about photography, video, computers, etc.

This Varifocal 2.8-12mm ƒ/1.2 has proven itself to be an amazingly versatile lens. I've been finding it to be an excellent telephoto dash cam and often find it superior to some of the fixed telephoto lenses some of us have been experimenting with. I'm finding the ability to quickly change focal lengths or focus the lens without having to dismantle the camera to be a real boon. I'll usually focus the lens using web cam mode on my computer but one can also adjust focus on the spot in the field using a small video monitor. It's no big deal to go from doing close-up work like this with the camera to having it back in my truck as a dash cam within minutes. For wildlife video, it's especially useful to be able to change lens settings or make adjustments on the fly. Probably the biggest challenge to shooting close-up with this type of set-up is that you don't get much depth of field to work with and it's helpful to be able to make changes easily as it's all too easy to end up with out-of-focus imagery.

With the abysmal bandwidth I'm stuck with out here on the fringes it's difficult and very time consuming to upload much video, so mostly I'll just post still frames but here's a short clip of a male Hairy woodpecker (Leuconotopicus villosus).


Here is a female Hairy Woodpecker (Leuconotopicus villosus).
female_hairy.jpg

hairy4.jpg

Red-bellied woodpecker - male (Melanerpes carolinus)
redbelly.jpg

Here's the set-up I used for mounting the camera. Interestingly, when I covered the equipment with camouflage material the birds were afraid of it and wouldn't come near but when I just put the camera, mount, monitor tripod and even a reflector out there bare, they had no problems with it. In fact, one of the biggest problems was having birds land on the camera or the cables as if they were branches of a tree to perch on. One bird even took a poop on the camera! :yuck::LOL:

set-up3.jpg

set-up1.jpg

powerbank.jpg
 
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I've been exploring what can be done with this Varifocal lens since I installed the IR-cut filter. Recently, I've been doing some experiments with close-up video and still photography observing various species of woodpeckers and other birds that visit the suet feeder out on my deck. This is basically in preparation for some upcoming Spring workshops I conduct at a local environmental education center where I work with kids using the Mobius action camera (and others) to observe and record wildlife behaviors while teaching them about photography, video, computers, etc.

This Varifocal 2.8-12mm ƒ/1.2 has proven itself to be an amazingly versatile lens. I've been finding it to be an excellent telephoto dash cam and often find it superior to some of the fixed telephoto lenses some of us have been experimenting with. I'm finding the ability to quickly change focal lengths or focus the lens without having to dismantle the camera to be a real boon. I'll usually focus the lens using web cam mode on my computer but one can also adjust focus on the spot in the field using a small video monitor. It's no big deal to go from doing close-up work like this with the camera to having it back in my truck as a dash cam within minutes. For wildlife video, it's especially useful to be able to change lens settings or make adjustments on the fly. Probably the biggest challenge to shooting close-up with this type of set-up is that you don't get much depth of field to work with and it's helpful to be able to make changes easily as it's all too easy to end up with out-of-focus imagery.

With the abysmal bandwidth I'm stuck with out here on the fringes it's difficult and very time consuming to upload much video, so mostly I'll just post still frames but here's a short clip of a male Hairy woodpecker (Leuconotopicus villosus).


Here is a female Hairy woodpecker.
View attachment 37051

View attachment 37052

Red-bellied woodpecker - male (Melanerpes carolinus)
View attachment 37053

Here's the set-up I used for mounting the camera. Interestingly, when I covered the equipment with camouflage material the birds were afraid of it and wouldn't come near but when I just put the camera, mount, monitor tripod and even a reflector out there bare, they had no problems with it. In fact, one of the biggest problems was having birds land on the camera or the cables as if they were branches of a tree to perch on. One bird even took a poop on the camera! :yuck::LOL:

View attachment 37056

View attachment 37055

View attachment 37062
Did you use motion detection, or record continuously? Was the flying blue jay a still photo or a video frame?
 
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