SJCAM SJ8 for NIGHT VISION? Please help

Nigel

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Hello again guys! After thinking a lot about your advices, it looks like the best option will be to buy the gitup F1 and remove the IR filter. You said that it will be easy to replace, right? That means that I could use a lens for day and another lens for night and easily mount the IR lights. Am I right? I never did anything like that to a camera, so I think that this will be the best choice for a newbie
I don't think I would want to change the lens in the F1 every day, I'd get two F1s if that was necessary, but it would be possible. Basically you unscrew your daytime lens and screw in the IR lens. The main difficulty is in focusing it, you would need to screw it in maybe 20 turns and then set it accurately against some marks you have previously drawn on it. Screw it in too far and you may damage the sensor, and do it often and you may get dust on the sensor, so a bit of care is needed.

The first time you do it, you will need to disassemble the camera and remove the glue that holds the lens in place (stops it unscrewing). Mine had some rather solid glue on, may be a bit more difficult than instructions you find on Youtube etc. but with a bit of care is possible. Actually I left the glue on and just used a sharp knife to cut around the join between the glue and the mount, that way when I screw it back in I just screw it in until it hits the glue and stops, then it is in focus.

I suggest a second lens for the IR, removing the IR filter from the standard lens is likely to be a one way task unless done with a lot of care and solvents. If you don't mind a bit of vignetting just get any M12 lens designed for IR, standard lenses generally don't focus IR light very well so one designed for IR should be better. Remember that the sensor is bigger than most, thus you want a lens that gives a bigger image than most or else you loose the corners. The F1 is 4K so loosing a bit of resolution in the corners probably isn't an issue for IR since you wont have best quality in low light anyway, just crop the image and resize to 1080.

P.S. When you disassemble the F1, be very careful of the wifi antenna, otherwise you can damage the antenna as the case comes apart, it can be unplugged from the main PCB to avoid damage after separating the case.
 

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Yes you cant really swap lens on cameras like this, they are screwed in place so you have to manually find the focus every time.
It is easy to swap lens on a regular camera as they have a twist / lock attachment so it automatic end in the right position, the 12 mm fine thread lenses these are screw in, and when you get near the focus sweet spot it take just a few degrees turn of the lens to be off focus again.

As i recall the F1 dont have a HDMI plug so connecting it to a TV when doing focus are not possible, so you will have to do it with the live view in the APP i assume ( dont have a F1 myself )
 
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elchivatto

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Oh well, thank you again Nigel and kamkar1! :):):)
Actually there's no problem if I'll use this F1 only for IR shooting, and another camera for daylight, because it's preferable for me not to play too much and damage the cam :ROFLMAO::ROFLMAO::ROFLMAO:
What I need is at least 1080p well focused and a medium angle like 120º (in GoPro it's called "medium FOV") or with the FOV enough for selecting that medium option in the camera app.
So do you think it will be easy to find that lens? Of course would be great not to have vignetting, so if I find a lens with near the same FOV than the original, and cut it to "medium" by the app, would be great for me.
 

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@elchivatto, the proper and easiest way to remove an IR-cut filter from the back of an M12 action camera lens is to gently apply some heat using a heat gun or hair dryer. This will soften the UV activated cement that was used to attach it at the factory. Don't use any solvents or try to pry or force the thin glass filter off the lens or you risk damaging your lens.

Once the filter is warm enough it will come right off with a little help using an X-Acto (craft) knife applied under the edge or it may just fall off by itself if you turn the lens upside down. Be careful not to overheat the lens or filter. Wear nitrile gloves during the process so that when you handle the filter you can put it away safely in a small zip-lock bag for possible future use. (You can re-attach the filter to this lens or a different lens using some readily available UV cement if you ever want to for another project or to return the lens to its original condition.)
 
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elchivatto

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Thank you dashmellow. What do you think about the FOV I need? I think that maybe the lens are very cheap in China, so I could save the original lens without touching it, and buy another without IR filter. But it's preferable for me not to have vignetting when using the "medium FOV"
 

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Thank you dashmellow. What do you think about the FOV I need? I think that maybe the lens are very cheap in China, so I could save the original lens without touching it, and buy another without IR filter. But it's preferable for me not to have vignetting when using the "medium FOV"

Not sure what focal length to suggest at the moment for your needs. I'll need to think about that a bit. The Treeye store on AliExpress is an excellent and reliable source for quality action camera replacement lenses and the prices are reasonable. They will supply lenses with or without an IR-cut filter installed if you request it. The folks who run the store are very helpful and you can contact them before purchase if you need assistance.

https://treeyelens.aliexpress.com/store/725056?spm=2114.10010108.0.0.23904c8cpmkLxb
 
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Nigel

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As i recall the F1 dont have a HDMI plug so connecting it to a TV when doing focus are not possible, so you will have to do it with the live view in the APP i assume ( dont have a F1 myself )
You can use the FPV analog video output, but a tablet with the wifi app is probably the best, and if you have a computer available then you can play the live view on a monitor/TV in your normal video player over wifi using the rtsp:.

Oh well, thank you again Nigel and kamkar1! :):):)
Actually there's no problem if I'll use this F1 only for IR shooting, and another camera for daylight, because it's preferable for me not to play too much and damage the cam :ROFLMAO::ROFLMAO::ROFLMAO:
What I need is at least 1080p well focused and a medium angle like 120º (in GoPro it's called "medium FOV") or with the FOV enough for selecting that medium option in the camera app.
So do you think it will be easy to find that lens? Of course would be great not to have vignetting, so if I find a lens with near the same FOV than the original, and cut it to "medium" by the app, would be great for me.
The standard lens is probably too wide for you, cropping the centre 1080 section of the image might be closer, probably somewhere in between and then resize to 1080 will give good results, but I suggest getting an IR lens without IR filter with a slightly wider FOV than you want and then cropping the result a bit, then you don't need to worry about loosing the corners. An IR lens that gives a large enough image to avoid loosing the corners may be hard to find since the sensor is larger than normal.
 

Nigel

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@elchivatto, the proper and easiest way to remove an IR-cut filter from the back of an M12 action camera lens is to gently apply some heat using a heat gun or hair dryer. This will soften the UV activated cement that was used to attach it at the factory. Don't use any solvents or try to pry or force the thin glass filter off the lens or you risk damaging your lens.

Once the filter is warm enough it will come right off with a little help using an X-Acto (craft) knife applied under the edge or it may just fall off by itself if you turn the lens upside down. Be careful not to overheat the lens or filter. Wear nitrile gloves during the process so that when you handle the filter you can put it away safely in a small zip-lock bag for possible future use. (You can re-attach the filter to this lens or a different lens using some readily available UV cement if you ever want to for another project or to return the lens to its original condition.)
How warm do you have to get the filter for it to "come right off"?

Those 4K sensors get hot in use and the F1 is designed to sit in the sun for use as a dashcam so I guess the glue is designed for over 100 degrees C?
 

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How warm do you have to get the filter for it to "come right off"?

Those 4K sensors get hot in use and the F1 is designed to sit in the sun for use as a dashcam so I guess the glue is designed for over 100 degrees C?

I've never measured the actual temperature required to facilitate the removal of the IR filter but you do indeed need to get it fairly hot. In some cases IR-cut filters are attached directly to the CMOS, not the lens so it can indeed endure some heat.
The UV cement is a polymer that is softened by heat. Solvents don't work and using mechanical force risks breaking the filter and leaving behind shards of glass. I suppose it is conceivable (but I think unlikely) that the F1 uses a higher temp UV cured cement variant than other lenses but nevertheless applying heat would still be the best method for removing an IR-cut filter from a lens. I use a heat gun because I find it better to apply the heat slowly but some people even use a torch which is much faster but risky. Either way, the filter will come right off. Usually it requires a little help from a sharp blade on the edge for leverage but the filter can indeed just pop off by itself once the cement is soft enough.

 

Nigel

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I've never measured the actual temperature required to facilitate the removal of the IR filter but you do indeed need to get it fairly hot. In some cases IR-cut filters are attached directly to the CMOS, not the lens so it can indeed endure some heat.
The UV cement is a polymer that is softened by heat. Solvents don't work and using mechanical force risks breaking the filter and leaving behind shards of glass. I suppose it is conceivable (but I think unlikely) that the F1 uses a higher temp UV cured cement variant than other lenses but nevertheless applying heat would still be the best method for removing an IR-cut filter from a lens. I use a heat gun because I find it better to apply the heat slowly but some people even use a torch which is much faster but risky. Either way, the filter will come right off. Usually it requires a little help from a sharp blade on the edge for leverage but the filter can indeed just pop off by itself once the cement is soft enough.

I worry about doing that because these days some of the lens elements can be plastic aspheric elements and getting them that hot may not be good for the plastic!

Although we seem to be loosing the plastic elements again now that they have worked out how to make cheap moulded glass aspheric elements.

I have removed a UV filter by force before and shards of glass are not an issue, the glass is very thin and can easily be turned to powder by crushing it with pliers, after which a vacuum cleaner/air blower will remove it all (keep the sensor in a sealed dust free box while doing this), of course it is a one way process then.
 

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I worry about doing that because these days some of the lens elements can be plastic aspheric elements and getting them that hot may not be good for the plastic!

Although we seem to be loosing the plastic elements again now that they have worked out how to make cheap moulded glass aspheric elements.

I have removed a UV filter by force before and shards of glass are not an issue, the glass is very thin and can easily be turned to powder by crushing it with pliers, after which a vacuum cleaner/air blower will remove it all (keep the sensor in a sealed dust free box while doing this), of course it is a one way process then.

"Shards of glass are not an issue", so resort to crushing with pliers? Vacuum cleaner? Dust free boxes? I don't know Nigel, this all sounds rather questionable to me, especially when there is such a simple, clean and efficient method available.

If a camera is using cheap plastic lens elements I would probably tend to avoid it. Only the cheapest of dash cams I've ever owned use them. In any event, the chance that one may encounter anything the can be damaged by heat is the reason I prefer to use a heat gun rather than a torch so you have greater control over how much heat you are applying and how quickly.
 
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elchivatto

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Hey guys, talking about all this things, I have a GoPro hero 4 right now, but it looks like it's different from another cameras. Do you know if it possible to do the same with this specific model? I mean, to remove the IR filter and using it like a night vision cam with an IR flashlight. I saw that the people use special cases for doing this, but it's expensive and I don't understand if it's necessary or not. Did you tried with this camera?
Anyway, maybe will be better to use the gitup F1, as you said before, but I could try with the GoPro (if it's easy) and see what happen... Or don't worth it?
 
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elchivatto

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Ah!!! Another important question! I saw videos where the camera looks like to has a hybrid IR cut, because it sees normal color with daylight, but also good in dark using an IR flashlight without changing to black and white. I mean, that cameras are clearly not full spectrum, but maybe near IR or something. How they do that? That's would be great option, because if the camera could be used in day, and also in dark with IR lights will be the best choice for me.
 

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Hey guys, talking about all this things, I have a GoPro hero 4 right now, but it looks like it's different from another cameras. Do you know if it possible to do the same with this specific model? I mean, to remove the IR filter and using it like a night vision cam with an IR flashlight. I saw that the people use special cases for doing this, but it's expensive and I don't understand if it's necessary or not. Did you tried with this camera?
Anyway, maybe will be better to use the gitup F1, as you said before, but I could try with the GoPro (if it's easy) and see what happen... Or don't worth it?

Yes, you should be able to remove the IR-cut filter from a GoPro Hero 4. In this video the guy just swaps lenses for one that passes IR but you can simply remove the filter as explained above. It also wouldn't be hard to do a nicer, cleaner job of things than this fellow does but it's an example of the sort of thing you wish to accomplish.

 
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Dashmellow

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Ah!!! Another important question! I saw videos where the camera looks like to has a hybrid IR cut, because it sees normal color with daylight, but also good in dark using an IR flashlight without changing to black and white. I mean, that cameras are clearly not full spectrum, but maybe near IR or something. How they do that? That's would be great option, because if the camera could be used in day, and also in dark with IR lights will be the best choice for me.

What you are describing is a camera with a mechanical IR-cut filter. Most CCTV cameras are built with them so they can see normal colors during the day and then switch to B&W IR illuminated night vision after dark.
They accomplish this with a little mechanism that holds the IR-cut filter in the path of the lens during that day and switches it out of the way at night. The camera has a photo diode that detects when the sun has set and the light level has dropped to a certain point (usually around .5 LUX) and at that point an electrically operated solenoid pulls the IR filter out of the way. When the sun comes up the next morning the solenoid moves the IR filter back into the light path behind the rear element of the lens.

The mechanism looks like this:

IRcut.jpg

Some CCTV cameras now do this digitally with less of a B&W effect at night but I'm not aware of a full color night vision camera nor do I think such technology is available in an action cam.
 
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elchivatto

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Thank you Dashmellow, but that's not what I was talking about, maybe I didn't explain it well. I saw that some normal cameras could see some of the IR light, not everything but enough for viewing in low light with a IR flashlight. Looks like cameras like those, not block the entire IR lights, so you can see in color, and also IR at the same time. The G1S specifications says that it can see "near" infrared light. Maybe that's what I was talking about, sorry for my ignorance.
You know, maybe the G1S would be great for me, but it only has 1080p 30fps, that's why I was asking (and bothering) about modify another camera like the F1 for having more resolution and fps.
I was searching about the Sony starlight sensor, and it looks very interesting, because it can record "color night vision". I would love to have a camera with this capabilities, because I'll not be in complete dark, but in very low light and with a help of an IR flashlight. I would buy the G1S without any doubt, but I'm bothering you, because maybe it's possible to find a better option, and you are the experts!
Would be great to have a camera with starlight sensor for "color night vision"... Looks like there are some CCTV cameras with 1080p 60fps like this:
https://m.aliexpress.com/item/32815928932.html
They say that you could DIY using this parts, but I don't understand so much. Do you think that is possible to assemble a portable camera using this sensor?
 

Dashmellow

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Thank you Dashmellow, but that's not what I was talking about, maybe I didn't explain it well. I saw that some normal cameras could see some of the IR light, not everything but enough for viewing in low light with a IR flashlight. Looks like cameras like those, not block the entire IR lights, so you can see in color, and also IR at the same time. The G1S specifications says that it can see "near" infrared light. Maybe that's what I was talking about, sorry for my ignorance.
You know, maybe the G1S would be great for me, but it only has 1080p 30fps, that's why I was asking (and bothering) about modify another camera like the F1 for having more resolution and fps.
I was searching about the Sony starlight sensor, and it looks very interesting, because it can record "color night vision". I would love to have a camera with this capabilities, because I'll not be in complete dark, but in very low light and with a help of an IR flashlight. I would buy the G1S without any doubt, but I'm bothering you, because maybe it's possible to find a better option, and you are the experts!
Would be great to have a camera with starlight sensor for "color night vision"... Looks like there are some CCTV cameras with 1080p 60fps like this:
https://m.aliexpress.com/item/32815928932.html
They say that you could DIY using this parts, but I don't understand so much. Do you think that is possible to assemble a portable camera using this sensor?

OK, now I understand better what you are getting at. The CCTV cam module you linked to is unfortunately not viable (at the moment) for what you want. Keep in mind that CCTV cams like that are designed to work from a fixed position facing a static location like a parking lot or warehouse at night. Even with the "starlight" sensor that can see better in low light they still use IR illumination. Also, keep in mind that most CCTV cameras including the one you linked to require a 12 volt power supply, not 5 volts like an action camera. More importantly, CCTV cams require a separate DVR with a hard drive to record what they see. So for now, yes, "it would be great" to be able to record in the forest in the dark @1080p 60fps but I don't think it possible with any currently available action camera.

I think if you choose the right action camera and remove the IR cut filter you will have what you require but it will be 30fps. A good floody IR torch should be a suitable light source.
 
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Dashmellow

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Ok thank you! It's decided, buy the F1!
Thank you for all your advices!
:D:D:D:D

Sounds like a good choice! Now you've got to find a good, powerful, floody IR flash light (or two) unless you already have one.

BTW, @elchivatto, just about a year ago I did a lot of experimentation with an IR (zoom) lens on a Mobius action camera, including using it at night with IR illumination from the output of an old CCTV camera. The Mobius is not a camera known for fantastic low light performance but the results all in all were pretty good doing some wildlife video of foxes. You may find it interesting along with parts of the rest of the thread. https://dashcamtalk.com/forum/threads/mobius-varifocal-zoom-ir.30602/post-366580
 
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elchivatto

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Thank you again. Oh, do you remember that you said that would be great having a F1 modified for night, and another camera for daylight? So, I was checking out the new GoPro hero 7 for daytime, but apart from it's new stabilization, it still looks like a ****ty camera in places without sunlight, for example inside a building with artificial illumination, what do you think? Because most of the time I'm inside places without sunlight, so maybe I'll bought 2 F1 instead of 1 and the GoPro, and use one for normal situations and the other for night with IR lights. I don't need too much stabilization anyway, what I need most is a good sensor for different types of light, specially artificial lights.
 
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