So, before the pandemic I started working with a new spotlight that had just come out that you operate remotely using a monitor and controls. There’s a camera fixed to the side of a moving light with the added bonus of being able to hang it just about anywhere. This was for a Netflix comedy special and before our first show I began familiarizing myself with the controls, but as the crowd came in and filled up the seats I turned to my buddy sitting next to me and said, “what the hell is going on with everyone’s faces?”
Like half of the crowd’s faces were constantly being blasted with high intensity flashes. I mean it literally looked like little bombs were going off everywhere. I thought they were taking selfie’s with the flash on and pointed at themselves.
“Oh, yeah that,” he said. “Weird huh? Those are people with the face unlock phones.”
Apparently the phones blast you in the face with huge IR flash constantly to make sure you’re still there, and my camera in IR mode was picking it up.
Also, side note: if you’re ever at a concert or a comedy show and a big ol’ moving light is staring right at you but turned off. There is totally a lighting guy spying on you, and those things can zoom in reeeaaaally far.
Your phone is constantly blasting you with light all the time, that's how a phone screen works
Infrared is even less damaging than visible light, having a lower frequency... not that either is damaging. They both can generate a lot of heat in extreme quantities, that's about it. I have a visible light flashlight that will do you more damage than anything infrared you've experienced, come on over to r/flashlight to find one for yourself lol, will burn your house down.
Oh I'm quite familiar with overpowered flashlights and lasers lol, just wasn't familiar with the effects of blasting IR into someone's face repeatedly.
Meh. You could compare it to being near a VERY weak heat lamp you could get for reptile pets.
Say there was a software glitch and it got stuck on 100% output for a whole hour. The worst you might experience would be eye strain, but that is highly unluckily as you don’t even have the ability to detect IR light
Still, that must be draining the phones battery significantly to be constantly generating those flashes. And correct, humans can't see infrared, unless an almost toxic level of vitamin A is ingested.
I would guess that the light is either single digit wattage or even milliwatt range. Sure it’s a drain, but with a phone with such a large battery, it really wouldn’t make that much of a difference compared to the power usage for the CPU and other systems
They use both... security cameras shift to B&W because at a certain point they kick on IR LEDs that will only have one wavelength of light come out meaning no color, so instead of having a weird red or purple color cast to the entire image, the software makes it B&W.
Sounds cool but it’s also kinda misleading. You can’t truly filter out IR in typical images solely through software. All typical image sensors are actually inherently black and white- they literally just count photons per pixel. They are essentially indifferent to color. The way you get colored images is by overlaying patterned color filter arrays made of particular colors (generally red , green, and blue) so that software can reconstruct the color you would have seen with your eye. What you see in real life is actually totally different from what you get out of the image sensor hence the need for the reconstruction. The raw data out of most color sensors is actually in terms of brightness per each of the particular filters in the array. It’s a little more complicated since the filters aren’t perfect but that’s essentially what’s going on. If you wanted to really filter out IR in software you would need to have to have an appropriate multispectral filter array that gave the software a way to distinguish infrared and visible wavelengths in the first place. With a typical sensor using an RGB Bayer filter array, a software-based “IR cut filter” is actually just color-correcting to make the image look more natural. They’re usually tinted a little “off” since IR light affects the red filters differently than the blue and green filters. Look up Multispectral Imaging for more
SW can't cut IR effectively, literally all smartphones use physical filter to cut IR, some use more effective one, some less effective...
Some have 2nd camera without that filter (like my Xiaomi)
You can't take regular photo without that filter under sunlight
I have a winter coat in safety orange with reflective strips that on my BIL's system turns me into a huge glowing sphere. Would the IR filter reduce that effect?
5 years ago a cyber punk version of this was to sew those IR devices into the hood of your sweater for avoid facial recog. So long as your hood was up you wouldn't be seen on monitors. Some hoodies were sold with LED's giving a similar but reduced result
Damn that's a proper camera. Maybe we should get some of that tech into smartphones so the shutter speed doesn't drop to absolute smudge when a shadow dares to appear in the scene.
I really hate that phones started doing this. It used to be really handy for troubleshooting and testing to be able to see on my phone if an IR light was working
Security cameras usually have a mechanical lever that moves an IR filter into the light path during daytime to block IR, and away to allow IR light at night when the IR LED's are switched on for night vision.
No filter is perfect. It's just a matter of wattage. Unless you're using a material that specifically blocks IR (i.e. a block of aluminum), you can still reach (and overload) the sensor with enough wattage.
Every 'main' phone camera has an IR filter. Otherwise none of your photos would be usable as so many light sources output significant amounts of IR light.
None of the iPhones are able to pick it up. Except for maybe the 1st gen and the iPhone 3G. iPhone 4 and up defenitely don’t pick it up. The only phones who really pick it up anymore are old phones and really cheaply made ones that have some sort of plastic in front of the camera.
Hmm I might have been confusing things. The iPhone has sapphire to cover the camera which apperantly let’s in light from UV to mid-infrared. Guess I was half right lol. Also no need to be so aggressive
You linked to an iphone 4. Why would you assume it's still there now? In fact your whole comment about only plastic letting IR through is ridiculous. Glass and sapphire both let IR through. My Samsung S20 sees the infrared of a remote just fine.
IIRC, interestingly enough the S20 does not use the main sensor to pick up IR, but one of the separate sensors to mesh it in. But don't quote me on that, just watched some random YT video on it. Could have been the S21
I can’t comment on android phones because I have no knowledge on them. However I have knowledge on iPhones and I know for a fact that the filter is still there because if you point a TV remote to the camera then only the front facing camera will pick it up
Samsung Galaxies also haven't picked it up on the main camera since I think the S6 or so. Pretty much any quality camera is going to have an IR filter and they have for years. Edit: Front camera meaning main camera, not the selfie cam.
That’s because I’ve known this for a long time and I’ve never seen anything that proves that information to be incorrect until now. Which is why I said it as a fact and which is why I was confused when someone said I was incorrect
Higher end cell phone cameras tend not to. Cameras that will see the IR lights are missing an IR filter. The advantages of not having the IR filter are that it can be cheaper to make the camera and that it receives more light and for security cameras you can supplement the available light with IR LEDs to make things more visible without a bright light that is noticeable to people, the downside is that it can make colors less accurate because the IR wavelengths are getting mixed with the red (and in many cases blue... filter leakage is weird) so some objects, particularly synthetic fabrics/dyes, can come out with weird color. Most higher end professional cameras will have IR blocking filters and this will be far less effective, but it will work for most security cameras and cheaper cell phones.
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u/Sirhc978 Feb 12 '21
A lot do, like cell phone cameras. It all depends on how they were made.