The weird, invisible world of infrared

[@jtapia1123]

I’m here after Dune 2 🫡

[@NoName-fp2nd]

steve mould gang

[@DrAndrewSteele]

Hi gang! I’ve not uploaded for a while because I’m writing a book (turns out writing a book takes ages!) but if you like this please do subscribe and I promise to make some more science videos ASAP. Some may even be as good as Steve’s… :)

[@NoName-fp2nd]

Subscribed.

[@someone-fk7bi]

And one more

[@DZHOY]

and another

[@phyphor]

And my axe!

[@R2D2internet]

2:26 It's true that IR travels slightly deeper into skin, look at the veins on the arms!

[@DrAndrewSteele]

If you want to see some seriously veiny arms… instagram.com/p/BzBtp0BB9wn/

[@oscarfeatherstone6688]

That bit when the tube pulls into the station was awesome.

[@DrAndrewSteele]

Oscar Featherstone I didnʼt expect it to be so amazing underground, but it really was!

[@oscarfeatherstone6688]

So was this shot with a dedicated IR camera, or did you remove the IR filter from a modified DSLR?

[@DrAndrewSteele]

It was a DSLR with the filter replaced with fused silica, which passes IR, visible and UV…and then an IR filter on the front of the lens to block the other two. Visible footage was with an unmodified one. :)

[@oscarfeatherstone6688]

It looks fantastic. I'd love to give it a try some time.

[@MetroAndroid]

I feel like it's important to mention that infrared wouldn't necessarily "look white," and the white vs dark is just a way of visualizing the contrast between high and low infrared in a way that humans can actually observe. So trees wouldn't look like winter in infrared but probably more like a bright bloody redder than red color that doesn't exist in visible light.

[@eduardog3000]

"but probably more like a bright bloody redder than red color that doesn't exist in visible light" And that's only if we were seeing in *only* infrared. I'd imagine if we just extended our visible range into infrared, we'd still be seeing more green than infrared coming off the trees.

[@Shonade_Malik]

@@eduardog3000 Since your visible range is extended, your brain forces to make a new color. It could be an entirely new color, or just a deep red. And yes, probably we'd be seeing green, but in other places where there's lots of infrared emission, they would look like an unusual red.

[@DrAndrewSteele]

True, it probably wouldn’t look white-but what colour exactly it would appear is hard to say. Wavelengths of light are a physical phenomenon but colours are all in the mind!

[@DrAndrewSteele]

@@eduardog3000 Actually, plants usually reflect a lot more IR than green! www.researchgate.net/figure/Characteristic-plant-reflectance-spectrum-with-absorption-features-of-example-compounds_fig1_326110050

[@joeysipos]

It’s hard to say what near infrared light looks like because it’s below the Red wave length… so it ain’t red anymore lol. Who knows what it really looks like…

[@Scudmaster11]

Alot of infrared videos are only thermal infrared not infrared light... this is the type of videos they should be

[@MedlifeCrisis]

And to think I ended up here due to a tweet about toxic megacolon

[@davidamadore]

Now do exactly the same in the (near) ultraviolet, please!

[@DrAndrewSteele]

It’s on the to-do list :)

[@davidamadore]

Great! One even wilder idea (but I don't know how easy it would be to find the hardware) would be to film simultaneously in near-IR, visible and near-UV, and render this as red, green and blue channels to form a kind of "extended visible" false image color. I'm particularly interested in what the skin color of various ethnic types would look like in this model. (Of course, the difficulty would be to decide how to relatively calibrate the three channels. Perhaps use a blackbody spectrum at 6500K as reference "white".) Also, the slightly further infrared (shortwave IR, around 1.5µm) seems interesting as well. In contrast to near IR, human skin is apparently always dark in that region.

[@DrAndrewSteele]

Ha, yes, it would be technically challenging! You’d need a beamsplitter if you wanted to overlay them…we used two side-by-side cameras but parallax means that they don’t quite line up. I have played around with this a bit in the past, but only in still photos where you can take several shots and overlay them later… See 500px.com/andrewsteele/galleries/multispectral for a few examples! I’d love a 1.5µm SWIR camera…sadly slightly out of our budget for the moment!

[@davidamadore]

Great multispectral images! Even if it's just stills, it's fascinating. I'd love it if you could take one of a group of people with various skin tones so we could compare the ordinary visible (red+green+blue) image and the composed IR+green+UV image. (Of course, if you have to get everyone to stay perfectly still, I can imagine how challenging that would be.)

[@Redpy5]

Veritasium recently released a UV video at kzbin.info/www/bejne/jGquZ5qgh5VqhtE . I was actually brought here by +Lab, Camera, Action! comment on said video. Was really glad to see it, as I was obsessed with IR photography as a teen and even made some diy IR goggles thanks to the user KipKay here on KZbin (kzbin.info/www/bejne/fmOQn4NordFskMk).

[@ElectricalSwift]

This is an amazingly well made video! Awesome stuff :)

[@DrAndrewSteele]

Thanks!

[@701983]

I'd love to see a whole movie filmed in near infrared! No fake colors, just black-and-white!

[@realemperorkuzco]

Dune part 2?

[@eye4invisible787]

Love the transitions in this video, especially the one beginning at 0:16 as you pan past the tree! :) Which IR filter did you shoot this with? 720nm? Also, how did you rig up the 2 cameras side-by-side?

[@DrAndrewSteele]

Thank you! Yes, it’s a 720 nm IR filter: Hoya R72. The cameras were on a cheap dual camera mount like this: amzn.to/2Xq39hM It was a bit rickety but it did the job!

[@durgeshpradhan6450]

Amazing video! It really took me into a new world! Thanks @Andrew and team

[@Askjerry]

Very entertaining video. Hard to believe your channel is sub 1K subscribers... with videos like this that will change quickly! Subscribed.

[@brianhale3448]

Only thing to make it better would be to show the helicopter footage on a hazy day in visible light vs infrared. As an infrared photographer I know how well IR cuts thru but it wasn't shown here, only mentioned.

[@DrAndrewSteele]

Ha! That would have been ideal… Unfortunately that footage was actually taken handheld through the window of a commercial flight, and I think my arms would have expired if I’d had to support both cameras for the duration. :)

[@brianhale3448]

It's still fantastic and a lot easier to send someone your video than explain "it's not snow" every time without sounding annoyed haha.

[@DrAndrewSteele]

Haha! Glad to have provided a (niche) public service!

[@eye4invisible787]

@@DrAndrewSteele You need a full spectrum converted drone :)

[@DrAndrewSteele]

@@eye4invisible787 Haha, yes please!

[@8randomprettysecret8]

Feels like an otherworldly dream. Outstanding 😮

[@Makatea]

There are also certain garments, made of synthetic fiber, which are IR-transparent. Might make a good followup-video with the potential to go viral, depending on how you aproach it ;-)

[@LeylaKazim]

good work dude - loved it! 👏😊

[@peterlightowler]

Do you know if there is a particular IR wavelength, such as 590nm that can see through tinted windows?

[@j.m9177]

heard you on talk radio with katherine boyle last night (8-9/2/19). sounded too intriguing not to have a gander. glad i did. cheers.

[@PPYTAO]

Amazing video 👌

[@anttiv7109]

Why is this black & white even though I see IR photos often being different shades of red?

[@DrAndrewSteele]

Those reddish ones are probably unprocessed! Of the RGB sensors in cameras, the red is by far the most sensitive to infrared, so pictures look red unless you alter them in post. In this case I enhanced the IR effect a bit by mainly using the G and B channels, which are only sensitive to longer IR wavelengths!

[@itsanumolu]

What camera are you guys using to record in infrared?

[@DrAndrewSteele]

It's a converted DSLR with the IR blocking filter removed and replaced with some fused silica, which lets through everything from UV to IR. Then we used an external IR filter to block visible and UV. :)

[@RD5500]

@@DrAndrewSteele How do you transition from colour to ir so seamlessly?

[@DrAndrewSteele]

@@RD5500 Those scenes were filmed with two cameras side by side, one visible, one IR!

[@RD5500]

@@DrAndrewSteele Oh, i see. Its really well put together that i didnt quite notice the slight difference of perspective. I thought you used some special filter or something. Nice vid, man. Also you're really quick to reply lol...

[@DrAndrewSteele]

@@RD5500 That glitch transition covers a lot. ;) And thanks dude!

[@majortom4543]

I want one of those cameras. The footage looks cool

[@MemesnShet]

Looks like a weird dream scene from an old movie where everyone wears white polos lol

[@claridadespontanea1195]

Wonderful!

[@kjy05]

Interesting❤

[@Axgawd]

Brilliant

[@Mysoi123]

I love visible light!

[@brotherandy]

What would things look like in just red, or just blue, etc?

[@DrAndrewSteele]

You can actually try this yourself with photo editing software. A colour photo is made of red, green and blue channels, so you can separate them out and see!

[@kallelnavarre6507]

I love inferred so cool 😎

[@sandwich2473]

You could get some really interesting and moody shots if you colour burned a full spectrum video of the underground onto the infrared video and did some colour correction

[@DrAndrewSteele]

Haha that would be cool! I’ve done it a few times before for landscapes, which makes for some very strange colours (very light green trees, and the whole background goes blue because the blue light is scattered but still pretty detailed because the IR cuts through the haze…)

[@ib03y7]

is this an infrared camera or infrared filter? if so which filter please!

[@pathduck]

Very cool. Wondering about the sunglasses - some are completely clear, I assume those are polarized while the ones that are still dark will be non-polarized?

[@DrAndrewSteele]

Great question, and I’m not totally sure of the answer! It’s probably just ‘different dyes have different responses to the infrared’, which is a bit vague. :) I don’t think it’s likely to be polarisation though-most polarising filters don’t affect IR! In fact, it’s a common trick if you don’t have an IR filter to use two crossed polarisers instead, which will block all the visible light, but let the IR pass through unaffected. If anyone has any ideas do let us know!

[@pathduck]

Yeah, I just thought it was the cheap ones that were totally transparent. Did some searching, appears some sunglasses block IR light (partially or fully) - but not so sure about the actual benefit, since IR is not as damaging to the retina like UV light is. diglloyd.com/articles/Recommended/sunglasses.html Looks serious enough, even if obv. pushing a brand of glasses.

[@DrAndrewSteele]

Cool, that’s really interesting! Might partly be a glass/plastic thing. And agreed it’s less damaging than UV, but now I’m wondering what the effects are…

[@adityaabdilahyusuf6197]

Awesome video

[@aarijzafeer]

Are there infrared cameras available on sale

[@DrAndrewSteele]

Yes, you can buy modified cameras or have an existing camera modified for IR. The cheapest way might just be to buy an IR filter like a Hoya R72 amzn.to/2sZDujf and try it on an existing camera you have though…a lot of cameras leak a bit of IR and you can take pictures in the infrared without modifying. :)

[@prevarikator]

Dune 2024 brought me here!

[@DrAndrewSteele]

Great to see infrared hitting the mainstream!

[@KevinKurzsartdisplay]

I would be curious to know what things look in mid and far infrared light.

[@DrAndrewSteele]

Me too! One day…mid- and far-infrared cameras are EXPENSIVE (but definitely on the to-make-a-video list!).

[@olmocuaron]

Being a londoner, colorless infrared London looks more colorful than actual London

[@MrVasher]

The thermal range is wider for perception than the color one! In the thermal range, we could see through things, better than X-rays! Superman actually had thermal vision, not x-ray vision!

[@InfraredVisuals]

Interesting.

[@joeysipos]

This is confusing because what we are looking at here is not Infrared but Near Infrared… Infrared would be looking at heat signature below the visible light spectrum…

[@701983]

Near infrared doesn't mean "visible light nearby infrared" (which would be red light), but "invisible infrared radiation near the visible spectrum", wavelenghts of ~1 µm. "Low" temperature (e.g. 20°C) heat radiation (thermal imaging) is mid-wavelength IR, about 10 µm.

[@Cyruscosmo]

Steve Mould sent me ;-)

[@doctorpex6862]

2:45 that is how Jesus turns water into wine

[@treyusher32]

The way at 2:26 you can see that guy's veins through his arm is insane

[@amantin]

Woe..!!!!

[@MrJoshameeGibbsVideo]

What camera did you use?

[@DrAndrewSteele]

It was filmed with a Nikon D5200, converted to full-spectrum :)

[@Addsomehappy]

Spooky.

[@AgnideepSarkar90]

which IR camera did you use?

[@DrAndrewSteele]

It’s a Nikon D5200 which I got converted to full-spectrum!

[@nekrosis4431]

Why does this have

[@skarrambo1]

Thanks to Steve Mould for bringing me here -l as a Physicist and enthusiast Photographer, this video was wonderful! Just a slight caveat, though I'm sure some Physicists wouldn't take issue with it, I think it's more accurate to say blue light is scattered *more* in the atmosphere than red or green, as opposed to *better*

[@Veptis]

I prefer long wave infrared. I own a few cameras for it, but the cameras aren't of such a great image qaulity

[@DrAndrewSteele]

I am definitely jealously eyeing LWIR cameras… When I get back to making videos that’s definitely something on my list! Enjoyed your making toast vid!

[@Veptis]

@@DrAndrewSteele it took me a long time to get where I am starting to be now on the hardware end. Getting old cores is the cheapest way in and the nice lenses you get is beneficial. Join the EEVblog subforum on thermal imaging if you have any specific questions. The two public videos I uploaded were shot on a QVGA+ core and I am currently trying to swap the lens onto a VGA core for better resolution. I have to see how to manage that, but I might not get to it for a few weeks. There might also be a new video soon that highlights people.

[@DrAndrewSteele]

@@Veptis Cool, looking forward to it! And I was nerding out lurking on the EEVblog forums a few months ago when I went through a phase reading about this. :)

[@rogerrabbit7469]

How are these images different from thermal infrared?

[@DrAndrewSteele]

They're a very different wavelength! These images are around 800 nm, which is pretty close to the 400-700 nm of visible light. Thermal infrared is more like 8000+ nm.

[@rogerrabbit7469]

@@DrAndrewSteele ok thanks for replying..but just out of curiosity would you be able to see the light beam of a ceramic infrared heating light in total darkness using the camera?

[@anttoes32]

Why are most of the clothes white?

[@DrAndrewSteele]

Great question, and I’m not 100% sure but I think it’s because most undyed fabrics are white (because structures in the fabric are on the same scale as light wavelengths so they scatter them-see Steve Mould’s great video on why white things are white! kzbin.info/www/bejne/nabKZ2qcZsRroK8 ), and most dyes aren’t designed to have any effect in IR, so you’re left with high levels of reflection/scattering…

[@chuckygobyebye]

If you like that, check out Red Eye Reeves.

[@zachsurp]

wayyyyyy too dramatic with that music and VO but i did like the portraits

[@doxxius3536]

Once again we can thank Susan Wojcicki for generously NOT promoting interesting channels on KZbin. KZbin just keep going like that, you're only seven years late….

[@kxriso]

Geidi Prime:

[@PenisGabber]

What's the camera used?

[@DrAndrewSteele]

It’s a Nikon D5200 which has been converted to full-spectrum by removing the internal IR blocking filter and replacing it with a piece of fused silica.

[@PenisGabber]

@@DrAndrewSteele Thank you!

[@patsonzgambo9672]

geidi prime

[@mipe7755]

Please tell me where you shot 3:23

[@DrAndrewSteele]

That’s down by the Serpentine in Hyde Park. :)

[@mipe7755]

Thank you, I love the roof of that building :D And your footage too ;)

[@DrAndrewSteele]

Haha thanks :)

[@pierrecrampagne6826]

Original les vues de Londres, l'infrarouge va mieux aux végétaux, qu'a ds sujets humains, maintenant essayez la couleur ( cageot de citrons, d'oranges, et faites des portraits, des objets en cuivre etc) vous allez être surpris par la couleur des photos.Si dans les couches normales vous avez bleu, vert, rouge, pour l'infrarouge vous avez vert, rouge, et infrarouge. Dans le métro, j'aurais ajouté un flash avec une gélatine rouge foncé et faire des photos avec le flash que personne ne verra, y compris sur des a u t o s k o u t e r le soir ou la nuit tombée en noir et blanc.

[@wizzard211]

Common man! I hate this type of misinformation and confusion. Dude! you have no idea what color it will be when looking in infrared, because you can't imagine a new color. For that exact purpose it was intentionally rendered in white or black (or whatever color we can perceive), which he didn't say , he delivered the informations as IF infrared is white per se. From our point of view when we look through infrared we "see" additional context previously unseen and in order to visualize it clearer we color it, but that's not the color it will be. In fact for every creature in will be a different color because of the way the eyes are constructed.

[@RoodeMenon]

In infrared there is no race.

[@iComplainer]

Do you want *subscribers??* Because this is *how you get* subscribers.

[@jeremy-ws1rb]

Ultraviolet makes people look dark and purple while infrared makes them look white as hell

[@DrAndrewSteele]

It's amazing the difference 400 nanometres can make, isn't it?

[@andreyserebryakov2231]

Boring