If you played with camera exposure, maybe we would have been able to see a real difference ? Plus you should have made a multi layer paint and sanded it, so no visible edges, like the spectrolum material.
I like the multiple layers and sanding ideas, the camera exposure might help us to see the differences but RUclips color compression and the limits of your phone screen would both affect your ability to see the differences in the whites
A better question would be: why don't all metals look white? Due to the fact that most metals are almost perfect conductors, they are also almost ideal reflecting materials due to how electromagnetic waves work. A rough sheet of metal should then look white, not "metallic".
@@Anankin12 A rough sheet of metal looks gray, this means it is absorbing and reflecting light in equal amounts, I personally never saw white metal ( not without painting) so I think it most be very hard to polish a metal, to the point it becomes both reflective and very diffuse at the same time, it most be because of the way atoms are arranged very tight in metals, is very easy to polish a metal to be a perfect mirror, but very hard to polish paper for example, that is why mirrors are made of a very twin metal sheet.
@@Argoon1981 no, my point was different; according to electrodynamics, the reflectivity of very good conductors is almost 1.if you have a physics or math education, you can find the equations and its solutions in Griffith's Introduction to Electrodynamics, in the chapter about Electromagnetic Waves. Which means that more than 99% of light is reflected; and that's why our mirrors are a very thin layer of (usually) silver under a protective glass. But they don't look white when a non oxidized sheet of metal is rough. And I don't understand why.
At least the 2.0 is fluorescent. That means if you’re outdoors or have some “standard” lamps, the UV light will not reflect as non-visible UV light, but as visible blue light. That means the white can actually look whiter than white if there’s a lot of UV light. Also it becomes a somewhat bluish/cold white.
4:42 No a RGB light doesn't produce the frequency you want, just varies amount of red, green and blue to fool you eyes like it did. But with a strong light source, a prism and a slit, you could produce quite easily all the frequencies separately.
To me the white 2.0 looked brighter under blue light than the spectralon. Ordered some white 2.0 recently and can't wait for it to arrive so I can see this for myself! Thanks for making this video!
Question about the reflectivity of different wavelengths portion: Guessing the bulb is RGB, in which case, aren’t you just testing those 3 wavelengths? Regardless of the color you see, which is just an illusion.
Have u ever tried to open an RGB bulb bcs if u open that bulb u will see that the bulb contains like 10-20 LED beads in series of size about 1.5×1.2mm and each bead consist of very very tiny RGBs array which are not visible to our naked eyes, so the case is all about dominance u know, try to understand like in our smartphone!
@@utkarshagrawal3640 Anyway, the only wavelengths that get emitted are red, green and blue. Just in different ratios. You won't get real yellow light for example.
Im confused did anyone in this comment thread even watch the whole video??? Because he literally explains it right after he finished testing the wavelengths.
@@gabor6259 The real way to get rich is to sell a not so perfect toothpaste, then when people have teeth problems, direct them to your own dentist and sell them various services
Excellent ! You really come up with some amazing ideas to test I am beginning to think that this is one of THE very best YT channels I have ever come across (I am a physics Ph D , then specializing in applied vacuum and cryogenic engineering) What you are doing is also real physics-in-practice- at-home, which would be ideal for science classes at high school. I wonder if there is a way you can promote your channel to school physics teachers, and thus get more patrons (as well as subscribers ! think of all the school kids who would get hooked on physics after watching just a few of your videos !) Two suggestions about the "degrees of white" experiment : 1. Why not try to paint half the Spectralon disc with White 2.0 and then re-do the tests ? 2. Could you do a real wavelength test with a spectrum created by a prism or diffraction grating ?
It would be interesting to see (figuratively speaking) these same tests in the IR spectrum and UV. How does White 2.0 compare to Spretralon in reflecting IR and UV?
these kind of videos make no sense because you can't accurately reproduce the colors on whatever screen you are watching. Would be nice to see it live though
Hey action lab I just love your videos 😍.Can you make a video on world's lightest object carbon aerogel? Also can you try to mix the whitest white and the blackest black to make the greyest grey😂😂.
I don't know how you can come up with such a result lol. The reflectively here is serving as an adverb to the verb reflect meaning it reflects in a reflective manner. In no way is that acting as a noun so your statement is just incorrect. Oddly enough there is nothing grammatically wrong with this sentence and it also makes sense scientifically, it's just in simpler terms for laymen like you. On the other hand, if that was a joke it was super lame.
Reducing camera exposure step by step in the comparision footage might've helped showing us the difference better. Would you please try it out and include it in your next white 2.0 video?
Wondering if the test would be different if the white 2.0 paint was applied to a similar surface. As it wasn’t flat or smooth it seems to shows up lots of inconsistencies in its texture and obviously this will have influenced its reflection of light. You can see this in the many ridges visible in the colour spectrum test. To my eyes the the white 2.0 looked extremely comparable if not the same, sometimes less or even better. Would be interesting to see a smooth roller used on a smooth, but not gloss finished material. Perhaps the results might be different? Or perhaps they will be the same? Thanks for your excellent videos. I enjoy them very much and appreciated the effort you put in. It’s very time consuming to create, film and edit so well done 👍
A problem with viewing both white substances under the coloured light is that our visual system performs the ‘von kries transformation’. Essentially white objects ‘look white’ or can be recognised as white despite there only being a narrow range of wavelengths reflected. The best protocol would be to use a spectroradiometer to measure the reflectance across the visible spectrum to see how they compare.
Now mix the black 2.0 with white 2.0 exactly 50/50, then mix black 3.0 with white 2.0 50/50 and see what one is a darker grey. Not sure how you will get it exactly 50/50 but you are the action lab. You got this
Awesome vid. I am so surprised by two tings. One the white paint looks much whiter than paper and two the paint looks almost as white as the spectralon.
I have few doubts: 1) Will the worlds blackest material gets heated up easily when compared to spectralon? 2) In a thermodynamic scale, does the temperature of the Blacky or Whity material will be affected only on the visible spectrum or the blacky or whity material's temperature depend on the whole spectrum(from radio-gamma rays)
I wish he would've put the Spectralon disc right on top of the white 2.0 paint for us who aren't looking at it in person. It might've helped us be able to see the difference better on our screens, if there is a difference ;-)
If you wanted to quantify how much light they reflect, maybe get a spectroscope and record the spectrum of the light source and of the two materials, then take the difference between the source and the material.
You can make a video about indicators, such as acidity indicators for various pH ranges (Congo Red, Nitrazine Yellow, Methyl Orange etc. etc.) and oxidation-reduction indicators (Sudan Red, Methylene Blue etc.)
i know this sounds stupid but ,every moving thing has some speed ,right? TIME is moving ,can we determine the speed of TIME and tell that it is moving faster than LIGHT . give this a like if u agree with me/interested. forgive me if i am wrong.
But my problem is if the material has fluorescent properties, i.e., if the material takes the energy from the invisible spectrum (e.g. ultraviolet) and spreads it across the visible range, how would you compare? I think that is the case when it comes to white papers almost certainly containing some sort of bleaching agent.
Yes, many papers are fluorescent. Good art papers usually don’t contain brighteners. But then the pulp is always a bit yellowish too. I suppose there are papers that incorporates not-fluorescent white pigment though.
Thanks! Very interesting! An observation: On my UHD monitor I found that when the Spectralon was overlapping the Paint the boundary "disappeared" almost completely. I was hoping you would leave them overlapping for longer as the contrast (or lack of contrast) really showed how close those two "whites" are. If you redo this with say White 3.0 ... can you leave then overlapping? Anyway, here's the place where that briefly occurs to show what I mean at this place in the video: 3:42. Interestingly, on my UHD monitor the illusion was the white paint looked whiter than the spectralon? I think that's because it was a larger surface area that caused the optical distortion on my monitor? Interesting side note: You mentioned that the Black 3.0 painted object absorbs most of the light so there's virtually no visible edges or boarders. Likewise, the leading edge of the spectralon facing the light source completely disappears, too! (3:54).
So if you shined your laser at an angle on the white paint, would it still be able to "reflect" the light and make a blurry bright spot on the wall where the light hit?
Some very cool materials. Just a thought for when you're doing colour comparison.. could you use a halogen, xenon or Mercury lamp for a broad spectrum white emission and use a diffraction grating or prism to select the colour
A constructive question/suggestion. Why are you not measuring the source light with a photometer or a radiometer? I would suggest to measure the source and then the reflection light levels at the same distances and angles on both. This would probably be easier if you printed a puck the same size to paint as the Spectralon to reduce the variables. Also light contamination is avoidable with some focused light or a smaller source to make measuring behind the source easier without the source contamination of the reflection readings. The largest benifit will get rid of the variables in your filming and what the viewers see. Not at all a complaint about the video.
The rough finish of the paint certainly seemed to make a difference compared to the spectralon. The red light seemed very flat but the other colours showed the imperfections in the surface finish. Also I’m looking at this on a screen recorded by your camera, so it is different for me than you, obviously. Interesting though.
What I want to know is: Did it have a specular highlight? If it's supposed to be perfectly diffuse, then it should not possess one. I could not tell if there was a specular highlight looking at the video.
Always fun to watch your videos... For testing, would this work? I thought you were going to use a white light source and compare the spectrum of the light to the reflected light with a slit and diffraction grating. If your white light source covers the spectrum (ideally would be uniform across the spectrum) then you'd see any obvious attenuation when you compare it to the light source and the material, and then to any other material... Also, what about UV or IR?
*this paint claps when the plane lands*
This is excelent.
Ahahah am dead
that took me a while to get
I don't get it..pls help this fool
JIDHIN DHARAN M.P it is because airplanes are white
This isn't whiter than ultimate frisbee though.
Alr, ngl, I'm not white, but ultimate frisbee was the shit in elementary
We practice ultimate frisbee in the Dominican Republic, not really thought of it as a "white" sport. I would think of cricket as a "white" sport.
@@catman8173 Oh wow, I didn't know that. I'm actually dominican. Never been there before tho
Marques Brownlee would like a word
Everyone: Concentrating on the experiment.
.
.
Me: Wow! he grew a mustache.
Lol I was also looking at that😅
If you played with camera exposure, maybe we would have been able to see a real difference ? Plus you should have made a multi layer paint and sanded it, so no visible edges, like the spectrolum material.
I like the multiple layers and sanding ideas, the camera exposure might help us to see the differences but RUclips color compression and the limits of your phone screen would both affect your ability to see the differences in the whites
Eh. Cameras can’t produce the color of white he’s seeing with his eyes .
0:40 Spent half of my childhood learning science and never thought of this white color vs mirror thing. 😯 Cool!
Lol same. The question just never seemed to come up in my head. Although it really makes sense 🤣😅
A better question would be: why don't all metals look white? Due to the fact that most metals are almost perfect conductors, they are also almost ideal reflecting materials due to how electromagnetic waves work. A rough sheet of metal should then look white, not "metallic".
@@Anankin12 You killed obi wan
@@Anankin12 A rough sheet of metal looks gray, this means it is absorbing and reflecting light in equal amounts, I personally never saw white metal ( not without painting) so I think it most be very hard to polish a metal, to the point it becomes both reflective and very diffuse at the same time, it most be because of the way atoms are arranged very tight in metals, is very easy to polish a metal to be a perfect mirror, but very hard to polish paper for example, that is why mirrors are made of a very twin metal sheet.
@@Argoon1981 no, my point was different; according to electrodynamics, the reflectivity of very good conductors is almost 1.if you have a physics or math education, you can find the equations and its solutions in Griffith's Introduction to Electrodynamics, in the chapter about Electromagnetic Waves.
Which means that more than 99% of light is reflected; and that's why our mirrors are a very thin layer of (usually) silver under a protective glass.
But they don't look white when a non oxidized sheet of metal is rough. And I don't understand why.
I feel bad for his daughter, being blinded by her toy unicorn.
Me: uh that ain't so white
My phone: This idiot has the blue light filter on making it look yellowish 😂
Damnit.. glad you wrote this
Same here but It
still looks yellowish
Oh I have my blue cot glasses on
thank you i turned it off now my eyes hurt
Paint be so white it prolly thinks mayonnaise is spicy
My friend's mom really said that once
watch this paint ruclips.net/video/k_iNbGeFRGg/видео.html
LOL
I was really hoping I'd be the first one to think of that joke 😆
As someone that grew up on a mayonaise farm, that is funny.
The white paint reflects so much light, it almost seems to be glowing.
That’s what I said
At least the 2.0 is fluorescent. That means if you’re outdoors or have some “standard” lamps, the UV light will not reflect as non-visible UV light, but as visible blue light. That means the white can actually look whiter than white if there’s a lot of UV light. Also it becomes a somewhat bluish/cold white.
He's the only guy to have done so many experiments about *black* and white
hahaha
no racism
@@gabrieldelatortilla1 ???
Blacked: "Am I a joke to you?"
I'm surprised that I wasn't the result of such experiments
When your leg tans,but not your arm
4:42 No a RGB light doesn't produce the frequency you want, just varies amount of red, green and blue to fool you eyes like it did.
But with a strong light source, a prism and a slit, you could produce quite easily all the frequencies separately.
Thank you! I came here to say this.
Doesn't he have some kind of degree in physics? Hard to believe that he'd make a basic error like this.
To me the white 2.0 looked brighter under blue light than the spectralon.
Ordered some white 2.0 recently and can't wait for it to arrive so I can see this for myself! Thanks for making this video!
TAL : *Shows science.*
Journalists : 'Man becomes racist for 7 minutes straight.'
His name is James.
Question about the reflectivity of different wavelengths portion:
Guessing the bulb is RGB, in which case, aren’t you just testing those 3 wavelengths? Regardless of the color you see, which is just an illusion.
This is exactly what I thought
Have u ever tried to open an RGB bulb bcs if u open that bulb u will see that the bulb contains like 10-20 LED beads in series of size about 1.5×1.2mm and each bead consist of very very tiny RGBs array which are not visible to our naked eyes, so the case is all about dominance u know, try to understand like in our smartphone!
@@utkarshagrawal3640 Anyway, the only wavelengths that get emitted are red, green and blue. Just in different ratios. You won't get real yellow light for example.
Im confused did anyone in this comment thread even watch the whole video??? Because he literally explains it right after he finished testing the wavelengths.
@@adamaoun1535 And you comment whyle watching.
The Action Lab guy: let's get spectralon in the party..
Me: wait, let me decrease the brightness...
😂😂
His name is James.
@@darciek7175 ok..
Imagine you brush your teeth with that paint, you'll get banned from your local dentist.
Someone should make a toothpaste out of it. This is how to get rich.
@@gabor6259 The real way to get rich is to sell a not so perfect toothpaste, then when people have teeth problems, direct them to your own dentist and sell them various services
That paint is so white it drinks Pumpkin Spice Latte's
watch this paint ruclips.net/video/k_iNbGeFRGg/видео.html
@@anusrivastava6848 lol
It hurts my eyes when you lift up the unicorn covered with white 2.0, it feels like i was looking into the sun
It's not whiter than a Word empty document though.
@@gamesanime268 more like my assignments due two hours from now
@@safin8760 More like some overdue assignments too.
If he was outside you would be literally looking at the total (visible) sun light, contrary to popular belief the sun is not yellow, is blindly white.
awesome and she will love her white unicorn!
Excellent ! You really come up with some amazing ideas to test
I am beginning to think that this is one of THE very best YT channels I have ever come across
(I am a physics Ph D , then specializing in applied vacuum and cryogenic engineering)
What you are doing is also real physics-in-practice- at-home, which would be ideal for science classes at high school. I wonder if there is a way you can promote your channel to school physics teachers, and thus get more patrons (as well as subscribers ! think of all the school kids who would get hooked on physics after watching just a few of your videos !)
Two suggestions about the "degrees of white" experiment :
1. Why not try to paint half the Spectralon disc with White 2.0 and then re-do the tests ?
2. Could you do a real wavelength test with a spectrum created by a prism or diffraction grating ?
It would be interesting to see (figuratively speaking) these same tests in the IR spectrum and UV. How does White 2.0 compare to Spretralon in reflecting IR and UV?
these kind of videos make no sense because you can't accurately reproduce the colors on whatever screen you are watching. Would be nice to see it live though
Maybe.. but at least shows the theory of it, just like reading a book
4:40 i hope you realize that this lamp doesn't go through the visible spectrum?
It's just changing the ratio between red green and blue light.
Bruh i swear some of y'all don't even watch the full video or get temporarily deaf when he literally explains it a minute later
@@adamaoun1535 i stopped watching, since it got boring very quickly
Hey action lab I just love your videos 😍.Can you make a video on world's lightest object carbon aerogel? Also can you try to mix the whitest white and the blackest black to make the greyest grey😂😂.
Truly White and Nerdy! Awesome... Thanks for the vid
0:46 "a mirror reflectively reflects it back"
Hmm
yes
the reflection here is made out of reflection
I don't know how you can come up with such a result lol. The reflectively here is serving as an adverb to the verb reflect meaning it reflects in a reflective manner. In no way is that acting as a noun so your statement is just incorrect. Oddly enough there is nothing grammatically wrong with this sentence and it also makes sense scientifically, it's just in simpler terms for laymen like you.
On the other hand, if that was a joke it was super lame.
@@adamaoun1535 It's like saying that you're "speaking verbally". It sounds redundant.
Reducing camera exposure step by step in the comparision footage might've helped showing us the difference better.
Would you please try it out and include it in your next white 2.0 video?
Wondering if the test would be different if the white 2.0 paint was applied to a similar surface. As it wasn’t flat or smooth it seems to shows up lots of inconsistencies in its texture and obviously this will have influenced its reflection of light. You can see this in the many ridges visible in the colour spectrum test. To my eyes the the white 2.0 looked extremely comparable if not the same, sometimes less or even better. Would be interesting to see a smooth roller used on a smooth, but not gloss finished material. Perhaps the results might be different? Or perhaps they will be the same? Thanks for your excellent videos. I enjoy them very much and appreciated the effort you put in. It’s very time consuming to create, film and edit so well done 👍
That's some great superconductive floating at the beginning!
Nah man my mom’s phone screen at 3AM is still the whitest thing ever exist
You deserve a lot more subscribers and views!
Awesome find. Please do add uses of such materials in various aspects. Also, add cost and how it's actually made. Basically all the attributes!!!
that was cool, but...
is no one gonna talk about his dad moustache?
I gotta paint a room like this!
Him: “here’s the white test white”
White Girls who go to Starbucks: “hold my Frappuccino
lol
U could use a light meter maybe in a dark box, also another great vid !!
1:18, Alright, no need to get personal mate 😂😝
A problem with viewing both white substances under the coloured light is that our visual system performs the ‘von kries transformation’. Essentially white objects ‘look white’ or can be recognised as white despite there only being a narrow range of wavelengths reflected. The best protocol would be to use a spectroradiometer to measure the reflectance across the visible spectrum to see how they compare.
I wonder the difference in temperature between an object painted with White 2.0 and Black 3.0
Quick fact: Frequency is inversely proportional to wavelength.
Big brain
@@PlentyOfTrickShots 😁
It’s almost as if frequency is the amount of wave lengths passing in a certain time period 🤦🏾♂️
Matthias Laroche every day man on the block, smoke trees.
Now mix the black 2.0 with white 2.0 exactly 50/50, then mix black 3.0 with white 2.0 50/50 and see what one is a darker grey. Not sure how you will get it exactly 50/50 but you are the action lab. You got this
Awesome vid. I am so surprised by two tings. One the white paint looks much whiter than paper and two the paint looks almost as white as the spectralon.
another great video showing the nuances of life and vision
Thank you for telling difference between white and mirror...simple but fascinating 😁
the black 3.0 head will never get out of my mind
Love the content. It is impressive how you keep it fresh with the ideas. Your contribution will have a lasting effect on humanity.
The difference I saw with the red is the Spectralon appeared matte to the 2.0 that appeared slightly glossy. Thanks for making such super videos.
You should use a thin glass plate on top of the white paint, in order to smooth the surface :) e.g. these for microscopy
Action lab:- Makes more deeper and deeper tests for comparison
Me:- Shrinks eyes more and more due to eye strain while helping him compare.😂😃😀
Daughter: I want a white unicorn, how white can you make it?
Action lab: *yes*
i really enjoy this guy.
Thank you for all of your excellent videos, you make a difference!
What a good father, getting the whitest paint to paint his daughter’s unicorn.
How does it compare to regular white paint?
I have few doubts: 1) Will the worlds blackest material gets heated up easily when compared to spectralon?
2) In a thermodynamic scale, does the temperature of the Blacky or Whity material will be affected only on the visible spectrum or the blacky or whity material's temperature depend on the whole spectrum(from radio-gamma rays)
Good questions ;)
This man. Gives his daughter a unicorn that she can barely see.
*The paint is so white that it claps when the plane lands*
I wish he would've put the Spectralon disc right on top of the white 2.0 paint for us who aren't looking at it in person. It might've helped us be able to see the difference better on our screens, if there is a difference ;-)
If you wanted to quantify how much light they reflect, maybe get a spectroscope and record the spectrum of the light source and of the two materials, then take the difference between the source and the material.
How much temperature you can by putting vantablack material in Daylight
Shamus: "A New competetor"
the whitest white is youtube on light mode at midnight, i learned the hard way
Can you paint a white sheet to replace the backlight of an LCD display???
So if you mix equal proportion of black 2.0 and white 2.0 will you obtain grey 2.0 ?
You can make a video about indicators, such as acidity indicators for various pH ranges (Congo Red, Nitrazine Yellow, Methyl Orange etc. etc.) and oxidation-reduction indicators (Sudan Red, Methylene Blue etc.)
Sir where do you get to know all thesd experimenta
5:40 ... *Who has summoned the Soviet Empire?*
I searched at chrome for white suddenly your videos notification came.
Is it a coincidence????
in order to see Unicorn, paint them white 2.0.
i know this sounds stupid but ,every moving thing has some speed ,right? TIME is moving ,can we determine the speed of TIME and tell that it is moving faster than LIGHT .
give this a like if u agree with me/interested.
forgive me if i am wrong.
really cool experiment. would be useful to employ a light meter for quantitative results.
It would be interesting if you compared White 2.0 and Spectrolon to paper or some normal white paint using that color-changing lamp.
Electrobooms latest video (presidential beef 5:19 onwards) used the exact technology that you needed
Imagine making a complete half white and complete half black
You should dye your hair with either white 2.0 or black 3.0
Would the worlds whitest white and the worlds blackest black make the worlds greyest grey
How so much material is available to u
But my problem is if the material has fluorescent properties, i.e., if the material takes the energy from the invisible spectrum (e.g. ultraviolet) and spreads it across the visible range, how would you compare? I think that is the case when it comes to white papers almost certainly containing some sort of bleaching agent.
Yes, many papers are fluorescent. Good art papers usually don’t contain brighteners. But then the pulp is always a bit yellowish too. I suppose there are papers that incorporates not-fluorescent white pigment though.
Excellent working
It's so white it thinks that bell peppers are too gosh darn spicy
Can you take a spectrum of both of them? That would be a better test of their wavelength-dependent reflectivity.
So sweet for your daughter!
Action Lab Rocks, thanks for your videos...................
I think you forget 1 experiment: use laser to heat up these white, the more "white" the less heat up.
Perfect for heat of sun
Here's an Idea- paint patterns like I spiral or a chess board with the white 2.0 and the black 3.0 and the shine the 35000 lumen torch onto it :)
It would be so interesting to apply it to a glass surface to see if the perfectly flat surface makes somewhat of a mirror in the back of the glass
Transformation to Nikola Tesla is almost complete😂😂
Mix black 2.0 with white 2.0 you get the Ultimate gray
mustache looks nice bro
Sir you are amazing,watched your all videos one after another,it's adactive science :)
Thanks! Very interesting! An observation: On my UHD monitor I found that when the Spectralon was overlapping the Paint the boundary "disappeared" almost completely. I was hoping you would leave them overlapping for longer as the contrast (or lack of contrast) really showed how close those two "whites" are. If you redo this with say White 3.0 ... can you leave then overlapping? Anyway, here's the place where that briefly occurs to show what I mean at this place in the video: 3:42. Interestingly, on my UHD monitor the illusion was the white paint looked whiter than the spectralon? I think that's because it was a larger surface area that caused the optical distortion on my monitor? Interesting side note: You mentioned that the Black 3.0 painted object absorbs most of the light so there's virtually no visible edges or boarders. Likewise, the leading edge of the spectralon facing the light source completely disappears, too! (3:54).
Do you have UHD monitor
@@djdoc06 That's a good point. When I pause my TV the app covers half the screen with the pause, but understand you pointing this out.
So if you shined your laser at an angle on the white paint, would it still be able to "reflect" the light and make a blurry bright spot on the wall where the light hit?
Some very cool materials.
Just a thought for when you're doing colour comparison.. could you use a halogen, xenon or Mercury lamp for a broad spectrum white emission and use a diffraction grating or prism to select the colour
For the white paint, you should use another method to spread it out. A brush makes small tiny grooves for shadows to reach, losing its ability
A constructive question/suggestion. Why are you not measuring the source light with a photometer or a radiometer? I would suggest to measure the source and then the reflection light levels at the same distances and angles on both. This would probably be easier if you printed a puck the same size to paint as the Spectralon to reduce the variables. Also light contamination is avoidable with some focused light or a smaller source to make measuring behind the source easier without the source contamination of the reflection readings. The largest benifit will get rid of the variables in your filming and what the viewers see. Not at all a complaint about the video.
The rough finish of the paint certainly seemed to make a difference compared to the spectralon. The red light seemed very flat but the other colours showed the imperfections in the surface finish. Also I’m looking at this on a screen recorded by your camera, so it is different for me than you, obviously. Interesting though.
What I want to know is: Did it have a specular highlight? If it's supposed to be perfectly diffuse, then it should not possess one. I could not tell if there was a specular highlight looking at the video.
Always fun to watch your videos... For testing, would this work? I thought you were going to use a white light source and compare the spectrum of the light to the reflected light with a slit and diffraction grating. If your white light source covers the spectrum (ideally would be uniform across the spectrum) then you'd see any obvious attenuation when you compare it to the light source and the material, and then to any other material... Also, what about UV or IR?