Vantablack!

[julianm]

http://www.independent.co.uk/news/science/blackest...

I vant some & think it would be perfect for a respray on a Veyron!

[Simpo Two]

"Many people think black is the absence of light. I totally disagree with that. Unless you are looking at a black hole, nobody has actually seen something which has no light," he said.


Perhaps not but it doesn't make the assertion incorrect!

[Asterix]

We often get asked to 'light' the side of a building with the UAE flag and they get upset when we tell them it's not possible to light a certain bit of it.

'Why you not able to light black?!'

[thatdude]

That's incredible. The image of the material on the foil goes some way to illustrating how odd it would be to look at it.

I hope it can be applied quickly to telescope systems and reveal more incredible detail of the deep sky.

[Soov535]

Deeply cool.

[Ive]

Asterix said:

We often get asked to 'light' the side of a building with the UAE flag and they get upset when we tell them it's not possible to light a certain bit of it.

'Why you not able to light black?!'

if you suround the flag with a white large enough frame, the eye will percieve the unilluminated part as rather dark or even black. This is how old cathode ray tube TVs worked. If they are off, the screen is acutally grey. If you now generate a white pattern on the screen the parts of the screen that are not exited wil look black. Your receptive fields in the retina and brain create a contrast enhancement. You judge brithness by comparison with the nearest object of different brightness. the brither the comparision object, the darker the other object will look.

This allows humans and other mammels to have high contrast vision under both rather dark and bright conditions and under high and low contrast conditions.
You can really see this when you try to capture photos under such low contrast consditions. By eye, you see all the details in a dark corner of a room, but on the photo, there is a just a black corner.

Edited by Ive on Tuesday 23 September 15:25

[Asterix]

Understood but most of the buildings here in Dubai are white or a sandy beige colour (if they're not gold reflective glass or something else as ugly) - which they want lit black...

[julianm]

I`ve used a projector connected to one of those `magic` Smartboard whiteboards as used in many UK classrooms. I used to set it to a black background & write on it with pale green. It really did seem to be projecting black - it certainly wasn`t just an absence of light. The blokes who fitted it couldn`t explain it - any ideas?

[s2sol]

There was an item about vantablack on radio 4 this morning at about 7:30. It sounded fascinating. Thanks for posting the link to the picture. It looks astonishing.

[Ive]

julianm said:

I`ve used a projector connected to one of those `magic` Smartboard whiteboards as used in many UK classrooms. I used to set it to a black background & write on it with pale green. It really did seem to be projecting black - it certainly wasn`t just an absence of light. The blokes who fitted it couldn`t explain it - any ideas?

As I wrote above
if you project bright letters on a white board in room that is significantly less bright than your letters the background of the letters will appear dark or even black. the nerve cells in your eye's retina enhance contrast and create that effect. The local structures in the retina are called receptive fields.

http://en.wikipedia.org/wiki/Receptive_field#Visua...


Military use of optical absorbers are usually coating for bolometers. These are the sensors in infrared night vision cameras and sensors.
A bolometers is essentially a tiny insulated thermometer with a superb lack coating on it. Any light that absorbs on it heats the sensor. This is your signal. If you now create an array of those using Silicon microelectronic and mechanical structures, MEMS, you can fabricate imaging sensors.
Such coatings are also sometimes used in laser power meters for either wavelengths that are hard to detect directly, e.g. mid and far infrared, or are at rather high power levels. In theses cases, you use those superbly coating to convert all light energy independent of wavelength into heat energy. This energy will heat up a structure of known thermal properties. From the change in temperature over time you can calculate the incident optical power.

Edited by Ive on Tuesday 23 September 15:30

[Simpo Two]

julianm said:

It really did seem to be projecting black - it certainly wasn`t just an absence of light. The blokes who fitted it couldn`t explain it - any ideas?

If it was projecting black then you must have been using an electric dark bulb...

One point to the Mk1 eyeball.

[julianm]

I ended up with the physics dept trying to explain it with `retinal confusion`- but if you created a shadow thus preventing the `black light` hitting the screen the shadow was certainly less black than the `black` bit being projected. That was in a room with good quality full blackout blinds & the only light coming from the projector. I gave my eyeballs a good talking to but they still couldn`t understand...

[Halmyre]

I bet it's not as black as a priest's socks.

[Asterix]

Or a Spinal Tap album - 'There's something about this that's so black, it's like how much more black could this be? And the answer is none. None more black.'

[IainT]

I guess this was what Hotblack Desiato painted his sun-diver stunt ship with.

[eybic]

They must have found a way to reverse dark suckers.