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The Blackest Material

QuantumCrypto writes "Researchers at Rensselaer Polytechnic Institute have created 'the world's first material that reflects virtually no light.' This anti-reflection technology is based on nanomaterial and could lead to the development of more efficient solar cells, brighter LEDs, and 'smarter' light sources. In theory, if a room were to be coated with this material, switching on the lights would only illuminate the items in the room and not the walls, giving a sense of floating free in infinite space."

3 of 299 comments (clear)

  1. Re:tsk by Anonymous Coward · · Score: 3, Informative
  2. Re:Actually... by jdwilso2 · · Score: 4, Informative

    this is a faulty assumption ... I'll leave the "virtually" out to simplify the statements, but here you go ...

    to say something "reflects no light" does not mean it "absorbs all light" ...

    you are leaving out transmission of light. If a material does not reflect light, it either absorbs or transmits all the rest of the light.

    which is actually what this article is talking about ... material clearer than glass but not quite as clear as air.

    this was quite an errant post as it is both a dupe and factually flawed.

  3. Re:Outside by admactanium · · Score: 4, Informative

    I expect a very practical use for this material, if it is not too expensive, will be as a wall coating to replace green screens in filmmaking. It would allow lighting the subjects without worry about any light spill onto the background, and maybe allow better keying for special effects. You would just replace all pixel values that equal zero with your own background data, instead of keying on that narrow-band green which is, after all, still green.
    except that would be color keying much harder because black naturally exists on objects like people and clothes. the reason things are shot again chroma green and blue is because they're not as commonly occurring in the objects that they're trying to photograph and extract. the reason the green and blue are a very specific color is to make keying easier by isolating that color in one channel of rgb. that way it's much easier to determine the differential information. keying against black is practically useless unfortunately. you'd have to go in and rotoscope everything that is black (like hair or eyeglass frames or belt, etc) or a value of black back in to the image. plus, on set they don't worry about light spilling onto the screen because they're usually much more brightly lit than the subject to keep a consistent tone throughout. presumeably, the reason they use blue and green is to allow for photography of subjects that are in the other color range (ie, guy with green shirt on bluescreen, guy with blueshirt on greenscreen). nobody keys against chroma red because obviously everyone's skin would cause them to be semi-transparent.

    if you're talking about the key color spilling into the subject (like in between hair and such) than that's a different issue. that's why when you do a telecine, you'll do what's called a "suppress pass" which desaturated all of the key's color. that way you can comp the original footage minus the key color back into the comp to kill the color spill without having to hand-draw it into each frame.

    i'm sure it could be used for some pretty interesting techniques in photography and film but color keying isn't likely to be one of them.