Does the human eye have limitations on detecting black surfaces?

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The discussion centers on the limitations of the human eye in detecting black surfaces, particularly polished black surfaces that can reflect light. It is established that while black surfaces absorb most light, they can reflect some light if polished, though they will never be perfectly black. The conversation highlights that the human retina has a threshold for photon detection, meaning that even the darkest surfaces can appear black due to insufficient light reaching the eye. Additionally, the concept of blackness is explored, noting that nothing can be perfectly black except black holes, and that our perception of black is influenced by the absence of light.

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black surfaces apparently absorbs all light, that's why it appears black, but does it ever reflect light off its surface?
what if its a polished black suface..we could actually see our own reflection on these surfaces.. so is there light being reflected at all? is there any difference from the usual reflection?
 
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Something perfectly flat black will reflect no light at all and would essentially be invisible. Such a surface is simply unattainable.

The difference between glossy and flat is that glossy reflects light more or less at the macroscopic angle of incidence. So since no black surface will ever be perfect, they can be polished to reflect like a mirror.
 
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How does a perfectly black surface become 'invisible'. Are you suggesting that it becomes transparent? I thought it would still be black.
 
I think he means that your eyes will receive no light coming from there, which is true. However, as you say, your brain will clearly distinguish that pattern in your retina and label it as "black", which means that you will "see" it.
 
i believe the closest attained [by a special paint] was something like 97 or 98%...pretty damn close, but not quite there yet
 
In a broader sense, nothing is 'black', nor can anything be perfectly black (except for black holes). If an object absorbs light, it will get a little hotter, and so it will emit a little more in the infrared (this is a simplification). If our eyes could 'see' IR, we may find that 'black' objects were actually among the brightest objects!
 
If I recall it properly, the reason why you see "Black" is really because your retinas cannot process (see) a certain color (wavelength) of Violet, at the bottom end of the visible light scale...

Then again, it is a bit like looking up at the night sky (away from cities where you could see those old fashioned things called "Stars") inasmuch as, you think, in your mind, that you see the "inky blackness of outer space", and you have fooled yourself completely! as what you are looking at is chock a block FULL of light, just that, you cannot see light, you only 'see' light when reflecting/interacting off/with a surface...light, when in motion, is completely invisible!

(If you doubt that, just look at/in the space between the lamp and the table...you do not see the light travelling!)
 
Originally posted by Nereid
In a broader sense, nothing is 'black', nor can anything be perfectly black (except for black holes).

Even black holes have Hawking Radiation, but it's effectively black.

Things can look perfectly black to the human eye even if they are not truly black because there is a lower limit for photons hitting the retina for it to register.
 
Welcome to Physics Forums Iron Sun X!

Did you take the solar eclipse photo in your avatar?
Iron Sun X wrote: Things can look perfectly black to the human eye even if they are not truly black because there is a lower limit for photons hitting the retina for it to register.
both an upper and lower frequency limit, and a photons per second limit in either retina (retinal signals are not additive).
 
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