Blood under Red Light

[hooplala]

Asking this in Lit because its for a work of fiction, and also seems too random and stupid even for Apple Talk.

Anyone know what blood would look like under red light light?  I tried googling, but it doesn't seem to be something lots of people are dying to know.  I could find out in... other ways... but this seems most legal.

Anyone already know?  I won't ask how you know, if you don't want me to.

I suspect it would look black, or possibly just sort of blend in, but knowing for certain would help me a lot.  Thanks folks.

[Prelate Diogenes Shandor]

what background is it against? I imagine that would make a difference.

[Cain]

Stage blood apparently looks like chocolate sauce under a red light, so black might not be far off, especially if its venous blood.

[Prelate Diogenes Shandor]

...especially if its venous blood.

Unless this is occurring in space (or possibly in Detroit) the blood will take on oxygen and take on the red of arterial blood immediately upon being spilled

[Cain]

 

Even "de-oxygenated" venous blood still has a good 75% oxygen saturation, and while initial blood contact with the air can almost reach the high saturation that arterial blood has (roughly 99%) this quickly diminishes due to red blood cells dying.  Therefore, after any prolonged exposure to to the air, blood will take on a darker colour, and this process is quicker with venous blood due to the lower overall saturation level.

If you're going to be a pendant, at least be meticulous about it.

[Prelate Diogenes Shandor]

Even "de-oxygenated" venous blood still has a good 75% oxygen saturation, and while initial blood contact with the air can almost reach the high saturation that arterial blood has (roughly 99%) this quickly diminishes due to red blood cells dying.  Therefore, after any prolonged exposure to to the air, blood will take on a darker colour, and this process is quicker with venous blood due to the lower overall saturation level.

If you're going to be a pendant, at least be meticulous about it.

Well at least I did point out that it wouldn't happen in space or places with no oxygen in the air

[Reginald Ret]

Even "de-oxygenated" venous blood still has a good 75% oxygen saturation, and while initial blood contact with the air can almost reach the high saturation that arterial blood has (roughly 99%) this quickly diminishes due to red blood cells dying.  Therefore, after any prolonged exposure to to the air, blood will take on a darker colour, and this process is quicker with venous blood due to the lower overall saturation level.

If you're going to be a pendant, at least be meticulous about it.

Well at least ActuallyI did point out that it wouldn't happen in space or places with no oxygen in the air

Is more pedantish like this.

RE: OP, I have no experience with that, but I would assume black or dark brown.
Some factors that come into play here (some already mentioned):
How fresh is it?
Is it anemic?
Is it human?
Generally speaking though stuff of colour X under colour X light loses that colour.
Slightly more technical: The closer the wavelength spectrum of the lamp to the wavelength-absorption spectrum of blood, the more black it will be.
Slightly more practical: It is your story so just make the lamp exactly the right colour to make blood completely black.
Though I'm not sure if lamps like that can actually be made.

[LMNO]

Wow, I knew all those years of being a wayward youth would pay off!

Under a red light, a pool of blood is black.  If you smear it, it's a dark rusty brown. 

LMNO
-I wanna take you to the goth club, goth club, goth club

[hooplala]

Thanks guys, I knew I could count on you all. Black it is!

[hooplala]

Even "de-oxygenated" venous blood still has a good 75% oxygen saturation, and while initial blood contact with the air can almost reach the high saturation that arterial blood has (roughly 99%) this quickly diminishes due to red blood cells dying.  Therefore, after any prolonged exposure to to the air, blood will take on a darker colour, and this process is quicker with venous blood due to the lower overall saturation level.

If you're going to be a pendant, at least be meticulous about it.

This is gold. I love you Cain.

[Mesozoic Mister Nigel]

You guys remember that stupid dress? Blue and black, or white and gold?

This question is like that. On a purely physical level, blood under red light reflects red light, just as it reflects red light under full-spectrum conditions. On a subjective experience level, you may experience that as a completely holy fuck that is red red level, or you may experience that on an everything is reflecting red and this is a shiny black that is reflecting red level.

Just to make sure I wasn't missing anything I tested this out just now in my basement. Definitely red, but could easily be perceived as black depending on your top-down processes.

[Mesozoic Mister Nigel]

Blood under UV light, on the other hand, looks black black black to the human eye. So club environments could make a huge difference to the visual experience even if there was also long-wave light present.

[LMNO]

Blood under UV light, on the other hand, looks black black black to the human eye. So club environments could make a huge difference to the visual experience even if there was also long-wave light present.

I had forgotten to account for black lights.  Good call, thanks!

[hooplala]

Well, sounds like I don't have any other option than to spill a good amount of blood under red light.

Right?

Right?

[LMNO]