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First ever color X-ray on a human

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Re: First ever color X-ray on a human

#71

Post by ttsda »

8bitsrule wrote: post #66
ekun wrote: post #39

Earlier quoted context omitted.

Which similar to images we see of space where they have altered detectors' responses from different wavelengths of light to be images in the visible spectrum. So we produce beautiful images, but they aren't accurate to what space would look like to the naked eye.

Yep. All those fantastic color pictures of the Orion nebula are just that. (Personally I think there should be a requirement to post, alongside them, true color photos.)

Why? Many times the true colour images aren't even available. How would you represent an infrared or x-ray picture properly, in your view?

False colour images aren't meant to mislead. They're meant to be more useful to understand what you're looking at. "True colour" has no meaning, really.

Re: First ever color X-ray on a human

#72

Post by natezb »

1123581321 wrote: post #65
1996 wrote: post #31

Earlier quoted context omitted.

Doesn't look that much better than a thin slice CT with custom colormaps ("CLUTs"), using a regular greyscale for the high density tissue (bone), and a reduced alpha channel for the low density tissue rendered in yellow. You can get that with a Dicom station and 5 minutes, or for free using Osirix at home and trial/error if you are not used to CTs. Ask for the CD next time you get a scan, or download one of the many…

That may be, but an X-ray is a simpler and cheaper procedure. To achieve “feature parity” with something more expensive is an advance. I’m looking up the things you mentioned and they’re interesting, though. I’d love to see imaging and home-computed assessments become a bigger part of the “quantified self” movement.

What you linked to is a type of CT scan (CT uses X-rays).

Re: First ever color X-ray on a human

#73

Post by tomp »

xamuel wrote: post #68
zwkrt wrote: post #55

Earlier quoted context omitted.

I think the point was that the x-ray 'colors' do not have 1:1 mapping with the colors that our eyes see. So the color is useful to discern different tissues and bones and stuff, but the colors won't look like the colors of those things in real life. We see in a range of wavelengths 0.4--0.7 um. X-rays have no intersection with our visible range. Therefore the best you can do is define some function that maps x-rays i…

Maybe a good way of explaining it would be like this: if someone magically had a blue spine, this technique would still show their spine as being white (unless the doctor already knew their spine was blue and adjusted the parameters accordingly)?

My point is, showing spine as white on X-ray (well, that's probably easy, but generalizing this to other tissues and their "normal"/"expected" color probably isn't) would be tremendously helpful in diagnosis... "peeking inside patients without cutting them up" - and I'm wondering, what's stopping us from doing just that?

Re: First ever color X-ray on a human

#74

Post by wink »

ttsda wrote: post #71
8bitsrule wrote: post #66

Earlier quoted context omitted.

Yep. All those fantastic color pictures of the Orion nebula are just that. (Personally I think there should be a requirement to post, alongside them, true color photos.)

Why? Many times the true colour images aren't even available. How would you represent an infrared or x-ray picture properly, in your view? False colour images aren't meant to mislead. They're meant to be more useful to understand what you're looking at. "True colour" has no meaning, really.

I'd say because without a modicum of knowledge you'd take it for granted. Compare to "images" of dinosaurs where you'll often read "this is what it should look like" vs "we know squat about the color of their skin". And for space pictures, which are 99% touted as "pictures" and not reproductive works, it's even worse. Hell, as I'm writing this I'm tempted to double check what I know about color-correctness of any space photo, and my point was already that I'm in the second stage of not knowing - that there could be something I don't know [0]

[0] https://en.wikipedia.org/wiki/Four_stages_of_competence

Re: First ever color X-ray on a human

#77

Post by StavrosK »

wink wrote: post #74
ttsda wrote: post #71

Earlier quoted context omitted.

Why? Many times the true colour images aren't even available. How would you represent an infrared or x-ray picture properly, in your view? False colour images aren't meant to mislead. They're meant to be more useful to understand what you're looking at. "True colour" has no meaning, really.

I'd say because without a modicum of knowledge you'd take it for granted. Compare to "images" of dinosaurs where you'll often read "this is what it should look like" vs "we know squat about the color of their skin". And for space pictures, which are 99% touted as "pictures" and not reproductive works, it's even worse. Hell, as I'm writing this I'm tempted to double check what I know about color-correctness of any spa…

Why aren't space photos real? For deep space photos, where we have to wait for individual photons, maybe they're false color, but many photos are taken by putting colored filters in front of the lens and then combining the exposures, so they are actually true color.

Re: First ever color X-ray on a human

#78

Post by lurquer »

klipt wrote: post #50
ekun wrote: post #39

Earlier quoted context omitted.

Which similar to images we see of space where they have altered detectors' responses from different wavelengths of light to be images in the visible spectrum. So we produce beautiful images, but they aren't accurate to what space would look like to the naked eye.

Probably more useful than the naked eye in many cases. The colors our eyes can see mostly evolved to detect ripe fruit, not diseased tissue.

Why did fruit evolve to change colors when ripe?

Re: First ever color X-ray on a human

#79

Post by 8bitsrule »

ttsda wrote: post #71
8bitsrule wrote: post #66

Earlier quoted context omitted.

Yep. All those fantastic color pictures of the Orion nebula are just that. (Personally I think there should be a requirement to post, alongside them, true color photos.)

Why? Many times the true colour images aren't even available. How would you represent an infrared or x-ray picture properly, in your view? False colour images aren't meant to mislead. They're meant to be more useful to understand what you're looking at. "True colour" has no meaning, really.

Tell that to the color-blind.

Re: First ever color X-ray on a human

#80

Post by ttsda »

lurquer wrote: post #78
klipt wrote: post #50

Earlier quoted context omitted.

Probably more useful than the naked eye in many cases. The colors our eyes can see mostly evolved to detect ripe fruit, not diseased tissue.

Why did fruit evolve to change colors when ripe?

In many cases so animals would eat them, digest the seeds, and poop them out somewhere else.
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