fusso
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Converting absorbance/transmittance spectrum into digital colour code?
Compounds are coloured due to absorption of different wavelengths.
So I think it will be interesting if there's a way to convert absorbance/transmittance spectrum of a coloured species of a certain concentration (eg
1M) into a corresponding RGB value.
Then I hope there's someone (or >1?) that have a UV-vis spectrometer/scope to measure out absorbance/transmittance spectra for various species
(metal ions & organic substances) and publish onto SM, then the rest of us could calculate the RGB and compile a list of "chemical colours in RGB"
to be published onto SM wiki. Any thoughts?
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j_sum1
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Let's see.
You want to measure the absorbance at a range of wavelengths and output your result as a colour in rgb format.
Why not just take a photo?
There are good reasons for not doing this.
1. Converting your spectrum data to a single rgb value involves a considerable loss of information.
2. The full spectrum lends itself to analysis and comparison that a single pixel doesn't.
Really, what are you actually trying to achieve?
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fusso
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Quote: Originally posted by j_sum1  | Let's see.
You want to measure the absorbance at a range of wavelengths and output your result as a colour in rgb format.
Why not just take a photo?
There are good reasons for not doing this.
1. Converting your spectrum data to a single rgb value involves a considerable loss of information.
2. The full spectrum lends itself to analysis and comparison that a single pixel doesn't.
Really, what are you actually trying to achieve? |
I did think of that but I also think different cameras and lighting would give different rgb values so I think spectrometers would give more
consistent data?
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fusso
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| Quote: Originally posted by j_sum1 | Let's see.
You want to measure the absorbance at a range of wavelengths and output your result as a colour in rgb format.
Why not just take a photo?
There are good reasons for not doing this.
1. Converting your spectrum data to a single rgb value involves a considerable loss of information.
2. The full spectrum lends itself to analysis and comparison that a single pixel doesn't.
Really, what are you actually trying to achieve? |
Also I want to map the ions onto a colour wheel or sth like that, just like cities on a map.
And of course the spectrum could be saved for future analysis.
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phlogiston
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What you ask is possible and this should point you in the direction:
https://en.wikipedia.org/wiki/CIE_1931_color_space
I don't really see yet why your plan would be a particularly useful thing to do. I've used this myself in the past to calculate the perceived color
and saturation from recorded emission spectra of pyrotechnic compositions. The idea was that you could modify the composition, see how the spectrum
changes and then calculate what that looks like approximately to the human eye.
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"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer |
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mayko
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BoingBoing recently featured in its store some devices designed to do this with reflected light:
https://boingboing.net/2017/10/24/dont-paint-a-room-without-...
https://boingboing.net/2018/04/21/the-nix-pro-color-sensor-m...
There's also an Arduino sensor which does this, though I was a little disappointed in the few minutes I've had to play with mine:
https://www.adafruit.com/product/1334
al-khemie is not a terrorist organization
"Chemicals, chemicals... I need chemicals!" - George Hayduke
"Wubbalubba dub-dub!" - Rick Sanchez
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unionised
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It's impossible.
Neodymium glass has only one spectrum, but it has more than one colour.
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