Sulaiman
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Chemical colour references
When photographing or videoing chemicals my phone camera (like most) does an attempt at white balancing,
so depending upon lighting, background etc the colours of chemicals or solutions are not 'true'.
A set of 'standard' colours in the background would allow true colour correction or comparison.
So I am looking to make a rainbow of colours that can be used as a reference.
Ideally the colours should be reproducible by anyone anywhere and be long term stable.
So far I have only got blue copper sulphate e.g. 0.5M solution.
Solutions of other coloured chemicals that I am familiar with are subject to oxidation or reduction (e.g. methyl blue, methylene blue, dichromates
etc.)
This must have been done before but a quick Google search failed.
Can you suggest stable chemical solutions of various colours?
CAUTION : Hobby Chemist, not Professional or even Amateur
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pantone159
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Darren L. Williams et. al., 'Beyond lambda-max: Transforming Visible Spectra into 24-bit Color Values'.
Journal of Chemical Education, Vol 84, No 11, Nov 2007, p1873-1877.
A student laboratory experiment to measure the transmission spectra of some common chemical solutions, and determine the rgb values. The experiment
used solutions of 1M CoCl2, 1M NiCl2, 1M CuSO4, and 0.005M KMnO4. That covered red,green,blue,purple. The KMnO4 might not be stable.
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macckone
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Get a pantone color swatch card or set.
Or you can buy select color swatches.
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DraconicAcid
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The amine complexes of copper and nickel will be stable long-term.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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pantone159
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The card macckone mentions might be the MacBeth ColorChecker card. It is a card with 24 different color swatches, specifically designed for
calibration of photos/video. They are not super cheap, I think in the range $50-$100, presumably because they are careful about using the right inks
so the colors are really correct.
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mayko
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I picked up a few of these but never really used them. Recently I've been thinking about the same sort of thing, how to convey & measure
qualitative color:
https://www.adafruit.com/product/1334
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"Chemicals, chemicals... I need chemicals!" - George Hayduke
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unionised
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Any help?
https://en.wikipedia.org/wiki/Pt/Co_scale
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Bedlasky
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Quote: Originally posted by Sulaiman  | | Solutions of other coloured chemicals that I am familiar with are subject to oxidation or reduction (e.g. methyl blue, methylene blue, dichromates
etc.) |
Dichromates/chromates form stable solutions.
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wg48temp9
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| Quote: Originally posted by pantone159 | Darren L. Williams et. al., 'Beyond lambda-max: Transforming Visible Spectra into 24-bit Color Values'.
Journal of Chemical Education, Vol 84, No 11, Nov 2007, p1873-1877. |
Thanks pantone, thats a useful reference on the subject of defining colour.
Attachment: defining-colour-williams2007.pdf (1.7MB)
This file has been downloaded 317 times
and a useful file on white balancing algorithms ? sorry the file will not load, I will try in a new post.
[Edited on 10/7/2020 by wg48temp9]
I am wg48 but not on my usual pc hence the temp handle.
Thank goodness for Fleming and the fungi.
Old codger' lives matters, wear a mask and help save them.
Be aware of demagoguery, keep your frontal lobes fully engaged.
I don't know who invented mRNA vaccines but they should get a fancy medal and I hope they made a shed load of money from it.
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wg48temp9
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and a useful file on white balancing algorithms
Attachment: AutomaticWhiteBalanceAlgorithmsforDigitalStillCameras-aComparativeStudy.pdf (3.8MB)
This file has been downloaded 312 times
I am wg48 but not on my usual pc hence the temp handle.
Thank goodness for Fleming and the fungi.
Old codger' lives matters, wear a mask and help save them.
Be aware of demagoguery, keep your frontal lobes fully engaged.
I don't know who invented mRNA vaccines but they should get a fancy medal and I hope they made a shed load of money from it.
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sciece nerd
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Ferric nitrate or chloride should also work for yellow.
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Sulaiman
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I have some iron (II) and iron(III) solutions in partially sealed containers to check stability
https://www.sciencemadness.org/whisper/viewthread.php?tid=15...
Pre-printed pantone charts are expensive, so is cobalt chloride, so not cheap for hobbyist references.
CAUTION : Hobby Chemist, not Professional or even Amateur
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