COLORANT KEY

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	<title>COLORANT KEY</title>
	<link>https://colorantkey.cargo.site</link>
	<description>COLORANT KEY</description>
	<pubDate>Thu, 01 May 2025 20:50:23 +0000</pubDate>
	<generator>https://colorantkey.cargo.site</generator>
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		<title>HOME/SPLIT</title>
				
		<link>https://colorantkey.cargo.site/HOME-SPLIT</link>

		<pubDate>Thu, 21 Nov 2024 14:14:07 +0000</pubDate>

		<dc:creator>COLORANT KEY</dc:creator>

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		<description>COLORANT KEY &#38;amp; FIELD GUIDE


&#60;img width="600" height="151" width_o="600" height_o="151" data-src="https://freight.cargo.site/t/original/i/177caf41f99ce58692f6783f8bb412c9b8727b6f9be48f539703ddcc6643db88/Kremer-ZincWhite-LMR.png" data-mid="227724341" border="0"  src="https://freight.cargo.site/w/600/i/177caf41f99ce58692f6783f8bb412c9b8727b6f9be48f539703ddcc6643db88/Kremer-ZincWhite-LMR.png" /&#62;&#38;nbsp; &#38;nbsp;


The Colorant Key &#38;amp; Field Guide comprises a series of
interactive tools designed to support the reading and translation of multiband images. The main feature being the colorant key, which aids in the grouping of colorants based on their
shared, average responses to visible light, ultraviolet radiation, and infrared radiation, as expressed
in multi-band imaging techniques as ultraviolet reflected (UVR 320-400nm),
ultraviolet induced visible fluorescence (UVF 420-680nm), visible (VIS
400-680nm). infrared reflected (IR 830-1100nm [850 peak]), and visible induced infrared luminescence (VIL 830-1100nm).
By employing standardized vocabularies and quantitative metrics such as
scene-referred imaging, CIELAB, and the Munsell color system, the tools provide
reproducible and communicable results across institutions. The key is not
designed to offer definitive colorant identification and does not account for
factors such as binder-pigment interaction, admixtures, or layering. It is a guide intended to support multi-band literacy, and to suggest
actionable next steps following the reading of multi-band images—indicating, for example, whether
further analysis might be warranted with XRF, Raman spectroscopy, or alternate imaging methods. This
directed approach minimizes the trial-and-error phase by narrowing down the
list of potential analyses, thereby saving time and resources. 
The step-by-step nature of dichotomous keys helps in managing cognitive load by
breaking down complex classification tasks into smaller, more manageable parts. Each
step requires the user to retrieve and apply previously learned information,
reinforcing neural connections and promoting a deeper and more organized
understanding of colorant response.


Any information included that has been cited
from other sources is not following the standardized vocabularies or value
references as described in the INFO section.


COLORANT KEY &#38;amp; FIELD GUIDE</description>
		
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	<item>
		<title>INFO</title>
				
		<link>https://colorantkey.cargo.site/INFO-1</link>

		<pubDate>Thu, 01 May 2025 20:50:23 +0000</pubDate>

		<dc:creator>COLORANT KEY</dc:creator>

		<guid isPermaLink="true">https://colorantkey.cargo.site/INFO-1</guid>

		<description>FIELD GUIDE


︎
 COLORANT KEY
To determine dichotomous UVR and IR responses, please refer to the&#38;nbsp; L* value of your sample from the CIELAB color space. &#38;nbsp;

DARK: L* ≤ 80BRIGHT: L* ≥ 81If reference value: X-rite Color Checker Classic square A4: VIS: L*94, IR: L*96, UVR: L*35
&#60;img width="600" height="100" width_o="600" height_o="100" data-src="https://freight.cargo.site/t/original/i/5e0b886777dbb38f7a3b85dd01b689b78faacd4141caa80b2547b176d82efe1d/L-value.jpg" data-mid="231837087" border="0"  src="https://freight.cargo.site/w/600/i/5e0b886777dbb38f7a3b85dd01b689b78faacd4141caa80b2547b176d82efe1d/L-value.jpg" /&#62;


STEP 1. Open your calibrated images in photoshop - UVR &#38;amp; IR. 

* For best results, create a tonal adjustment curve profile for each band and apply to all files using as many Spectralon you have available. VIS, IR, and UVR should all match L* in Spectralon values (+/- 3), here is a visual reference for VIS, IR, UVR:&#60;img width="8688" height="3670" width_o="8688" height_o="3670" data-src="https://freight.cargo.site/t/original/i/9edb0a40a5527b8abb7f194cda0fdd5eed7e39ec9d164f7ae0733d7dce1bab5c/202506-Targets-VIS-Edit.jpg" data-mid="237000579" border="0"  src="https://freight.cargo.site/w/1000/i/9edb0a40a5527b8abb7f194cda0fdd5eed7e39ec9d164f7ae0733d7dce1bab5c/202506-Targets-VIS-Edit.jpg" /&#62;&#60;img width="8688" height="3670" width_o="8688" height_o="3670" data-src="https://freight.cargo.site/t/original/i/e146643a16c2fa2339ee70ec5933ec0b9e346d34fd8a11fcd0f3d9b3397eb389/202506-Targets-IR-Edit.jpg" data-mid="237000577" border="0"  src="https://freight.cargo.site/w/1000/i/e146643a16c2fa2339ee70ec5933ec0b9e346d34fd8a11fcd0f3d9b3397eb389/202506-Targets-IR-Edit.jpg" /&#62;&#60;img width="8688" height="3670" width_o="8688" height_o="3670" data-src="https://freight.cargo.site/t/original/i/920fea5d70cf07a000ea90276b9bdebdfc581f6e01763c06ba57ffee3a99a576/202506-Targets-UVR-Edit.jpg" data-mid="237000578" border="0"  src="https://freight.cargo.site/w/1000/i/920fea5d70cf07a000ea90276b9bdebdfc581f6e01763c06ba57ffee3a99a576/202506-Targets-UVR-Edit.jpg" /&#62;STEP 2. *Optional step* File &#38;gt; Scripts &#38;gt; Load Files into Stack &#38;gt; Add Open Files + Attempt to Automatically Align Source Images.


STEP 3. Select Color Sampler tool, sample size: 31 by 31 average&#60;img width="31" height="24" width_o="31" height_o="24" data-src="https://freight.cargo.site/t/original/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" data-mid="231837102" border="0" data-scale="100" src="https://freight.cargo.site/w/31/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" /&#62; 

STEP 4. Click on the area that you want to sample, you will see the reading pop up. Make sure you change the color reading to LAB by clicking on the eyedropper dropdown arrow in the INFO panel underneath the #1. If you stacked the files, you can now toggle layer visibility to view readings from each layer. You can see in the reading below, that the lightness (L*) value reads 60, which is ≤ 80, meaning the sample is ‘DARK’.

&#60;img width="143" height="64" width_o="143" height_o="64" data-src="https://freight.cargo.site/t/original/i/3f13c887c14e1f5ba2c17a75cd17622fa65dbced351c0634e26b04a243e7f0f9/Screenshot-2025-05-01-at-4.32.52PM.png" data-mid="231837104" border="0"  src="https://freight.cargo.site/w/143/i/3f13c887c14e1f5ba2c17a75cd17622fa65dbced351c0634e26b04a243e7f0f9/Screenshot-2025-05-01-at-4.32.52PM.png" /&#62;

&#38;nbsp;

︎
COLORANT KEY + MUNSELL CALCULATOR
FLUORESCENCE: CHROMA &#38;gt; 20 [If less than 20, UVF: NONE]
If reference value: UV Innovations Target Low, brightest L*= 55 a*=0 b*=0
&#60;img width="600" height="100" width_o="600" height_o="100" data-src="https://freight.cargo.site/t/original/i/2e0a6ef7525e103da5e8d5b5fc0c8f3ea70f0c1e524b46dcf9212af86ec11fbb/UV-value.jpg" data-mid="233556940" border="0"  src="https://freight.cargo.site/w/600/i/2e0a6ef7525e103da5e8d5b5fc0c8f3ea70f0c1e524b46dcf9212af86ec11fbb/UV-value.jpg" /&#62;To determine UVF response, please use the MUNSELL calculator to convert Lab values to Munsell Hue and Chroma.*The system does not provide quantitative fluorescence intensity in physical units (e.g., radiance or lumens). If precise fluorescence intensity measurements are required, consider using spectrophotometers, fluorometers, or imaging systems with calibrated fluorescence intensity scales. These tools can provide absolute values rather than relying on visual assessments.
STEP 1. Open your calibrated image in photoshop - UVF.
** Double check that your reference value (UV Innovations Target) is balanced. Gray values a* b* = 0 or as close as possible on each image.
For more info, see their website for workflow. As many camera RAW programs have a white balance setting that maxes out at 50,000 Temp. You may need to do some color grading to get a properly balanced target OR choose a standard and follow it.STEP 2. Select Color Sampler tool, sample size: 31 by 31 average&#60;img width="31" height="24" width_o="31" height_o="24" data-src="https://freight.cargo.site/t/original/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" data-mid="231837102" border="0" data-scale="100" src="https://freight.cargo.site/w/31/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" /&#62; 

STEP 3. Click on the area that you want to sample, you will see the reading pop up. Make sure you change the color reading to LAB by clicking on the eyedropper dropdown arrow in the INFO panel underneath the #1.&#38;nbsp;STEP 4. Enter your LAB values into the Munsell Calculator to convert.
Munsell color notation: HUE,&#38;nbsp; VALUE/CHROMA

UVF HUE: R, YR, Y, GY, G, BG, B, PB, P, and RP[Hue has been divided into the 10 Munsell hue sectors, Red, Yellow-Red etc.]
&#60;img width="1024" height="1024" width_o="1024" height_o="1024" data-src="https://freight.cargo.site/t/original/i/3c96edd1bc896812aeaf5a704d2eec9aae2ef9cf27959518828947f5a73b6331/MunsellColorWheel-copy.png" data-mid="231837088" border="0" data-scale="53" src="https://freight.cargo.site/w/1000/i/3c96edd1bc896812aeaf5a704d2eec9aae2ef9cf27959518828947f5a73b6331/MunsellColorWheel-copy.png" /&#62;︎VECTOR CHARTTo calculate a response vector graph, please use the VECTOR CHART calculator to chart Lab values measured from each wavelength band. *The calculator only provides discrete, approximate values. For more accurate and continuous values, please use a spectrophotometer.
Vector response chart for Cochineal ︎
&#60;img width="800" height="450" width_o="800" height_o="450" data-src="https://freight.cargo.site/t/original/i/84900d5ea6c517aad711eca0a8598875e0d7605dc3373a00ccc236fd47eb8c90/Reflectance_Chart-4.png" data-mid="231837093" border="0"  src="https://freight.cargo.site/w/800/i/84900d5ea6c517aad711eca0a8598875e0d7605dc3373a00ccc236fd47eb8c90/Reflectance_Chart-4.png" /&#62;STEP 1. Open your calibrated images in photoshop - UVR &#38;amp; VIS &#38;amp; IR. 
** Double check that your reference value (X-rite Color Checker Classic A4: L*=96) on each image.STEP 2. Separate VIS file into the three channels, R + G + B
STEP 3.&#38;nbsp;Optional step* File &#38;gt; Scripts &#38;gt; Load Files into Stack &#38;gt; Add Open Files + Attempt to Automatically Align Source Images.


STEP 4. Select Color Sampler tool, sample size: 31 by 31 average&#60;img width="31" height="24" width_o="31" height_o="24" data-src="https://freight.cargo.site/t/original/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" data-mid="231837102" border="0" data-scale="100" src="https://freight.cargo.site/w/31/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" /&#62; 

STEP 5. Click on the area that you want to sample, you will see the reading pop up. Make sure you change the color reading to LAB by clicking on the eyedropper dropdown arrow in the INFO panel underneath the #1. STEP 6. Enter your L* values into the Vector Chart Calculator to generate chart.
︎Imaging set - up: 
Camera: Modified Canon 5DSR full spectrum conversion. Lens: Coastal Optics Apochromatic lens, 60mm, 1:4.Filters: VIS - IDAS-UIBAR III [400-680nm], UVR - XNite 330C + XNite BP1 [270-400nm], UVF - IDAS-UIBAR III + Wratten 2E [420-680nm], IR - XNite 830 [830-1100nm].Lights: LED bulbs, standard copy set-up using lights designed by the Metropolitan Museum of Art: These 24” linear fixtures were designed to provide consistent uniform illumination for technical cultural heritage imaging. D50 98CRI ISO 3664 compliant visible white channel, 365nm UV, and 950nm IR. The unique compact form-factor incorporates a rotating body to maintain consistent lighting geometry for critical comparative study and multi-band imaging techniques.Targets: x-rite classic mini color checker, UV innovations target [low/medium], labsphere spectralons.Backgound paper: Color-aid Gray 4 (non-fluorescing neutral gray).Questions: lauramargaret.ramsey(at)metmuseum.org*IDAS-UIBAR III no longer available. Comparable options, in order of performance1VIS: MidOpt BP550 [390-740], UVF: MidOpt BP550 + Wratten 2E [420-740]VIS: MidOpt SP700 [400-780], UVF: MidOpt SP700 + Wratten 2E [420-780]VIS: PECA 918 [380-740], UVF: PECA 918 + Wratten 2E [420-740]
 
1. Mastandrea, W.J., K. McFarlin, C. Heins, A. Grant, R. Greenberg, A. Serotta, and D. Kriss. “The 12th International Round Table on Polychromy in Ancient Sculpture and Architecture.” In Letting the Light In: A Comparative Assessment of Visible Bandpass Filters Used in Multiband Imaging of Material Culture. Los Angeles, 2024. &#60;img width="2800" height="1800" width_o="2800" height_o="1800" data-src="https://freight.cargo.site/t/original/i/086a85381a239cad8d6dfb4ca99fb1e4886750bab0c6e3462b9359c2e2600ec8/MET-MBI-Setup-2025.jpg" data-mid="239117779" border="0"  src="https://freight.cargo.site/w/1000/i/086a85381a239cad8d6dfb4ca99fb1e4886750bab0c6e3462b9359c2e2600ec8/MET-MBI-Setup-2025.jpg" /&#62;
︎
Colorants included as references: Kremer Pigment Register, 2002︎
Additional References:
 

Cosentino, Antonino. “Identification of Pigments by Multispectral Imaging; a Flowchart Method.” Heritage Science 2, no. 1 (March 17, 2014). https://doi.org/10.1186/2050-7445-2-8.Dyer, J., Verri, G., &#38;amp; Cupitt, J. Multispectral Imaging in Reflectance and Photoinduced Luminescence modes: A User Manual, 2013. Retrieved from
https://www.britishmuseum.org/pdf/charisma-multispectral-imaging-manual-2013.pdf
Fiske, Betty, and Linda Stiber Morenus. “The Book &#38;amp; Paper Group Annual, v. 23 (2004)” 23 (2004): 21–32.Gettens, Rutherford J., and George L. Stout. Painting materials: A short encyclopaedia. New York: Dover Publications, 2015. 
 

Mastandrea, W.J., K. McFarlin, C. Heins, A. Grant, R. Greenberg, A. Serotta, and D. Kriss. “The 12th International Round Table on Polychromy in Ancient Sculpture and Architecture.” In Letting the Light In: A Comparative Assessment of Visible Bandpass Filters Used in Multiband Imaging of Material Culture. Los Angeles, 2024.
McGlinchey Sexton, J., Messier, P., &#38;amp; Chen, J. J. Development and Testing of a
Fluorescence Standard for Documenting Ultraviolet Induced Visible Fluorescence. In
42nd Annual American Institute for Conservation Meeting (pp. 1–42). San Francisco:
American Institute for Conservation, 2014.
Measday, Danielle, Charlotte Walker , and Briony Pemberton. A Summary of&#38;nbsp; Ultra-Violet Fluorescent Materials&#38;nbsp; Relevant to Conservation , n.d. https://primastoria.wordpress.com/wp-content/uploads/2017/03/uv-relevant-to-conservation.pdf.
Stuart, Barbara. Analytical Techniques in Materials Conservation. Chichester, England: John Wiley &#38;amp; Sons, 2010.
 
 
COLORANT KEY &#38;amp; FIELD GUIDE</description>
		
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		<title>INFO-2</title>
				
		<link>https://colorantkey.cargo.site/INFO-2</link>

		<pubDate>Wed, 08 Jan 2025 15:32:34 +0000</pubDate>

		<dc:creator>COLORANT KEY</dc:creator>

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Interactive Dichotomous Key

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INFO

︎ 
To determine dichotomous UVR and IR responses, please refer to the&#38;nbsp; L* value of your sample from the CIELAB color space. &#38;nbsp;

DARK: L* ≤ 80BRIGHT: L* ≥ 81If reference value: X-rite Color Checker Classic A4: L*=96
&#60;img width="600" height="100" width_o="600" height_o="100" data-src="https://freight.cargo.site/t/original/i/5e0b886777dbb38f7a3b85dd01b689b78faacd4141caa80b2547b176d82efe1d/L-value.jpg" data-mid="228550737" border="0"  src="https://freight.cargo.site/w/600/i/5e0b886777dbb38f7a3b85dd01b689b78faacd4141caa80b2547b176d82efe1d/L-value.jpg" /&#62;

STEP 1. Open your calibrated image set in photoshop - UVR, VIS, IR. 

STEP 2. *Optional step* File &#38;gt; Scripts &#38;gt; Load Files into Stack &#38;gt; Add Open Files + Attempt to Automatically Align Source Images.


STEP 3. &#60;img width="31" height="24" width_o="31" height_o="24" data-src="https://freight.cargo.site/t/original/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" data-mid="231836605" border="0" data-scale="100" src="https://freight.cargo.site/w/31/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" /&#62;&#38;nbsp;Select Color Sampler tool, sample size: 31 by 31 average

STEP 4. Click on the area that you want to sample, you will see the reading pop up. Make sure you change the color reading to LAB by clicking on the eyedropper dropdown arrow in the INFO panel underneath the #1. If you stacked the files, you can now toggle layer visibility to view readings from each layer. You can see in the reading below, that the lightness (L*) value reads 60, which is&#38;nbsp;≤ 80, meaning the sample is ‘DARK’.
** Double check that your reference value (X-rite Color Checker Classic A4: L*=96) on each image.
In

&#60;img width="143" height="64" width_o="143" height_o="64" data-src="https://freight.cargo.site/t/original/i/3f13c887c14e1f5ba2c17a75cd17622fa65dbced351c0634e26b04a243e7f0f9/Screenshot-2025-05-01-at-4.32.52PM.png" data-mid="231836622" border="0"  src="https://freight.cargo.site/w/143/i/3f13c887c14e1f5ba2c17a75cd17622fa65dbced351c0634e26b04a243e7f0f9/Screenshot-2025-05-01-at-4.32.52PM.png" /&#62;
S

   ︎To determine UVF response, please use the MUNSELL calculator to convert Lab values to Munsell Hue and Chroma.
*The system does not provide quantitative fluorescence intensity in physical units (e.g., radiance or lumens). If precise fluorescence intensity measurements are required, consider using spectrophotometers, fluorometers, or imaging systems with calibrated fluorescence intensity scales. These tools can provide absolute values rather than relying on visual assessments.

Munsell color notation: HUE,&#38;nbsp; VALUE/CHROMA
FLUORESCENCE: CHROMA &#38;gt; 20 [If less than 20, UVF: NONE]
UVF HUE: R, YR, Y, GY, G, BG, B, PB, P, and RP[Hue has been divided into the 10 Munsell hue sectors, Red, Yellow-Red etc.]
&#60;img width="1024" height="1024" width_o="1024" height_o="1024" data-src="https://freight.cargo.site/t/original/i/3c96edd1bc896812aeaf5a704d2eec9aae2ef9cf27959518828947f5a73b6331/MunsellColorWheel-copy.png" data-mid="228550738" border="0" data-scale="31" src="https://freight.cargo.site/w/1000/i/3c96edd1bc896812aeaf5a704d2eec9aae2ef9cf27959518828947f5a73b6331/MunsellColorWheel-copy.png" /&#62;&#60;img width="31" height="24" width_o="31" height_o="24" data-src="https://freight.cargo.site/t/original/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" data-mid="231836605" border="0"  src="https://freight.cargo.site/w/31/i/dc6d2747c083b8060757b0de4eb7a97a585c750bc3a36e79a8bcbba41edfc2b7/Screenshot-2025-05-01-at-4.28.58PM.png" /&#62;
︎ To calculate a response vector graph, please use the VECTOR CHART calculator to chart Lab values measured from each wavelength band. *The calculator only provides discrete, approximate values. For more accurate and continuous values, please use a spectrophotometer.
Vector response chart for Cochineal ︎
&#60;img width="800" height="450" width_o="800" height_o="450" data-src="https://freight.cargo.site/t/original/i/84900d5ea6c517aad711eca0a8598875e0d7605dc3373a00ccc236fd47eb8c90/Reflectance_Chart-4.png" data-mid="228550739" border="0"  src="https://freight.cargo.site/w/800/i/84900d5ea6c517aad711eca0a8598875e0d7605dc3373a00ccc236fd47eb8c90/Reflectance_Chart-4.png" /&#62;
︎Imaging set - up: 
Camera: Modified Canon 5DSR infrared conversion.&#38;nbsp;Lens: Coastal Optics Apochromatic lens, 60mm, 1:4.Filters: VIS - IDAS-UIBAR III [400-680nm], UVR - XNite 330C + XNite BP1 [270-400nm], UVF - IDAS-UIBAR III + Wratten 2E [420-680nm], IR - XNite 830 [830-1100nm].Lights: LED bulbs, standard copy set-up using lights designed by the Metropolitan Museum of Art: These 24” linear fixtures were designed to provide consistent uniform illumination for technical cultural heritage imaging. D50 98CRI ISO 3664 compliant visible white channel,&#38;nbsp;365nm UV, and 950nm IR. The unique compact form-factor incorporates a rotating body to maintain consistent lighting geometry for critical comparative study and multi-band imaging techniques.Targets: x-rite classic mini color checker, UV innovations target [low/medium], labsphere spectralon 5% + 99%.Backgound paper: Color-aid Gray 4 (non-fluorescing neutral gray).Questions: lauramargaret.ramsey(at)metmuseum.org*IDAS-UIBAR III no longer available. 
Comparable options, in order of performance1
VIS: MidOpt BP550 [390-740], UVF: MidOpt BP550 + Wratten 2E [420-740]VIS: MidOpt SP700 [400-780], UVF: MidOpt SP700 + Wratten 2E&#38;nbsp;[420-780]VIS: PECA 918 [380-740], UVF: MidOpt SP700 + Wratten 2E [420-740]
 
1.&#38;nbsp;Mastandrea, W.J., K. McFarlin, C. Heins, A. Grant, R. Greenberg, A. Serotta, and D. Kriss. “The 12th International Round Table on Polychromy in Ancient Sculpture and Architecture.” In Letting the Light In: A Comparative Assessment of Visible Bandpass Filters Used in Multiband Imaging of Material Culture. Los Angeles, 2024. 
︎
Colorants included as references: Kremer Pigment Register, 2002
C
C

&#38;nbsp;DRPR-2010_232-20250424-AT-Recto-VIS


Imaging
I


    Start Over


    RESULT
    
    
        Start Over
    
</description>
		
	</item>
		
		
	<item>
		<title>MUNSELL</title>
				
		<link>https://colorantkey.cargo.site/MUNSELL</link>

		<pubDate>Thu, 20 Mar 2025 20:02:32 +0000</pubDate>

		<dc:creator>COLORANT KEY</dc:creator>

		<guid isPermaLink="true">https://colorantkey.cargo.site/MUNSELL</guid>

		<description>CIELAB to Munsell Color Converter
            
This calculator takes your CIELAB values (L, A, and B) and approximates the corresponding Munsell Hue, Value, and Chroma.

            
&#38;nbsp;
  
    
      Consider a small region of interest captured under ultraviolet induced visible fluorescence. Use the color sampler tool with a sample size of 31 by 31 average.
  
 
Enter CIELAB&#38;nbsp; Values


Reflectance Calculator

  body {
    font-family: Arial, sans-serif;
    margin: 20px;
  }
  .hidden {
    display: none;
  }
  .button, .download-btn {
    margin-top: 10px;
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
    background-color: white;
    color: black;
    border: 2px solid black;
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
  }
  .button:hover, .download-btn:hover {
    background-color: white;
    color: grey;
  }
  label {
    display: inline-block;
    width: 260px;
    margin-top: 10px;
  }
  input[type="number"] {
    padding: 5px;
    font-size: 16px;
    width: 80px;
  }
  /* Fixed canvas size */
  canvas {
    margin-top: 20px;
    border: 1px solid #000;
    width: 1000px;
    height: 450px;
  }
  .separator-line {
    border: 0;
    height: 2px;
    background-color: black;
    margin: 20px 0;
  }
  /* External response vector readout */
  #responseVector {
    margin-top: 10px;
    font-size: 16px;
    font-weight: bold;
  }


                L* (Lightness): 
                
            
 A* (Green to Red): 
                
            
 B* (Blue to Yellow): 
                
            
            Calculate


                Hue: 
                Value: 
                Chroma: 
            ︎FLUORESCENCE: CHROMA &#38;gt; 20&#38;nbsp;
[If less than 20, UVF: NONE]
        
    
        // Function to convert CIELAB to approximate Munsell specification
        function convertToMunsell() {
            const L = parseFloat(document.getElementById("L").value);
            const A = parseFloat(document.getElementById("A").value);
            const B = parseFloat(document.getElementById("B").value);

            if (isNaN(L) &#124;&#124; isNaN(A) &#124;&#124; isNaN(B)) {
                alert("Please enter valid values for L, A, and B.");
                return;
            }

            // 1. Calculate Chroma (C*)
            const C = Math.sqrt(A * A + B * B).toFixed(2);

            // 2. Calculate Hue angle (hab)
            let hab = Math.atan2(B, A); // atan2 returns radians between -pi and pi
            if (hab &#60; 0) hab += 2 * Math.PI; // Adjust to range 0 to 2pi
            const habDegrees = (hab * 180 / Math.PI).toFixed(2); // Convert to degrees

            // 3. Determine Munsell hue (letter code)
            let HueLetterCode;
            let HueNumber;

            if (habDegrees &#62;= 0 &#38;&#38; habDegrees &#60; 36) {
                HueLetterCode = 'R'; // Red
                HueNumber = (habDegrees / 36 * 10).toFixed(2); // Scale for 0 to 10
            } else if (habDegrees &#62;= 36 &#38;&#38; habDegrees &#60; 72) {
                HueLetterCode = 'YR'; // Yellow-Red
                HueNumber = ((habDegrees - 36) / 36 * 10).toFixed(2);
            } else if (habDegrees &#62;= 72 &#38;&#38; habDegrees &#60; 108) {
                HueLetterCode = 'Y'; // Yellow
                HueNumber = ((habDegrees - 72) / 36 * 10).toFixed(2);
            } else if (habDegrees &#62;= 108 &#38;&#38; habDegrees &#60; 144) {
                HueLetterCode = 'GY'; // Green-Yellow
                HueNumber = ((habDegrees - 108) / 36 * 10).toFixed(2);
            } else if (habDegrees &#62;= 144 &#38;&#38; habDegrees &#60; 180) {
                HueLetterCode = 'G'; // Green
                HueNumber = ((habDegrees - 144) / 36 * 10).toFixed(2);
            } else if (habDegrees &#62;= 180 &#38;&#38; habDegrees &#60; 216) {
                HueLetterCode = 'BG'; // Blue-Green
                HueNumber = ((habDegrees - 180) / 36 * 10).toFixed(2);
            } else if (habDegrees &#62;= 216 &#38;&#38; habDegrees &#60; 252) {
                HueLetterCode = 'B'; // Blue
                HueNumber = ((habDegrees - 216) / 36 * 10).toFixed(2);
            } else if (habDegrees &#62;= 252 &#38;&#38; habDegrees &#60; 288) {
                HueLetterCode = 'PB'; // Purple-Blue
                HueNumber = ((habDegrees - 252) / 36 * 10).toFixed(2);
            } else if (habDegrees &#62;= 288 &#38;&#38; habDegrees &#60; 324) {
                HueLetterCode = 'P'; // Purple
                HueNumber = ((habDegrees - 288) / 36 * 10).toFixed(2);
            } else {
                HueLetterCode = 'RP'; // Red-Purple
                HueNumber = ((habDegrees - 324) / 36 * 10).toFixed(2);
            }

            // 4. Munsell Value (V)
            const Value = (L / 10).toFixed(2);

            // 5. Display result
            document.getElementById("result").style.display = "block";
            document.getElementById("hue").textContent = `${HueNumber}${HueLetterCode}`;
            document.getElementById("value").textContent = Value;
            document.getElementById("chroma").textContent = C;
        }
    </description>
		
	</item>
		
		
	<item>
		<title>VECTOR CHART</title>
				
		<link>https://colorantkey.cargo.site/VECTOR-CHART</link>

		<pubDate>Tue, 25 Feb 2025 16:49:18 +0000</pubDate>

		<dc:creator>COLORANT KEY</dc:creator>

		<guid isPermaLink="true">https://colorantkey.cargo.site/VECTOR-CHART</guid>

		<description>Response Vector Chart Calculator

  A response vector is a set of numerical values representing the intensity measured in each spectral band.
  
  
      Consider a small region of interest captured by all imaging modalities. Use the color sampler tool with a sample size of 31 by 31 average. Enter L* values for each wavelength band to generate the bar chart. 
    
  
  Reference Line:
  Red dashed line at L* = 80 (Dark/Light Threshold)


Reflectance Calculator

  body {
    font-family: Arial, sans-serif;
    margin: 20px;
  }
  .hidden {
    display: none;
  }
  .button, .download-btn {
    margin-top: 10px;
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
    background-color: white;
    color: black;
    border: 2px solid black;
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
  }
  .button:hover, .download-btn:hover {
    background-color: white;
    color: grey;
  }
  label {
    display: inline-block;
    width: 260px;
    margin-top: 10px;
  }
  input[type="number"] {
    padding: 5px;
    font-size: 16px;
    width: 80px;
  }
  /* Fixed canvas size */
  canvas {
    margin-top: 20px;
    border: 1px solid #000;
    width: 800px;
    height: 450px;
  }
  .separator-line {
    border: 0;
    height: 2px;
    background-color: black;
    margin: 20px 0;
  }
  /* External response vector readout */
  #responseVector {
    margin-top: 10px;
    font-size: 16px;
    font-weight: bold;
  }


  Enter CIELAB L* Values
  
    UVR (320–400 nm) L*:
    
  
    Blue (400–450 nm) L*:
    
  
    Green (500–600 nm) L*:
    
  
    Red (600–700 nm) L*:
    
  
    NIR (830–1100 nm) L*:
    
  
  Calculate
*This method uses perceptual L* data (CIELAB). It calculates reflectance from percieved brightness levels (human vision-based conversion). This method gives mathematically derived reflectance based on simplified perceptual data. It does not involve sensor calibration, which would provide linear sensor behavior.&#38;nbsp;
-------
Multiband imaging isn’t typically calibrated like multispectral and hyperspectral imaging. However, you could in theory calibrate the results to provide a more accurate calculation. This is how:


  Start Over
  Download Chart
  
  
        *To convert L* values to reflectance, the code uses the standard, piecewise equation derived from the CIELAB color space conversion.
        For L* values above 8:
        &#60;img width="240" height="60" width_o="240" height_o="60" data-src="https://freight.cargo.site/t/original/i/4ae490c204d8fec5cd678a4c3deecde8c3a2ca46380cebf70c1ddccc789ce7cf/Screenshot-2025-02-27-at-4.52.06PM.png" data-mid="227366811" border="0"  src="https://freight.cargo.site/w/240/i/4ae490c204d8fec5cd678a4c3deecde8c3a2ca46380cebf70c1ddccc789ce7cf/Screenshot-2025-02-27-at-4.52.06PM.png" /&#62;
        For L* values 8 and below it is linear:
        &#60;img width="185" height="55" width_o="185" height_o="55" data-src="https://freight.cargo.site/t/original/i/ffa4c8fb321ffce080f0920d867cc99625042ac1f952fa4d0ebc7614148d32c7/Screenshot-2025-02-27-at-4.52.15PM.png" data-mid="227366772" border="0"  src="https://freight.cargo.site/w/185/i/ffa4c8fb321ffce080f0920d867cc99625042ac1f952fa4d0ebc7614148d32c7/Screenshot-2025-02-27-at-4.52.15PM.png" /&#62;
      
    
  // Convert CIELAB L* value to relative reflectance (Y/Yn)
  function lightnessToReflectance(L) {
    if (L &#62; 8) {
      return Math.pow((L + 16) / 116, 3);
    } else {
      return L / 903.3;
    }
  }

  // Calculate reflectance data and draw the chart
  function calculateReflectance() {
    // Retrieve user inputs
    var lUV   = parseFloat(document.getElementById('lUV').value);
    var lBlue = parseFloat(document.getElementById('lBlue').value);
    var lGreen = parseFloat(document.getElementById('lGreen').value);
    var lRed  = parseFloat(document.getElementById('lRed').value);
    var lIR   = parseFloat(document.getElementById('lIR').value);

    // Convert L* values to reflectance values
    var rUV   = lightnessToReflectance(lUV);
    var rBlue = lightnessToReflectance(lBlue);
    var rGreen = lightnessToReflectance(lGreen);
    var rRed  = lightnessToReflectance(lRed);
    var rIR   = lightnessToReflectance(lIR);

    // Create wavelengths array from 320 nm to 1100 nm (10 nm steps)
    var wavelengths = [];
    for (var wl = 320; wl = 500 &#38;&#38; wl  600 &#38;&#38; wl  700 &#38;&#38; wl &#60; 780) {
        // Interpolate from Red (at 700 nm) to NIR (at 780 nm)
        return rRed + (rIR - rRed) * ((wl - 700) / 80);
      } else if (wl &#62;= 830) {
        return rIR;
      }
    });

    // Build response vector string
    var responseText = "R = [I_UVR, I_B, I_G, I_R, I_NIR] = [" + lUV + ", " + lBlue + ", " + lGreen + ", " + lRed + ", " + lIR + "]";
    document.getElementById("responseVector").innerHTML = responseText;

    // Hide calculator section and show result section
    document.getElementById('calculator-section').classList.add('hidden');
    document.getElementById('result-section').classList.remove('hidden');

    // Draw the reflectance chart with smoothing
    drawChart(wavelengths, reflectance);
  }

  // Draw chart on the canvas using smoothing with quadratic curves
  function drawChart(wavelengths, reflectance) {
    var canvas = document.getElementById('reflectanceChart');
    var ctx = canvas.getContext('2d');
    ctx.clearRect(0, 0, canvas.width, canvas.height);

    var width = canvas.width;    // 800
    var height = canvas.height;  // 450

    // Chart margins and dimensions
    var padding = 100;  // Increased left padding from 70 to 100
    var topMargin = 60;
    var bottomMargin = 90;
    var rightMargin = 30;
    var chartWidth = width - padding - rightMargin;
    var chartHeight = height - topMargin - bottomMargin;
    var xMin = wavelengths[0];
    var xMax = wavelengths[wavelengths.length - 1];
    var yMin = 0;
    var yMax = 1; // Reflectance values range from 0 to 1

    // Draw axes
    ctx.beginPath();
    // y-axis
    ctx.moveTo(padding, topMargin);
    ctx.lineTo(padding, height - bottomMargin);
    // x-axis
    ctx.lineTo(width - rightMargin, height - bottomMargin);
    ctx.strokeStyle = "black";
    ctx.lineWidth = 2;
    ctx.stroke();

    // Draw x-axis numeric ticks and labels (every 100 nm)
    ctx.font = "12px Arial";
    ctx.fillStyle = "black";
    for (var xTick = xMin; xTick </description>
		
	</item>
		
		
	<item>
		<title>VECTOR CHART CALIBRATED</title>
				
		<link>https://colorantkey.cargo.site/VECTOR-CHART-CALIBRATED</link>

		<pubDate>Thu, 24 Apr 2025 16:39:13 +0000</pubDate>

		<dc:creator>COLORANT KEY</dc:creator>

		<guid isPermaLink="true">https://colorantkey.cargo.site/VECTOR-CHART-CALIBRATED</guid>

		<description>

Calibrated Reflectance Calculator

  body { font-family: Arial, sans-serif; margin: 20px; }
  .hidden { display: none; }
  .button, .download-btn {
    margin-top: 10px;
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
    background-color: white;
    color: black;
    border: 2px solid black;
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
  }
  .button:hover, .download-btn:hover {
    background-color: white;
    color: grey;
  }
  label {
    display: inline-block;
    width: 260px;
    margin-top: 10px;
  }
  input[type="number"] {
    padding: 5px;
    font-size: 16px;
    width: 80px;
  }
  canvas {
    margin-top: 20px;
    border: 1px solid #000;
    width: 800px;
    height: 450px;
  }
  .separator-line {
    border: 0;
    height: 2px;
    background-color: black;
    margin: 20px 0;
  }
  #responseVector {
    margin-top: 10px;
    font-size: 16px;
    font-weight: bold;
  }


Response Vector Chart Calculator - CALIBRATED

  A response vector is a set of numerical values representing the intensity measured in each spectral band.
  
  
      Consider a small region of interest captured by all imaging modalities. Use the color sampler tool with a sample size of 31 by 31 average. Enter the calculated reflectance percentages for each wavelength band to generate the chart. There is some approximation between bands but there will be a visible drop in the chart to emphasize the large gap between the Red and NIR bands.
  
  
  Reference Line:
  Red dashed line at 78.48% (Dark/Light Threshold)


  Enter your calculated reflectance percentages
  
    UVR (320–400 nm) R%:
    
  
    Blue (400–450 nm) R%:
    
  
    Green (500–600 nm) R%:
    
  
    Red (600–700 nm) R%:
    
  
    NIR (830–1100 nm) R%:
    
  
  Calculate


  Start Over
  Download Chart


function calculateReflectance() {
  const UV = parseFloat(document.getElementById('UV').value) / 100;
  const Blue = parseFloat(document.getElementById('Blue').value) / 100;
  const Green = parseFloat(document.getElementById('Green').value) / 100;
  const Red = parseFloat(document.getElementById('Red').value) / 100;
  const IR = parseFloat(document.getElementById('IR').value) / 100;

  const wavelengths = Array.from({length: (1100 - 320) / 10 + 1}, (_, i) =&#62; 320 + i * 10);
  const reflectance = wavelengths.map(wl =&#62; {
    if (wl </description>
		
	</item>
		
		
	<item>
		<title>ΔE* CALCULATOR</title>
				
		<link>https://colorantkey.cargo.site/DE-CALCULATOR</link>

		<pubDate>Thu, 20 Mar 2025 20:27:21 +0000</pubDate>

		<dc:creator>COLORANT KEY</dc:creator>

		<guid isPermaLink="true">https://colorantkey.cargo.site/DE-CALCULATOR</guid>

		<description>

    
        ΔE*
        Delta E measures the difference between two colors in a three-dimensional color space (typically CIE Lab). It quantifies color changes based on three axes: Lightness (L*), Red-Green (a*), and Yellow-Blue (b*). This allows conservators to assess and compare how closely different colorants match, both in terms of the visual result of mixed pigments or as they degrade over time.

        Understanding Color Differences
        ΔL*: Shows how much lighter or darker one color is compared to the other. Positive means the second color is lighter, negative means it's darker.
        Δa*: Positive means the second color is more red than the first. Negative means the second color is more green than the first.
        Δb*: Positive means the second color is more yellow than the first. Negative means the second color is more blue than the first.
        ΔC*: Positive means the second color is more vivid or intense. Negative means the second color is more dull or grayish.
        ΔH*: Measures the difference in hue between two colors, which is a more complex calculation because it involves both the a* and b* components. In practice, ΔH* is always positive, as it represents the magnitude of the angular difference in hue.
        ΔE*: A total measure of how different two colors are, combining all aspects (lightness, chroma, hue, etc.). The higher the value, the more noticeable the difference. A ΔE* of less than 2 is imperceptible to the naked eye.
    
    
  body {
    font-family: Arial, sans-serif;
    margin: 20px;
  }
  .hidden {
    display: none;
  }
  .button, .download-btn {
    margin-top: 10px;
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
    background-color: white;
    color: black;
    border: 2px solid black;
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
  }
  .button:hover, .download-btn:hover {
    background-color: white;
    color: grey;
  }
  label {
    display: inline-block;
    width: 260px;
    margin-top: 10px;
  }
  input[type="number"] {
    padding: 5px;
    font-size: 16px;
    width: 80px;
  }
  /* Fixed canvas size */
  canvas {
    margin-top: 20px;
    border: 1px solid #000;
    width: 1000px;
    height: 450px;
  }
  .separator-line {
    border: 0;
    height: 2px;
    background-color: black;
    margin: 20px 0;
  }
  /* External response vector readout */
  #responseVector {
    margin-top: 10px;
    font-size: 16px;
    font-weight: bold;
  }


        ΔE* Calculator


            Color 1 
            
            
Color 2 
            

Calculate

        
            ΔL* (Lightness difference): 
            Δa* (Red/Green difference): 
            Δb* (Yellow/Blue difference): 
            ΔC* (Chroma difference): 
            ΔH* (Hue difference): 
            ΔE* (Total color difference): 
        
    
    function calculateDeltaE() {
        const l1 = parseFloat(document.getElementById('l1').value);
        const a1 = parseFloat(document.getElementById('a1').value);
        const b1 = parseFloat(document.getElementById('b1').value);

        const l2 = parseFloat(document.getElementById('l2').value);
        const a2 = parseFloat(document.getElementById('a2').value);
        const b2 = parseFloat(document.getElementById('b2').value);

        if (isNaN(l1) &#124;&#124; isNaN(a1) &#124;&#124; isNaN(b1) &#124;&#124; isNaN(l2) &#124;&#124; isNaN(a2) &#124;&#124; isNaN(b2)) {
            alert("Please enter valid numbers for all values.");
            return;
        }

        const deltaL = l2 - l1;
        const deltaA = a2 - a1;
        const deltaB = b2 - b1;

        const C1 = Math.sqrt(a1 * a1 + b1 * b1);
        const C2 = Math.sqrt(a2 * a2 + b2 * b2);
        const deltaC = C2 - C1;

        const deltaH = Math.sqrt(Math.pow(deltaA, 2) + Math.pow(deltaB, 2) - Math.pow(deltaC, 2));

        const deltaE = Math.sqrt(Math.pow(deltaL, 2) + Math.pow(deltaA, 2) + Math.pow(deltaB, 2));

        document.getElementById('deltaL').innerText = deltaL.toFixed(2);
        document.getElementById('deltaA').innerText = deltaA.toFixed(2);
        document.getElementById('deltaB').innerText = deltaB.toFixed(2);
        document.getElementById('deltaC').innerText = deltaC.toFixed(2);
        document.getElementById('deltaH').innerText = deltaH.toFixed(2);
        document.getElementById('deltaEValue').innerText = deltaE.toFixed(2);

        document.getElementById('result').style.display = 'block';
    }
</description>
		
	</item>
		
	</channel>
</rss>