Presentation on theme: "A Colorimetric Analysis Methodology for Philatelic Studies"— Presentation transcript:
1 A Colorimetric Analysis Methodology for Philatelic Studies Prepared for Stampshow 2010David L. Herendeen12 August 2010
2 How Many Colors?1,2 or 3200,010,010200,020,10There are 2!
3 How Many Colors? 1,2 or 3 There are 3! 230,250,090 230,235,90 220,240,085There are 3!
4 How Many Colors?1,2 or 3200,010,010200,020,010There are 2!
5 What Color Are These 1851 Stamps ? Bright Orange BrownRose BrownIntense Orange BrownDull RedDull ClaretPale Orange BrownMoroccoDull RedRose BrownReddish Orange BrownDeep Orange BrownDull ClaretCourtesy National Postal Museum
6 What Color Are These 1851 Stamps ? Bright Orange BrownRose BrownIntense Orange BrownDull RedDull ClaretPale Orange BrownMoroccoDull RedRose BrownReddish Orange BrownDeep Orange BrownDull ClaretCourtesy National Postal Museum
7 Color is not so Easy IS IT ?? Is there Another Way?
8 Talking Points Some background What we planned What we did What we learnedWhat’s next?NPM Support ...A Retrospective
9 Background What is color? What is colorimetry Spectroscopy and the VSC 6000How are colors measured?Commission International de l’Eclairage (CIE)
10 BackgroundCIE Color ModelsMeasureReflectanceorAbsorption of Light
11 What we planned Use the NPM VSC 6000 to perform colorimetric analysis Understand colorimetry in the philatelic contextUnderstand the scientific measurement of color and its relationship to stampsDetermine if scanning can be used as a cost-effective substitute for spectroscopy
12 What we didAnalyzed hundreds of Slovenian postage due stamps ofRecorded results and reduced dataCorrelated spectroscopic results with human color expertDeveloped interpolation model for use with scanners
22 …What we didColor categoriesDeep brownish carmineBrick Red
23 …What we didColor categoriesDeep brownish carmineBrick RedRed
24 Color categories …What we did Deep brownish carmine Brick Red Red
25 Categories are “Fuzzy” …What we didCategories are “Fuzzy”
26 Categories are “Fuzzy” …What we didCategories are “Fuzzy”1.000.840.400.170.14Fuzzy WeightingFunction
27 Theoretical development …What we didTheoretical developmentFormulated a method for defining color categoriesCreated a model for understanding how individual perception can affect philatelic color identificationCorrelated this model to “real” test dataFormed a building block for future philatelic color research
28 3D Interpolation Function …What we didUsing a scannerSpectroscope for Tristimulus Values (X,Y,Z)Calibrate Your Scanner (R,G,B)3D Interpolation FunctionMaps to: (Xu,Yu,Zu)u’,v’Unknown Sample (Ru,Gu,Bu)
29 What we learned How to apply the VSC 6000 for colorimetry Philatelic color is NOT a matching problem, it is about categorizationColorimetry is faster and cheaper than x-ray spectroscopy methodsScanners can be used to identify colors IF preliminary analysis has been performed
30 What’s next? Completing the scanner mapping Documenting and publishing all resultsExtending the methodology to new projects
31 Documenting the work Two papers: …What’s next?Documenting the workTwo papers:Philatelic Shade Discrimination Based on Measured Color (Herendeen, Allen and Lera)Color Research and Applications and/or London PhilatelistUsing a Scanner to Determine Stamp Shades (Herendeen, Allen and Lera)London Philatelist or Collectors Club Philatelist
32 NPM Support Value of NPM scholarship program Leveraging human resourcesIncubator for IAP
33 Acknowledgements Mr. Allen Kane For his vision of extending the services of the NPM to the philatelic worldMr. Thomas Lera, Winton Blount Chair of Research, NPMFor his continual support and assistance with all aspects of this effortMr. James Allen, Senior Fellow, IAPFor his long hours sorting and categorizing Slovenian postage dues