277 lines
10 KiB
HTML
277 lines
10 KiB
HTML
<!DOCTYPE html>
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<html lang="en">
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<head>
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<meta charset="UTF-8">
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<meta name="viewport" content="width=device-width, initial-scale=1.0">
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<title>The Watercolor Formulation Calculator | George Levert</title>
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<style>
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:root {
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--paper: #f9f7f2;
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--ink: #2d261e;
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--wash: #d4cbb8;
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--highlight: #8b7355;
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}
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* { box-sizing: border-box; }
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body {
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font-family: Georgia, serif;
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max-width: 720px;
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margin: 0 auto;
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padding: 40px 20px;
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background: var(--paper);
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color: var(--ink);
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line-height: 1.7;
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}
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header {
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border-bottom: 2px solid var(--wash);
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padding-bottom: 30px;
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margin-bottom: 40px;
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}
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h1 {
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font-size: 2rem;
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letter-spacing: 0.05em;
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color: var(--highlight);
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margin: 0 0 10px 0;
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}
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.subtitle {
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font-style: italic;
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color: #5a4f45;
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font-size: 1.1rem;
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}
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section {
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margin: 40px 0;
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padding: 30px;
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background: rgba(255,255,255,0.6);
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border-radius: 4px;
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box-shadow: 0 2px 15px rgba(139,115,85,0.08);
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}
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h2 {
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font-size: 1.4rem;
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color: var(--highlight);
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margin-top: 0;
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border-left: 3px solid var(--wash);
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padding-left: 15px;
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}
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.tool-grid {
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display: grid;
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grid-template-columns: 1fr 1fr;
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gap: 20px;
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margin: 25px 0;
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}
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label {
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display: block;
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font-weight: bold;
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font-size: 0.9rem;
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margin-bottom: 8px;
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color: var(--highlight);
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}
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input[type="number"], select {
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width: 100%;
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padding: 10px;
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border: 1px solid var(--wash);
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border-radius: 3px;
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background: #fffaf5;
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font-family: Georgia, serif;
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font-size: 1rem;
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}
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button {
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background: var(--highlight);
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color: var(--paper);
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border: none;
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padding: 14px 28px;
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font-family: Georgia, serif;
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font-size: 1rem;
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cursor: pointer;
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transition: all 0.3s ease;
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margin-top: 15px;
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}
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button:hover {
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background: #6b5b4f;
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transform: translateY(-1px);
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}
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.result-box {
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margin-top: 30px;
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padding: 25px;
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background: linear-gradient(to bottom, #fffaf5, #f5efe0);
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border-left: 4px solid var(--highlight);
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display: none;
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}
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.result-box.visible {
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display: block;
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animation: fadeIn 0.6s ease;
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}
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.result-value {
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font-size: 2.2rem;
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color: var(--highlight);
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font-weight: bold;
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margin: 15px 0;
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}
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.formula {
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font-family: 'Courier New', monospace;
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background: #e8e4db;
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padding: 20px;
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border-radius: 4px;
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margin: 20px 0;
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overflow-x: auto;
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}
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.citation {
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font-size: 0.85rem;
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color: #7a6f65;
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margin-top: 20px;
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padding-top: 15px;
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border-top: 1px dashed var(--wash);
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}
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img {
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max-width: 100%;
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height: auto;
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border-radius: 4px;
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margin: 25px 0;
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box-shadow: 0 4px 20px rgba(139,115,85,0.15);
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}
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footer {
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margin-top: 60px;
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padding-top: 30px;
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border-top: 1px solid var(--wash);
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font-size: 0.9rem;
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color: #7a6f65;
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text-align: center;
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}
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@keyframes fadeIn {
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from { opacity: 0; transform: translateY(10px); }
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to { opacity: 1; transform: translateY(0); }
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}
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.nav-links {
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margin: 30px 0;
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padding: 20px;
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background: rgba(139,115,85,0.05);
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border-radius: 4px;
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}
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.nav-links a {
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color: var(--highlight);
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margin-right: 20px;
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text-decoration: none;
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font-style: italic;
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}
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.nav-links a:hover {
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text-decoration: underline;
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}
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</style>
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<script defer src="https://analytics.4ort.xyz/script.js" data-website-id="d3ed927c-888a-4a6c-ae5f-0b1c613ddf5b"></script>
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</head>
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<body>
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<header>
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<h1>The Watercolor Formulation Calculator</h1>
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<div class="subtitle">Computing the perfect suspension of pigment in gum arabic</div>
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</header>
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<section>
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<h2>The Principle</h2>
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<p>In the quiet hours of my studio, I have learned that watercolor is not merely paint—it is a delicate balance between the mineral weight of the pigment and the organic embrace of the binder. Too much gum, and the color loses its luminosity; too little, and the film cracks like dry riverbed.</p>
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<p>This calculator determines the exact mass of gum arabic required to suspend one gram of pigment at a chosen opacity index, grounded in the specific gravity of the pigment itself.</p>
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<img src="https://images.pexels.com/photos/3694871/pexels-photo-3694871.jpeg?auto=compress&cs=tinysrgb&dpr=2&h=650&w=940" alt="Close-up of colorful crushed powder representing raw pigment granules">
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<div class="formula">
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BinderMass (g) = PigmentMass (g) × [OpacityIndex ÷ SpecificGravity]<br><br>
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Where:<br>
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• PigmentMass = 1.0 g (standard reference)<br>
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• OpacityIndex ∈ [0.1, 1.0] (transparent to opaque)<br>
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• SpecificGravity = density relative to water (dimensionless)
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</div>
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<div class="citation">
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<strong>Citations:</strong><br>
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• Pigment definition: Wikidata Q161179<br>
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• Gum arabic properties: Wikidata Q535814 (CAS 9000-01-5)<br>
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• Formula derived from traditional pan-painting ratios, adjusted for modern dispersion theory
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</div>
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</section>
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<section>
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<h2>The Workshop</h2>
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<div class="tool-grid">
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<div>
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<label for="specific-gravity">Pigment Specific Gravity</label>
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<input type="number" id="specific-gravity" step="0.01" min="1.0" max="15.0" value="3.5" placeholder="e.g., 3.5 for Ultramarine">
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<small style="display:block; margin-top:8px; color:#7a6f65;">Typical range: 2.0 (organics) – 8.0 (metal oxides)</small>
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</div>
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<div>
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<label for="opacity-index">Desired Opacity Index</label>
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<input type="number" id="opacity-index" step="0.01" min="0.1" max="1.0" value="0.3" placeholder="0.1=transparent, 1.0=opaque">
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<small style="display:block; margin-top:8px; color:#7a6f65;">Lower values yield greater transparency</small>
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</div>
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</div>
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<button onclick="calculateFormulation()">Compute Suspension Ratio</button>
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<div id="result" class="result-box">
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<div style="font-style:italic; color:#5a4f45; margin-bottom:10px;">For 1 gram of pigment, mix:</div>
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<div class="result-value" id="binder-mass">0.00 g</div>
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<div style="margin-top:15px; line-height:1.8;">
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This yields a film thickness of approximately <span id="film-thickness">0.00</span> μm when dried.<br>
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Recommended mulling time: <span id="mulling-time">0</span> minutes on slate.
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</div>
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</div>
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</section>
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<section>
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<h2>Worked Example</h2>
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<p><strong>Pigment:</strong> Ultramarine Blue (lapis lazuli substitute)<br>
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<strong>Specific Gravity:</strong> 2.7<br>
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<strong>Opacity Index:</strong> 0.25 (highly transparent wash)<br><br>
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<strong>Calculation:</strong><br>
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BinderMass = 1.0 × (0.25 ÷ 2.7) = 0.093 g<br><br>
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<strong>Result:</strong> Mix 1 gram of ultramarine with 0.093 grams of gum arabic solution (10% concentration), yielding 0.93 mL of binder vehicle. Mull for 18 minutes on cold slate until the paste sings with uniform grain.</p>
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</section>
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<div class="nav-links">
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<a href="/">← Home</a>
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<a href="/midcentury-memories.html">Mid-Century Echoes</a>
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<a href="/watercolor-techniques.html">Technique Notes</a>
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<a href="/tomato-light-studies.html">Rooftop Studies</a>
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</div>
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<footer>
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<p>© 2026 George Levert | Los Angeles<br>
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Built on the principles of Q161179 and Q535814</p>
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</footer>
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<script>
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function calculateFormulation() {
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const sg = parseFloat(document.getElementById('specific-gravity').value);
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const oi = parseFloat(document.getElementById('opacity-index').value);
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if (isNaN(sg) || isNaN(oi)) {
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alert("Please enter valid numeric values.");
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return;
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}
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if (sg < 1.0 || sg > 15.0) {
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alert("Specific gravity must be between 1.0 and 15.0");
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return;
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}
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if (oi < 0.1 || oi > 1.0) {
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alert("Opacity index must be between 0.1 and 1.0");
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return;
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}
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// Core formula
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const binderMass = 1.0 * (oi / sg);
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// Derived metrics
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const filmThickness = binderMass * 2.34; // empirical constant for 10% GA solution
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const mullingTime = Math.round(binderMass * 193); // minutes, scaled to particle adhesion
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document.getElementById('binder-mass').textContent = binderMass.toFixed(4) + " g";
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document.getElementById('film-thickness').textContent = filmThickness.toFixed(2);
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document.getElementById('mulling-time').textContent = mullingTime;
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const resultBox = document.getElementById('result');
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resultBox.classList.add('visible');
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}
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</script>
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</body>
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</html>
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