Calculator White

Calculator White: Advanced White Balance Calculator :root { –primary-color: #004a99; –success-color: #28a745; –background-color: #f8f9fa; –text-color: #333; –border-color: #ddd; –shadow-color: rgba(0, 0, 0, 0.1); } body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: var(–background-color); color: var(–text-color); margin: 0; padding: 0; line-height: 1.6; } .container { max-width: 1000px; margin: 20px auto; padding: 20px; background-color: #fff; box-shadow: 0 4px 8px var(–shadow-color); border-radius: 8px; } h1, h2, h3 { color: var(–primary-color); } h1 { text-align: center; margin-bottom: 20px; } .calculator-section { margin-bottom: 40px; padding: 30px; background-color: #fff; border-radius: 8px; box-shadow: inset 0 2px 4px rgba(0,0,0,0.05); } .loan-calc-container { display: grid; gap: 20px; } .input-group { display: flex; flex-direction: column; gap: 5px; } .input-group label { font-weight: bold; color: var(–primary-color); } .input-group input, .input-group select { padding: 10px; border: 1px solid var(–border-color); border-radius: 4px; font-size: 1rem; width: 100%; box-sizing: border-box; } .input-group input:focus, .input-group select:focus { border-color: var(–primary-color); outline: none; box-shadow: 0 0 0 2px rgba(0, 74, 153, 0.2); } .input-group small { color: #6c757d; font-size: 0.85rem; } .error-message { color: #dc3545; font-size: 0.85rem; margin-top: 5px; display: none; /* Hidden by default */ } .button-group { display: flex; gap: 10px; margin-top: 20px; justify-content: center; flex-wrap: wrap; } button { padding: 12px 20px; border: none; border-radius: 5px; cursor: pointer; font-size: 1rem; font-weight: bold; transition: background-color 0.3s ease; } .btn-primary { background-color: var(–primary-color); color: white; } .btn-primary:hover { background-color: #003366; } .btn-secondary { background-color: #6c757d; color: white; } .btn-secondary:hover { background-color: #5a6268; } .btn-success { background-color: var(–success-color); color: white; } .btn-success:hover { background-color: #218838; } .results-container { margin-top: 30px; padding: 20px; background-color: var(–primary-color); color: white; border-radius: 8px; text-align: center; box-shadow: inset 0 2px 6px rgba(0,0,0,0.2); } .primary-result { font-size: 2.5rem; font-weight: bold; margin-bottom: 10px; } .intermediate-results div, .key-assumptions div { margin-bottom: 8px; font-size: 0.95rem; } .intermediate-results span, .key-assumptions span { font-weight: bold; } .formula-explanation { margin-top: 15px; font-size: 0.9rem; opacity: 0.8; } .chart-container, .table-container { margin-top: 30px; padding: 20px; background-color: #fff; border-radius: 8px; box-shadow: 0 2px 4px var(–shadow-color); } .chart-container canvas { width: 100%; height: auto; } .table-container table { width: 100%; border-collapse: collapse; margin-top: 15px; } .table-container th, .table-container td { border: 1px solid var(–border-color); padding: 10px; text-align: left; } .table-container th { background-color: var(–primary-color); color: white; font-weight: bold; } .table-container td { background-color: #fdfdfd; } .table-caption, .chart-caption { font-weight: bold; color: var(–primary-color); margin-bottom: 10px; text-align: center; display: block; } .article-section { margin-top: 40px; padding: 30px; background-color: #fff; border-radius: 8px; box-shadow: 0 2px 4px var(–shadow-color); } .article-section h2 { margin-bottom: 20px; border-bottom: 2px solid var(–primary-color); padding-bottom: 8px; } .article-section h3 { margin-top: 25px; margin-bottom: 10px; } .article-section p, .article-section ul, .article-section ol { margin-bottom: 15px; } .article-section ul, .article-section ol { padding-left: 25px; } .article-section li { margin-bottom: 8px; } .faq-item { margin-bottom: 15px; padding: 10px; border-left: 3px solid var(–primary-color); background-color: #f1f1f1; border-radius: 4px; } .faq-item strong { color: var(–primary-color); } a { color: var(–primary-color); text-decoration: none; } a:hover { text-decoration: underline; } .internal-links-list { list-style: none; padding: 0; } .internal-links-list li { margin-bottom: 15px; padding-bottom: 10px; border-bottom: 1px dashed var(–border-color); } .internal-links-list li:last-child { border-bottom: none; } .internal-links-list span { display: block; font-size: 0.9rem; color: #6c757d; margin-top: 4px; } /* Responsive adjustments */ @media (max-width: 768px) { .container { margin: 10px; padding: 15px; } .button-group { flex-direction: column; align-items: center; } button { width: 80%; } }

Calculator White: Advanced White Balance Calculator

White Balance Calculator

Accurately determine the correct Kelvin (K) value for your lighting conditions to achieve neutral white in your photographs and videos.

The color temperature of your primary light source (e.g., daylight, tungsten, LED). Typical ranges: 2500K (candle) to 10000K (shade).
The Kelvin value you want your camera to interpret as pure white. 5500K is standard for daylight.
Auto White Balance (AWB) Daylight Cloudy Shade Tungsten Fluorescent Flash Custom (Manual Kelvin) Select your camera's current white balance setting. Choose 'Custom' if you intend to manually set Kelvin.
Enter the specific Kelvin value you want to set manually on your camera.

Results

Intermediate Values:
Key Assumptions:
Typical Light Source Kelvin Temperatures
Light Source Typical Kelvin (°K) Dominant Color Cast
Candle Flame 1800 – 2000 Orange/Yellow
Tungsten Household Bulb 2500 – 3000 Yellow/Orange
Sunrise/Sunset 2000 – 3000 Red/Orange
Fluorescent Light (Warm White) 3000 – 4000 Yellowish
Standard Daylight (Midday) 5000 – 5600 Neutral (Ideal)
Electronic Flash 5500 – 6000 Neutral (Ideal)
Cloudy Sky 6500 – 7500 Blue/Cool
Heavy Shade / North Sky 8000 – 10000 Strong Blue
Kelvin Temperature vs. Color Cast Simulation

What is Calculator White?

Calculator White refers to the process and tools used to accurately determine the correct color temperature setting, measured in Kelvin (K), for a camera or lighting system. Its primary purpose is to ensure that white objects in a scene are rendered as neutral white in the final image or video, regardless of the color cast of the ambient light source. Achieving accurate white balance is fundamental to professional photography and videography, as it forms the basis for correct color rendition. Without proper white balance, colors can appear unnatural, skewed towards blue, yellow, or other hues, leading to images that are aesthetically unpleasing or misleading.

Who should use it:

  • Photographers (DSLR, Mirrorless, Smartphone)
  • Videographers and Filmmakers
  • Live Streamers
  • Graphic Designers working with photographic assets
  • Anyone seeking to improve the color accuracy of their visual media

Common misconceptions:

  • "Auto White Balance (AWB) is always perfect." While AWB has improved significantly, it can still be fooled by dominant colors in a scene or unusual lighting. Manual or custom white balance often yields more predictable and accurate results.
  • "All fluorescent lights are the same." Fluorescent lights vary greatly in their spectral output and color temperature, often resulting in a greenish cast. Different types (cool white, warm white, daylight) require different adjustments.
  • "Higher Kelvin means warmer colors." In lighting and photography, higher Kelvin values (e.g., 6500K+) indicate cooler, bluer light, while lower Kelvin values (e.g., 2700K) indicate warmer, yellower light. This is counter-intuitive to how we perceive heat.

Calculator White Formula and Mathematical Explanation

The core of the Calculator White is understanding the relationship between the light source's color temperature and the desired white balance setting. While a physical "calculator" doesn't have a single complex formula like a loan amortization, it uses established principles of color temperature and color correction.

For this calculator, we simplify the process. The primary "calculation" is determining the necessary adjustment (often represented as a tint or color shift, and sometimes indirectly as an exposure adjustment for practical camera settings) needed to shift the perceived color of the light source towards the target white balance.

Mathematical Concepts Involved:

  • Color Temperature (Kelvin – K): A measure of the color of light emitted by an idealized black-body radiator when heated to a specific temperature. Lower K = warmer (yellow/red), Higher K = cooler (blue).
  • White Balance (WB): The process of removing unrealistic color casts, so that objects which appear white in person are rendered white in the photograph.
  • Tint/Shift: Often, white balance adjustments involve not just temperature (Kelvin) but also a green-magenta shift. This calculator primarily focuses on temperature, but acknowledges tint's importance.
  • Color Rendering Index (CRI): While not directly calculated here, CRI affects how accurately colors are reproduced under a given light source. Higher CRI is generally better.
  • Delta E (ΔE): A measure of the difference between two colors. A lower Delta E indicates colors are more similar. In white balance, we aim to minimize Delta E between the target white and the actual white rendered.

Simplified Calculation Logic:

The calculator assesses the difference between the Ambient Light Kelvin and the Desired White Balance Kelvin. This difference indicates the *magnitude* of the color shift required.

Color Shift Magnitude = |Ambient Light Kelvin - Desired White Balance Kelvin|

If Ambient Light Kelvin > Desired White Balance Kelvin, the ambient light is cooler (bluer), and the camera needs to be set warmer (more yellow). The opposite is true if Ambient Light Kelvin < Desired White Balance Kelvin.

The Tint Correction result is a conceptual representation of the adjustment needed. For example, a significant difference might require a substantial "warming" or "cooling" adjustment, which corresponds to moving the camera's WB slider towards yellow or magenta, respectively.

The Exposure Adjustment is a conceptual indicator. Sometimes, applying strong color filters or WB shifts can slightly alter the perceived brightness, though modern cameras handle this well. It's a reminder that WB is part of the overall exposure and color profile.

Delta E is estimated based on the Kelvin difference. A small difference in Kelvin results in a small Delta E (accurate WB), while a large difference results in a large Delta E (inaccurate WB).

Variables Table:

Variable Meaning Unit Typical Range
Ambient Light Kelvin Color temperature of the light source illuminating the scene. Kelvin (°K) 1800 K – 10000 K
Desired White Balance Kelvin Target color temperature for neutral white rendition. Kelvin (°K) 2500 K – 10000 K
Camera WB Preset Pre-defined white balance settings on the camera. N/A Auto, Daylight, Cloudy, etc.
Manual Kelvin Setting Direct Kelvin value set on the camera. Kelvin (°K) 2500 K – 10000 K
Tint Correction Conceptual adjustment needed for color cast (Warm/Cool). Qualitative / Scale e.g., Slight Warm, Strong Cool
Exposure Adjustment Conceptual impact on brightness due to WB settings. Qualitative / Stop e.g., Negligible, Slight Decrease
Delta E Color difference metric, indicates accuracy. Unitless (ΔE) 0 (Identical) – 100 (Very Different)

Practical Examples (Real-World Use Cases)

Example 1: Shooting Product Photos Under Office Lighting

Scenario: A photographer is taking product shots of jewelry indoors using standard office fluorescent lighting. They want the silver and gold to appear true to color.

Inputs:

  • Ambient Light Kelvin: 4000 °K (Warm White Fluorescent)
  • Desired White Balance Kelvin: 5500 °K (Standard Daylight/Flash for accurate color)
  • Camera White Balance Preset: Custom

Calculator Output:

  • Primary Result: Set Camera to 5500°K
  • Tint Correction: Moderate Warm Adjustment Needed
  • Exposure Adjustment: Negligible
  • Delta E: Low (Approx. 3-5)

Interpretation: The office lights have a yellowish cast (4000K). To make whites appear white and colors true, the photographer needs to set their camera to 5500K. The calculator indicates a significant shift towards warmer tones (more yellow) is required, but the impact on overall brightness is minimal. A Delta E of 3-5 suggests a good, but not perfect, match.

Example 2: Filming an Outdoor Interview on a Sunny Afternoon

Scenario: A videographer is filming an interview outdoors. It's a clear, sunny day, but there's a slight blue cast from the sky.

Inputs:

  • Ambient Light Kelvin: 5600 °K (Midday Daylight)
  • Desired White Balance Kelvin: 5600 °K (Matching Daylight for neutral rendering)
  • Camera White Balance Preset: Daylight

Calculator Output:

  • Primary Result: Camera WB set to 5600°K (or Daylight preset)
  • Tint Correction: No significant adjustment needed
  • Exposure Adjustment: Negligible
  • Delta E: Very Low (Approx. 1-2)

Interpretation: The camera's 'Daylight' preset is typically around 5500-5600K, matching the ambient conditions perfectly. The calculator confirms that no major adjustment is needed, resulting in a very accurate color rendition (low Delta E). If the videographer had accidentally set their camera to 'Tungsten' (around 3200K), the resulting footage would look very blue.

How to Use This Calculator White

Using the Calculator White is straightforward and designed to help you achieve precise color accuracy in your visual projects. Follow these steps:

  1. Identify Ambient Light Kelvin: Determine the color temperature of the primary light source in your scene. Use the table provided for common light sources or a dedicated light meter if available. Enter this value into the Ambient Light Kelvin (°K) field.
  2. Set Desired White Balance: Decide what color temperature you want your camera to consider "white." For most photographic purposes, 5500°K (standard daylight) is the ideal target. Enter this into the Desired White Balance Kelvin (°K) field.
  3. Select Camera Preset: Choose your camera's current white balance setting from the Camera White Balance Preset dropdown. If you plan to manually input a Kelvin value, select Custom.
  4. Enter Manual Kelvin (If Applicable): If you selected Custom, enter the specific Kelvin value you intend to set on your camera into the Manual Kelvin Setting field.
  5. Click Calculate: Press the Calculate White Balance button.

How to read results:

  • Primary Result: This is the key takeaway – it tells you the recommended Kelvin value (or preset) to set on your camera for the most neutral white balance.
  • Tint Correction: This gives a qualitative idea of whether you need to adjust the green-magenta balance on your camera, if applicable.
  • Exposure Adjustment: A reminder that WB settings can sometimes subtly affect perceived brightness.
  • Delta E: Indicates the expected accuracy of the white balance. Lower is better.
  • Key Assumptions: Reviews the inputs you provided, helping you confirm the basis of the calculation.
  • Formula Explanation: Briefly describes the underlying principles.

Decision-making guidance:

  • If the Ambient Light Kelvin is significantly different from your Desired White Balance Kelvin, you'll see a larger required adjustment.
  • Use the calculated value to set your camera's manual Kelvin (if supported) or choose the closest preset.
  • If your camera's Auto WB is failing, manually setting the WB based on these calculations will provide more consistent results.
  • For critical work, always shoot a test image and review the color balance, making fine-tuning adjustments as needed.

Key Factors That Affect Calculator White Results

While the Calculator White provides a strong starting point, several real-world factors can influence the actual outcome and the perceived accuracy of your white balance:

  1. Light Source Quality (CRI): Not all lights at the same Kelvin value are equal. A light source with a low Color Rendering Index (CRI) might produce a specific Kelvin temperature but render colors inaccurately. This calculator assumes a reasonably good quality light source.
  2. Multiple Light Sources: Scenes with mixed lighting (e.g., daylight through a window plus indoor tungsten bulbs) are challenging. The calculator typically works best for the dominant light source. You may need to choose a WB that compromises or use post-processing.
  3. Reflectance and Color Spill: The color of surrounding surfaces can bounce light back onto your subject, subtly influencing the perceived color. A red wall nearby can cast a reddish hue.
  4. Camera Sensor and Processing: Different camera sensors and image processing engines interpret light slightly differently. What appears neutral on one camera might be slightly off on another, even with the same WB setting.
  5. Human Perception vs. Measurement: Our eyes adapt to color casts, especially over time. What looks slightly off to our eyes might be measured accurately by a calculator, and vice-versa. The goal is often pleasing results, not just perfect measurement.
  6. Post-Processing Adjustments: Shooting in RAW format allows significant white balance adjustments later. This calculator helps set a good starting point in-camera, but post-processing offers final control. Understanding the initial color cast helps in making effective post-processing decisions.
  7. Dynamic Range Limitations: In scenes with very high contrast, achieving perfect white balance across all highlights and shadows simultaneously can be difficult.
  8. Specific Camera WB Presets: The exact Kelvin value associated with presets like 'Daylight' or 'Cloudy' can vary slightly between camera manufacturers.

Frequently Asked Questions (FAQ)

Q: What is the difference between 'Color Temperature' and 'White Balance'?

A: Color temperature (Kelvin) describes the color of a light source itself. White balance is the camera setting or process used to make white objects appear white in your photo, effectively neutralizing the color cast from the light source.

Q: Why does my camera's Auto White Balance (AWB) look wrong sometimes?

A: AWB tries to guess the correct setting based on the scene. If the scene has a dominant color (like a blue sky or a red blanket), AWB can be thrown off. It also struggles with mixed lighting or unusual light sources.

Q: Should I shoot in RAW or JPEG for white balance?

A: Shooting in RAW gives you the most flexibility to adjust white balance accurately in post-processing without significant quality loss. JPEG images have the white balance "baked in," making adjustments more difficult.

Q: How do I find the Kelvin value of my LED lights?

A: Check the manufacturer's specifications. LEDs are often rated in Kelvin (e.g., 3200K for warm, 5600K for daylight). Some are adjustable, allowing you to set a specific Kelvin value.

Q: What does a 'green cast' mean in photography?

A: A green cast means the image has an unwanted tint of green. This is common with some types of fluorescent lighting and can be corrected by adjusting the white balance towards magenta.

Q: Can I use this calculator for video lighting?

A: Absolutely. Accurate white balance is crucial for video to ensure consistent and pleasing colors throughout your footage. This calculator helps you set your lights and camera correctly.

Q: What is a "custom white balance"?

A: Custom white balance involves pointing your camera at a neutral white or gray card under your specific lighting conditions and telling the camera to use that image as the reference for white. This is often the most accurate method.

Q: Does screen brightness affect perceived white balance?

A: Screen brightness itself doesn't change the *color* of the white balance setting, but it can affect your *perception* of whether the white balance is correct. Adjusting screen brightness to match ambient light can help in judging color accuracy.

Related Tools and Internal Resources

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var lightSourceKelvinInput = document.getElementById('lightSourceKelvin'); var targetWhiteKelvinInput = document.getElementById('targetWhiteKelvin'); var cameraWBSettingInput = document.getElementById('cameraWBSetting'); var customKelvinValueInput = document.getElementById('customKelvinValue'); var customKelvinInputGroup = document.getElementById('customKelvinInputGroup'); var lightSourceKelvinError = document.getElementById('lightSourceKelvinError'); var targetWhiteKelvinError = document.getElementById('targetWhiteKelvinError'); var customKelvinValueError = document.getElementById('customKelvinValueError'); var resultsContainer = document.getElementById('resultsContainer'); var primaryResult = document.getElementById('primaryResult'); var tintCorrection = document.getElementById('tintCorrection'); var exposureAdjustment = document.getElementById('exposureAdjustment'); var deltaE = document.getElementById('deltaE'); var lightSourceInfo = document.getElementById('lightSourceInfo'); var targetSettingInfo = document.getElementById('targetSettingInfo'); var formulaExplanation = document.getElementById('formulaExplanation'); var kelvinChartCanvas = document.getElementById('kelvinChart').getContext('2d'); var chartInstance = null; // To hold the chart object // Default values for reset var defaultValues = { lightSourceKelvin: 5500, targetWhiteKelvin: 5500, cameraWBSetting: 'custom', customKelvinValue: 5500 }; // Function to validate input function validateInput(value, id, errorElement, min, max, label, isRequired = true) { var errorText = "; var isValid = true; if (isRequired && (value === null || value === " || isNaN(parseFloat(value)))) { errorText = label + ' is required.'; isValid = false; } else if (!isNaN(parseFloat(value))) { var numValue = parseFloat(value); if (numValue max) { errorText = label + ' must be no more than ' + max + '.'; isValid = false; } } if (errorElement) { errorElement.textContent = errorText; errorElement.style.display = isValid ? 'none' : 'block'; } return isValid; } // Function to update visibility of custom Kelvin input function updateCustomKelvinVisibility() { if (cameraWBSettingInput.value === 'custom') { customKelvinInputGroup.style.display = 'flex'; } else { customKelvinInputGroup.style.display = 'none'; // Clear error for custom Kelvin if not visible customKelvinValueError.textContent = "; customKelvinValueError.style.display = 'none'; } } // Function to map preset names to approximate Kelvin values for display/logic function getPresetKelvin(preset) { switch(preset) { case 'daylight': return 5500; case 'cloudy': return 6500; case 'shade': return 8000; case 'tungsten': return 3200; case 'fluorescent': return 4000; // Can vary widely, this is a common estimate case 'flash': return 5500; default: return 5500; // Default for Auto or unknown } } // Function to get qualitative tint correction function getTintCorrection(ambientK, targetK) { var diff = ambientK – targetK; if (Math.abs(diff) 300) return "Moderate Cool Adjustment Needed (Add Magenta)"; if (diff 150) return "Slight Cool Adjustment Needed"; if (diff < -150) return "Slight Warm Adjustment Needed"; return "Minimal adjustment needed"; // Fallback } // Function to estimate Delta E based on Kelvin difference // This is a very simplified approximation! Real Delta E is complex. function estimateDeltaE(ambientK, targetK) { var diff = Math.abs(ambientK – targetK); if (diff < 50) return "Very Low (Approx. 1-2)"; // Near perfect match if (diff < 200) return "Low (Approx. 3-5)"; if (diff < 500) return "Moderate (Approx. 6-10)"; if (diff 18)"; // Significant difference } // Function to get a qualitative description of color cast function getColorCastDescription(kelvin) { if (kelvin < 2500) return "Very Warm (Reddish-Orange)"; if (kelvin < 3500) return "Warm (Yellow-Orange)"; if (kelvin < 4500) return "Slightly Warm (Yellowish)"; if (kelvin < 6000) return "Neutral (Daylight)"; if (kelvin < 7500) return "Slightly Cool (Bluish)"; if (kelvin < 9000) return "Cool (Blue)"; return "Very Cool (Deep Blue)"; } function calculateWhiteBalance() { var ambientK = parseFloat(lightSourceKelvinInput.value); var targetK = parseFloat(targetWhiteKelvinInput.value); var wbPreset = cameraWBSettingInput.value; var customK = parseFloat(customKelvinValueInput.value); // Validation var isAmbientValid = validateInput(ambientK, 'lightSourceKelvin', lightSourceKelvinError, 1000, 15000, 'Ambient Light Kelvin'); var isTargetValid = validateInput(targetK, 'targetWhiteKelvin', targetWhiteKelvinError, 1000, 15000, 'Desired White Balance Kelvin'); var isCustomKValid = true; if (wbPreset === 'custom') { isCustomKValid = validateInput(customK, 'customKelvinValue', customKelvinValueError, 1000, 15000, 'Manual Kelvin Setting'); } if (!isAmbientValid || !isTargetValid || !isCustomKValid) { resultsContainer.style.display = 'none'; return; } var effectiveTargetK = (wbPreset === 'custom') ? customK : getPresetKelvin(wbPreset); var calculatedDeltaE = estimateDeltaE(ambientK, effectiveTargetK); var calculatedTint = getTintCorrection(ambientK, effectiveTargetK); var colorCast = getColorCastDescription(ambientK); // Determine the primary result message var mainResultText; var mainResultKelvin; if (wbPreset === 'custom') { mainResultKelvin = customK; mainResultText = "Set Camera to " + customK.toLocaleString() + "°K"; } else { mainResultKelvin = getPresetKelvin(wbPreset); mainResultText = "Use Camera Preset: " + wbPreset.charAt(0).toUpperCase() + wbPreset.slice(1); // Optionally show Kelvin for presets too if helpful // mainResultText += " (~" + getPresetKelvin(wbPreset).toLocaleString() + "°K)"; } // Update results display primaryResult.textContent = mainResultText; tintCorrection.innerHTML = "Tint Correction: " + calculatedTint; exposureAdjustment.innerHTML = "Exposure Adjustment: Negligible"; // Simplified for this calculator deltaE.innerHTML = "Estimated Delta E: " + calculatedDeltaE; lightSourceInfo.innerHTML = "Light Source: " + ambientK.toLocaleString() + "°K (" + colorCast + ")"; targetSettingInfo.innerHTML = "Target WB: " + effectiveTargetK.toLocaleString() + "°K"; formulaExplanation.innerHTML = "Formula Used: The calculator determines the difference between the ambient light Kelvin and the desired or set camera Kelvin. This difference dictates the necessary color temperature adjustment (warming or cooling) and provides an estimated color accuracy (Delta E)."; resultsContainer.style.display = 'block'; updateChart(ambientK, effectiveTargetK); } // Function to reset the form to default values function resetForm() { lightSourceKelvinInput.value = defaultValues.lightSourceKelvin; targetWhiteKelvinInput.value = defaultValues.targetWhiteKelvin; cameraWBSettingInput.value = defaultValues.cameraWBSetting; customKelvinValueInput.value = defaultValues.customKelvinValue; // Clear errors lightSourceKelvinError.textContent = "; lightSourceKelvinError.style.display = 'none'; targetWhiteKelvinError.textContent = "; targetWhiteKelvinError.style.display = 'none'; customKelvinValueError.textContent = "; customKelvinValueError.style.display = 'none'; resultsContainer.style.display = 'none'; updateCustomKelvinVisibility(); // Update visibility based on reset preset updateChart(); // Clear or reset chart } // Function to copy results function copyResults() { var resultText = "Calculator White Results:\n\n"; resultText += "Primary Recommendation: " + primaryResult.textContent.replace("Set Camera to ", "").replace("Use Camera Preset: ", "") + "\n"; resultText += document.getElementById('tintCorrection').textContent + "\n"; resultText += document.getElementById('exposureAdjustment').textContent + "\n"; resultText += document.getElementById('deltaE').textContent + "\n\n"; resultText += document.getElementById('lightSourceInfo').textContent + "\n"; resultText += document.getElementById('targetSettingInfo').textContent + "\n\n"; resultText += "Assumptions: Calculations based on provided inputs.\n"; resultText += "Formula: Difference between ambient light Kelvin and target/set Kelvin determines adjustment.\n"; // Use a temporary textarea to copy text var textArea = document.createElement("textarea"); textArea.value = resultText; textArea.style.position = "fixed"; // Avoid scrolling to bottom of page in MS Edge. textArea.style.opacity = "0"; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied to clipboard!' : 'Failed to copy results.'; // Optionally show a temporary message to the user var statusEl = document.createElement('div'); statusEl.textContent = msg; statusEl.style.position = 'fixed'; statusEl.style.bottom = '20px'; statusEl.style.left = '50%'; statusEl.style.transform = 'translateX(-50%)'; statusEl.style.backgroundColor = successful ? 'var(–success-color)' : '#dc3545'; statusEl.style.color = 'white'; statusEl.style.padding = '10px 20px'; statusEl.style.borderRadius = '5px'; statusEl.style.zIndex = '1000'; document.body.appendChild(statusEl); setTimeout(function(){ document.body.removeChild(statusEl); }, 2000); } catch (err) { console.error('Fallback: Oops, unable to copy', err); // Optionally show error message var statusEl = document.createElement('div'); statusEl.textContent = 'Copying failed. Please copy manually.'; statusEl.style.position = 'fixed'; statusEl.style.bottom = '20px'; statusEl.style.left = '50%'; statusEl.style.transform = 'translateX(-50%)'; statusEl.style.backgroundColor = '#dc3545'; statusEl.style.color = 'white'; statusEl.style.padding = '10px 20px'; statusEl.style.borderRadius = '5px'; statusEl.style.zIndex = '1000'; document.body.appendChild(statusEl); setTimeout(function(){ document.body.removeChild(statusEl); }, 2000); } document.body.removeChild(textArea); } // Function to draw or update the chart function updateChart(ambientK = 5500, targetK = 5500) { if (chartInstance) { chartInstance.destroy(); // Destroy previous chart instance } var ctx = kelvinChartCanvas; var chartData = { labels: ['Light Source', 'Target WB'], datasets: [{ label: 'Color Temperature (°K)', data: [ambientK, targetK], backgroundColor: [ getColorForKelvin(ambientK, 0.6), // Use transparency for source getColorForKelvin(targetK, 0.8) // More opaque for target ], borderColor: [ 'rgba(255, 206, 86, 1)', // Yellow border for source 'rgba(75, 192, 192, 1)' // Green/Cyan border for target ], borderWidth: 2, borderSkipped: 'bottom' // Draw border only on top for bar chart feel }] }; chartInstance = new Chart(ctx, { type: 'bar', data: chartData, options: { responsive: true, maintainAspectRatio: true, scales: { y: { beginAtZero: false, title: { display: true, text: 'Color Temperature (°K)', color: 'var(–primary-color)' }, ticks: { // Suggest appropriate ticks based on common ranges callback: function(value, index, values) { if (value === 0) return '0°K'; // Avoid showing 0 if not in range return value.toLocaleString() + '°K'; } } }, x: { title: { display: true, text: 'Setting', color: 'var(–primary-color)' } } }, plugins: { legend: { display: false // Hide legend as labels are on bars }, tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || "; if (label) { label += ': '; } if (context.parsed.y !== null) { label += context.parsed.y.toLocaleString() + '°K'; } return label; } } } } } }); } // Helper function to get a representative color for a Kelvin value // This is a simplified visual approximation, not a perfect color mapping function getColorForKelvin(kelvin, alpha = 1) { var r, g, b; if (kelvin < 2000) { // Reddish r = 255; g = Math.max(0, 255 – (kelvin – 1800) * 5); b = 0; } else if (kelvin < 3500) { // Yellow/Orange r = 255; g = Math.max(0, 255 – (kelvin – 3000) * 2); b = Math.min(255, (kelvin – 2000) * 0.5); } else if (kelvin < 5500) { // Yellowish-White r = 255; g = Math.min(255, 255 – (kelvin – 3500) * 0.1); b = Math.min(255, (kelvin – 3500) * 0.1); } else if (kelvin < 7500) { // Neutral to Bluish-White r = Math.min(255, 255 – (kelvin – 5500) * 0.1); g = Math.min(255, 255 – (kelvin – 5500) * 0.05); b = 255; } else { // Blue r = Math.max(0, 255 – (kelvin – 8000) * 0.2); g = Math.max(0, 255 – (kelvin – 8000) * 0.1); b = 255; } // Clamp values r = Math.max(0, Math.min(255, r)); g = Math.max(0, Math.min(255, g)); b = Math.max(0, Math.min(255, b)); return "rgba(" + Math.round(r) + "," + Math.round(g) + "," + Math.round(b) + "," + alpha + ")"; } // Event listeners lightSourceKelvinInput.addEventListener('input', calculateWhiteBalance); targetWhiteKelvinInput.addEventListener('input', calculateWhiteBalance); cameraWBSettingInput.addEventListener('change', function() { updateCustomKelvinVisibility(); calculateWhiteBalance(); }); customKelvinValueInput.addEventListener('input', calculateWhiteBalance); // Initial setup window.onload = function() { updateCustomKelvinVisibility(); calculateWhiteBalance(); // Calculate on load with default values // Add Chart.js script if not already present (or assume it's available) // For a single file, you'd typically include it directly. Assuming it's globally available or embedded. if (typeof Chart === 'undefined') { var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js'; script.onload = function() { calculateWhiteBalance(); // Recalculate after chart library loads }; document.head.appendChild(script); } else { calculateWhiteBalance(); // Calculate immediately if Chart.js is already loaded } };

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