Calculator with Camera

Depth of Field Calculator

Full Frame (36x24mm) APS-C (Nikon/Sony) APS-C (Canon) Micro Four Thirds Custom
function updateCoC() { var sensorType = document.getElementById("sensorType").value; var customCoCGroup = document.getElementById("customCoCGroup"); var circleOfConfusionInput = document.getElementById("circleOfConfusion"); if (sensorType === "custom") { customCoCGroup.style.display = "block"; } else { customCoCGroup.style.display = "none"; circleOfConfusionInput.value = sensorType; // Set CoC based on selected sensor type } } function calculateDoF() { var focalLength = parseFloat(document.getElementById("focalLength").value); var aperture = parseFloat(document.getElementById("aperture").value); var subjectDistance = parseFloat(document.getElementById("subjectDistance").value); var circleOfConfusion = parseFloat(document.getElementById("circleOfConfusion").value); var resultDiv = document.getElementById("dofResult"); resultDiv.innerHTML = ""; // Clear previous results // Input validation if (isNaN(focalLength) || focalLength <= 0) { resultDiv.innerHTML = "Please enter a valid Focal Length (mm)."; return; } if (isNaN(aperture) || aperture <= 0) { resultDiv.innerHTML = "Please enter a valid Aperture (f-number)."; return; } if (isNaN(subjectDistance) || subjectDistance <= 0) { resultDiv.innerHTML = "Please enter a valid Subject Distance (meters)."; return; } if (isNaN(circleOfConfusion) || circleOfConfusion <= 0) { resultDiv.innerHTML = "Please enter a valid Circle of Confusion (mm)."; return; } // Convert subject distance to mm for calculations var s_mm = subjectDistance * 1000; // Calculate Hyperfocal Distance (H) in mm // H = f^2 / (N * c) var H_mm = (focalLength * focalLength) / (aperture * circleOfConfusion); // Calculate Near Focus Limit (Nf) in mm // Nf = (H * s) / (H + s – f) var numerator_Nf = H_mm * s_mm; var denominator_Nf = H_mm + s_mm – focalLength; var Nf_mm; if (denominator_Nf <= 0) { Nf_mm = 0; // Effectively everything from the camera is in focus up to infinity } else { Nf_mm = numerator_Nf / denominator_Nf; } // Calculate Far Focus Limit (Ff) in mm // Ff = (H * s) / (H – s – f) var numerator_Ff = H_mm * s_mm; var denominator_Ff = H_mm – s_mm – focalLength; var Ff_mm; var farLimitIsInfinity = false; if (denominator_Ff <= 0) { // Subject is at or beyond hyperfocal distance Ff_mm = Infinity; farLimitIsInfinity = true; } else { Ff_mm = numerator_Ff / denominator_Ff; } // Convert results to meters var H_m = H_mm / 1000; var Nf_m = Nf_mm / 1000; var Ff_m = farLimitIsInfinity ? "Infinity" : (Ff_mm / 1000).toFixed(2); // Calculate Total Depth of Field var totalDoF_m; if (farLimitIsInfinity) { totalDoF_m = "Infinity"; } else { totalDoF_m = (Ff_mm – Nf_mm) / 1000; totalDoF_m = totalDoF_m.toFixed(2); } // Ensure Near Focus Limit is not negative (can happen with very close subjects and large DoF) if (Nf_m < 0) Nf_m = 0; // Display results var resultsHTML = "

Calculation Results:

"; resultsHTML += "Hyperfocal Distance: " + H_m.toFixed(2) + " meters"; resultsHTML += "Near Focus Limit: " + Nf_m.toFixed(2) + " meters"; resultsHTML += "Far Focus Limit: " + Ff_m + (farLimitIsInfinity ? "" : " meters") + ""; resultsHTML += "Total Depth of Field: " + totalDoF_m + (farLimitIsInfinity ? "" : " meters") + ""; resultDiv.innerHTML = resultsHTML; } // Initialize CoC based on default sensor type document.addEventListener('DOMContentLoaded', function() { updateCoC(); }); .calculator-container { background-color: #f9f9f9; border: 1px solid #ddd; padding: 20px; border-radius: 8px; max-width: 600px; margin: 20px auto; font-family: Arial, sans-serif; } .calculator-container h2 { text-align: center; color: #333; margin-bottom: 20px; } .calc-input-group { margin-bottom: 15px; } .calc-input-group label { display: block; margin-bottom: 5px; font-weight: bold; color: #555; } .calc-input-group input[type="number"], .calc-input-group select { width: calc(100% – 22px); padding: 10px; border: 1px solid #ccc; border-radius: 4px; font-size: 16px; } .calculator-container button { display: block; width: 100%; padding: 12px; background-color: #007bff; color: white; border: none; border-radius: 4px; font-size: 18px; cursor: pointer; transition: background-color 0.3s ease; margin-top: 20px; } .calculator-container button:hover { background-color: #0056b3; } .calc-result { margin-top: 25px; padding: 15px; background-color: #e9f7ef; border: 1px solid #d4edda; border-radius: 4px; color: #155724; } .calc-result h3 { color: #155724; margin-top: 0; margin-bottom: 10px; } .calc-result p { margin-bottom: 8px; line-height: 1.5; } .calc-result p strong { color: #0c3d1e; } .error { color: #dc3545; font-weight: bold; background-color: #f8d7da; border: 1px solid #f5c6cb; padding: 10px; border-radius: 4px; }

Understanding Depth of Field in Photography

Depth of Field (DoF) is a fundamental concept in photography that refers to the distance between the nearest and farthest objects in an image that appear acceptably sharp. Mastering DoF allows photographers to control what parts of their image are in focus, enabling creative effects like isolating a subject from a blurry background (shallow DoF) or keeping an entire landscape sharp (deep DoF).

Key Factors Influencing Depth of Field:

  1. Aperture (f-number): This is the most significant factor. A wider aperture (smaller f-number like f/1.8, f/2.8) results in a shallower DoF, meaning less of the scene will be in focus. A narrower aperture (larger f-number like f/11, f/16) produces a deeper DoF, keeping more of the scene sharp.
  2. Focal Length: Longer focal lengths (telephoto lenses) tend to produce a shallower DoF compared to shorter focal lengths (wide-angle lenses) at the same aperture and subject distance.
  3. Subject Distance: The closer your camera is to your subject, the shallower the DoF will be. Conversely, increasing the distance between the camera and the subject will increase the DoF.
  4. Sensor Size / Circle of Confusion (CoC): Larger camera sensors (e.g., Full Frame) inherently produce a shallower DoF than smaller sensors (e.g., APS-C, Micro Four Thirds) when using the same effective focal length and aperture. The Circle of Confusion (CoC) is a measure of the largest blur spot that is still perceived as a sharp point by the human eye in a print of a certain size viewed at a certain distance. Different sensor sizes have different standard CoC values.

What is Hyperfocal Distance?

The Hyperfocal Distance is a specific focusing distance that maximizes the depth of field. When you focus your lens at its hyperfocal distance, everything from half of that distance all the way to infinity will appear acceptably sharp. This technique is particularly useful in landscape photography where you want to ensure both foreground and background elements are in focus.

How to Use the Depth of Field Calculator:

Our Depth of Field Calculator helps you predict the DoF for your specific camera and lens setup. Simply input the following values:

  • Focal Length (mm): The focal length of the lens you are using (e.g., 50mm, 85mm, 200mm).
  • Aperture (f-number): The f-stop you plan to use (e.g., f/2.8, f/8, f/16).
  • Subject Distance (meters): The distance from your camera to your main subject.
  • Sensor Type: Select your camera's sensor type from the dropdown. This will automatically set a standard Circle of Confusion (CoC) value. You can also choose 'Custom' to input your own CoC value if you know it.

The calculator will then provide you with:

  • Hyperfocal Distance: The distance at which to focus to achieve maximum DoF.
  • Near Focus Limit: The closest point to the camera that will be acceptably sharp.
  • Far Focus Limit: The farthest point from the camera that will be acceptably sharp (or "Infinity" if everything beyond a certain point is sharp).
  • Total Depth of Field: The total range of distance that is in acceptable focus.

Example Scenarios:

Let's consider a few examples using common camera settings:

Example 1: Portrait Photography (Shallow DoF)

  • Focal Length: 85mm
  • Aperture: f/1.8
  • Subject Distance: 2 meters
  • Sensor Type: Full Frame
  • Expected Result: A very shallow DoF, perhaps only a few centimeters, effectively blurring the background.

Example 2: Landscape Photography (Deep DoF)

  • Focal Length: 24mm
  • Aperture: f/11
  • Subject Distance: 5 meters
  • Sensor Type: APS-C (Nikon/Sony)
  • Expected Result: A much deeper DoF, potentially extending from a few meters to infinity, keeping most of the landscape sharp.

Example 3: Macro Photography (Extremely Shallow DoF)

  • Focal Length: 100mm
  • Aperture: f/2.8
  • Subject Distance: 0.3 meters (30 cm)
  • Sensor Type: Full Frame
  • Expected Result: An extremely shallow DoF, often measured in millimeters, making precise focusing critical.

Use this calculator to experiment with different settings and understand how they impact your image's depth of field, helping you achieve your desired photographic vision.

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