Anamorphic Lens Calculator
Determine the final aspect ratio and desqueezed resolution of your footage when shooting with an anamorphic lens. This tool is essential for cinematographers and editors to plan their workflow and visualize the final cinematic frame.
What is an Anamorphic Lens?
An anamorphic lens is a specialized piece of optics used in cinematography to create a widescreen image on standard film or a digital sensor. Unlike a standard "spherical" lens which projects a circular image, an anamorphic lens horizontally compresses (or "squeezes") the image by a specific factor. This squeezed image is then stretched back out ("desqueezed") in post-production or by a projector to reveal an ultra-wide aspect ratio, famously associated with epic cinema.
Understanding Key Anamorphic Terms
Squeeze Factor
The squeeze factor is the most critical property of an anamorphic lens. It defines how much the image is horizontally compressed. Common squeeze factors include:
- 1.33x: Often used with 16:9 sensors to achieve a cinematic 2.39:1 aspect ratio.
- 1.5x: A popular choice for balancing anamorphic character with usability.
- 1.8x: Creates a very wide image, close to the classic CinemaScope look.
- 2.0x: The traditional Hollywood standard, designed for 4:3 film frames to produce a ~2.39:1 image.
Desqueezing
Desqueezing is the process of digitally stretching the horizontally compressed footage back to its intended proportions. If you record with a 2x anamorphic lens, you must stretch the width of the footage by 200% in your editing software to see the correct image. Our calculator does this math for you, showing you the final resolution and aspect ratio you'll be working with.
Aspect Ratio
Aspect ratio is the ratio of an image's width to its height. A standard HD television is 16:9 (or 1.78:1). Anamorphic lenses are used to achieve much wider, more cinematic aspect ratios, such as 2.39:1, often referred to as "Scope" or CinemaScope.
How to Use the Anamorphic Calculator
Using the calculator is straightforward. You need three pieces of information from your camera and lens:
- Sensor Width (px): Enter the horizontal resolution of the sensor mode you are recording in. For example, for 4K DCI, this is often 4096 pixels.
- Sensor Height (px): Enter the vertical resolution of your sensor mode. For 4K DCI, this is 2160 pixels.
- Anamorphic Squeeze Factor: Enter the squeeze factor of your lens, such as
1.33,1.8, or2.
After entering the values, click "Calculate Final Image" to see the results.
Practical Example
Let's say you are shooting with a Blackmagic Pocket Cinema Camera 4K in its 4K DCI mode and using a popular 1.33x anamorphic lens.
- Sensor Width:
4096px - Sensor Height:
2160px - Squeeze Factor:
1.33
The calculator will first determine the desqueezed width: 4096 * 1.33 = 5447.68. It then calculates the final aspect ratio: 5447.68 / 2160 = 2.52. The result is a final image with a resolution of approximately 5448 x 2160 and a cinematic aspect ratio of 2.52:1, which is even wider than the standard CinemaScope.
Why Shoot Anamorphic?
Beyond the widescreen aspect ratio, anamorphic lenses are prized for their unique visual characteristics that are difficult to replicate digitally. These include:
- Oval Bokeh: Out-of-focus points of light appear as vertical ovals instead of circles.
- Horizontal Lens Flares: Bright light sources create distinctive, streak-like horizontal flares across the frame.
- Unique Distortion: Anamorphic lenses have a unique field of view, creating a subtle distortion and painterly quality that many filmmakers find appealing.
This calculator helps you take the first step in mastering this beautiful format by removing the guesswork from your technical setup.
Error
Please enter valid, positive numbers for all fields.'; return; } // 3. Perform calculations var desqueezedWidth = sensorWidth * squeezeFactor; var finalAspectRatio = desqueezedWidth / sensorHeight; var sensorAspectRatio = sensorWidth / sensorHeight; // 4. Format output var sensorAspectRatioString = "; if (Math.abs(sensorAspectRatio – (16/9)) < 0.01) { sensorAspectRatioString = '1.78:1 (16:9)'; } else if (Math.abs(sensorAspectRatio – (4/3)) < 0.01) { sensorAspectRatioString = '1.33:1 (4:3)'; } else { sensorAspectRatioString = sensorAspectRatio.toFixed(2) + ':1'; } var resultHTML = 'Calculation Results
' + 'Final Desqueezed Resolution: ' + Math.round(desqueezedWidth) + ' x ' + sensorHeight + ' px' + 'Final Aspect Ratio: ' + finalAspectRatio.toFixed(2) + ':1' + '' + 'Original Sensor Aspect Ratio: ' + sensorAspectRatioString + "; // 5. Display results resultDiv.style.display = 'block'; resultDiv.style.backgroundColor = '#eaf5ff'; resultDiv.style.borderColor = '#b3d7f2'; resultDiv.innerHTML = resultHTML; }