Frame line calculator
Find where a delivery aspect ratio sits on your camera's recording area. Choose the target ratio and the calculator gives the frame line size in millimeters and, where the manufacturer publishes it, in pixels, plus how much of the sensor it uses and how much is left outside.
A drawing shows the frame on the recording area. Use it to set up frame lines, plan a vertical or square crop from a wide recording, or check what an anamorphic squeeze gives you.
How to use it
- Camera: choose the camera and recording mode; its area and resolution set the result.
- Target aspect ratio: any ratio, such as 2.39, 1.85, 16:9, 4:5 or 9:16.
- Squeeze factor: 1 for spherical lenses; 1.3 to 2 for anamorphics.
- Frame line size: 100% uses the largest frame that fits; lower values leave a margin for protection or extraction.
Example
On an ALEXA 35 in 4.6K 3:2 Open Gate (27.99 × 19.22 mm, 4608 × 3164), a 2.39:1 frame line is 27.99 × 11.71 mm, or 4608 × 1928 pixels. It uses about 61% of the recording area, leaving about 19.5% above and below.
Good to know
The crop factor is measured on the frame line, against the 36 × 24 mm full frame diagonal, so it shows how the lens frames inside that frame line. Pixel sizes are rounded to even numbers.