Video with Linux

Camcorder Depth of Field

There are already a number of online depth of field calculators such as Don Fleming's DOFMaster and Canon's Calculate Depth of Field. This page is specifically designed for computing the depth of field for consumer camcorders shooting both standard definition and high definition video. If your camcorder is not listed as one of the presets select Custom and manually specify the sensor size and the minimum and maximum focal lengths of the lens.

Image size in millimeters is approximated by multiplying the sensor size in inches by 16. The circle of confusion is 1/500 of the image size for standard definition and 1/1000 for high definition video. The depth of field is then calculated using the equations given by KerryG.

Camcorder Information

Camcorder
Sensor Size inches
Min focal length mm
Max focal length mm

Shooting Conditions

zoom x
aperture f-stop
object distance feet

Depth of Field Calculations

SD Circle of ConfusionUnknown Depth of FieldUnknown
HD Circle of ConfusionUnknown Depth of FieldUnknown

Conclusions

Originally the sensor size of a video camera referred to the diameter of the video pickup tube. The diagonal measurement of the photocathode on which the image was focused was typically about 2/3 the diameter of the tube. For example, a 1 inch diameter vidicon tube captured an image with a diagonal measurement of 0.63 inches or 16mm. Today, any video sensor designed to capture a 16mm image is said to have a sensor size of 1 inch.

Rather than implement a lookup table of common image sensor sizes, the computations used here estimate the diagonal measurement of the image in millimeters by multiplying the sensor size by 16. This gives exact results for 1", 1/2" sensors and results to within 2% for many consumer camcorders. Note, however, this approximation underestimates by 11% the image captured by a 1/3" sized sensor.

Another way to obtain the size of the captured image is by multiplying 43.3 by the actual focal length and then dividing by the equivalent 35mm focal length. The equivalent 35mm focal length may be reported by the manufacturer or measured experimentally. For more information see how to calculate 35mm equivalent focal length by George Kroonder.


Page written and maintained by Eric Olson
Last Updated: Sun Sep 20 15:57:16 PDT 2009