How Can I Increase the Frame Rate of My Camcorder?

by Andrew Alexander
Published on Dec 16, 2001 12:00 AM



This question comes up from time to time on the message board and on the internet. It is asked by people who hear about how Hollywood produces those great slow-motion sequences in major motion pictures. In Hollywood, movies are shot they put a big roll of film into the camera and have it record at a very fast frame rate, and then play it back at regular speed. The effect is slow motion. In camcorder land, it’s impossible to get slow motion this way. Now we find out why.

Part of the problem here is that people new to camcorders confuse shutter speed with frame rate. The frame rate of a camcorder is the number of times every second that the camera takes a picture of the world it sees. The shutter speed represents how long the frame stays open for to record any particular image. The shutter speed on camcorders is variable; the frame rate is not. For example, you would use a slow shutter speed in low-light situations to let in more light, but in bright situations you would use a fast shutter speed to restrict the amount of light coming in.

A film camera is a lot more versatile than a camcorder, mostly because you don’t need to configure a film camera to connect to a television. Since a camcorder must connect to a television, it must share the same frame rate that the television displays, which is (basically) thirty frames per second. Camcorders are built from the ground up to conform to this standard, and it is impossible to change.

However, it’s not impossible to get slow-motion in videography. When editing video on the computer, many editing programs have speed and duration options. For example, you could change a scene which originally lasts ten seconds to 50% speed, in which case it would now take twenty seconds. This is accomplished by the computer repeating every frame twice as the sequence is played, ie:

Original sequence:ABCDEFGHIJ...
New sequence:AABBCCDDEE...

In the same regard, you could also speed up the frame rate by having the sequence play every other frame, ie:

Original sequence:ABCDEFGHIJ...
New sequence:ACEGHJLNPR...