Last Updated 5 hours ago
Filmmaking Dictionary: Number 2 / 29.97 fps
Definition
29.97 fps is the common shorthand for 30,000/1,001 frames per second, approximately 29.97002997. It is a fractional rate associated with North American colour-video timing and is slightly slower than true 30.000 fps.
The label alone does not say whether the picture is progressive or interlaced. A production must specify the full format, including how the images or fields are recorded and presented.
29.97 Versus 30
The two rates differ by a factor of 1.001. If a sequence of frames intended for 29.97 is played at 30, it runs 0.1% faster. Over an hour, a mismatch of that scale amounts to roughly 3.6 seconds.
That is enough to create a clear synchronization problem in a long take. A camera menu that rounds the setting to ’30p’ should be checked against the manufacturer’s explanation and the recorded file’s actual rate.
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Drop-Frame Timecode
Drop-frame timecode compensates for the difference between the fractional frame rate and a whole-number timecode count by skipping selected frame numbers. It does not remove recorded pictures. Non-drop-frame timecode counts sequential frame labels without that adjustment.
At 29.97, these numbering systems can describe the same underlying stream of images while producing different timecode readings over time. Selecting drop-frame does not turn the recording into 30 fps and does not fix a file that has been interpreted at the wrong playback speed.
Progressive Frames and Interlaced Fields
A 29.97p recording contains approximately 29.97 complete frames each second. A conventional 59.94-field interlaced signal has two fields per frame pair. Those fields can capture different instants, so deinterlacing and conversion need to account for their temporal relationship.
Practical Checks
- Confirm whether ’30’ in the camera menu means 29.97 or 30.000.
- Agree on drop-frame or non-drop-frame timecode where relevant.
- Match the audio and camera synchronization plan.
- Check the intended sequence and delivery format before editing.
- Review a long test for drift if different devices or applications are involved.
Common Mistakes
A frequent mistake is to treat ‘drop-frame’ as a description of damaged video or missing frames. Another is to repair only the starting offset of a clip whose timing actually drifts. A constant offset and a speed mismatch need different corrections.
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Frequently Asked Questions
Does 29.97 mean the camera skips frames at random?
No. It is a consistent recording or playback rate.
Is 29.97 the same as 59.94?
No. Specify whether the number refers to progressive frames or interlaced fields, and use the full format description.
Related Terms
Browse all terms starting with 2 or return to the filmmaking dictionary.