What does timecode do that a clapperboard does not?

A clapperboard gives one alignment point, after which camera and recorder clocks drift apart at whatever rate they differ. Timecode embeds a shared running clock in every file, so the alignment holds for the entire take no matter how long it runs. It also syncs the takes nobody managed to slate, which is most of documentary work.

Setting every timecode box to the same value from one master, usually by briefly cabling them together, which takes about a minute for a whole kit. Each box then free-runs on its own crystal. With a good box holding about one frame of drift per twenty four hours, a single jam at the start of the day keeps everything frame accurate until wrap.

What is the difference between drop frame and non-drop frame?

North American broadcast rates are 29.97 and 59.94 rather than exactly 30 and 60, so timecode counting at 30 runs ahead of real time. Drop frame skips certain frame numbers, not actual frames, to keep timecode aligned with clock time. Non-drop counts every number and drifts about 3.6 seconds per hour. Use drop frame when running time matters, and be consistent across a project.

How many timecode boxes do I need?

One per device that records, including every camera and every audio recorder. A box not attached to a device does nothing, which is why three-box kits are usually better value than buying singles. Some recorders and cinema cameras generate and output timecode themselves, in which case that unit becomes the master and needs no box of its own.

Is free waveform sync good enough?

For single camera work with takes of a few minutes, yes, and it is accurate. It becomes unreliable on long takes where clock drift accumulates, in noisy environments where the camera scratch track is poor, and on multi-camera shoots where everything must cut together across a whole day. Those three thresholds are where timecode starts paying for itself.

Timecode and Sync Guide: Jam Syncing, Drift and Dual System Sound

Short answer

Timecode embeds a shared running clock into every recording so editing software aligns picture and sound automatically and keeps them locked for the whole take. Jam sync all devices from one master at the start of the day, and a good box holding roughly one frame of drift per twenty four hours stays frame accurate until wrap.

A clapperboard gives an editor one point where picture and sound agree, and everything after that drifts. Timecode removes drift entirely by embedding a shared clock in every file. The Deity TC-1 Timecode Box at around $135 a box makes that affordable enough to put one on every device, which is the only configuration where timecode actually helps.

What timecode is

Timecode is a clock value embedded in a recording, expressed as hours, minutes, seconds and frames. When two devices carry the same timecode, editing software can place both on a timeline at the correct offset with no analysis of the content at all, and they remain aligned for the entire length of the take.

This is different from waveform sync, which analyses the audio in both files and finds the offset where they match. Waveform sync is clever and free and it produces one alignment point, after which the two files drift apart at whatever rate their clocks differ.

On a two minute take the drift is invisible. On a forty minute interview it is a visible lip sync error at the end, and the editor ends up nudging and re-syncing repeatedly. That length threshold is the practical dividing line between needing timecode and not.

Jam syncing, and why once a day works

Jam syncing means setting all the timecode boxes to the same value from one master, usually by cabling them together briefly or by connecting them to a designated master unit. It takes about a minute for a whole kit.

After that, each box free-runs on its own crystal oscillator. A good modern box holds roughly one frame of drift per twenty four hours, which is about 0.5 parts per million. With that accuracy, a jam at the start of the day leaves everything frame-accurate at wrap, which is why once a day is the normal routine.

Camera internal clocks are far worse, commonly drifting several frames per hour. That is why syncing cameras to each other using their own clocks does not work and why a dedicated box is required rather than merely convenient.

How timecode reaches each device

Device	Connection	What it costs you
Cinema camera with a TC port	Direct, over BNC or a dedicated port	Nothing. This is the ideal case
Mirrorless with no TC input	As an audio signal on one channel	One audio channel, permanently
Audio recorder	Direct, on a timecode input	Nothing
Recorder with no TC input	As an audio signal on one channel	One input channel
Devices with neither	Waveform sync instead	Editing time, and accuracy on long takes

The second row is where most people live. On a mirrorless body without a timecode input, the box feeds a timecode signal into one audio channel and editing software reads it from the waveform. It works reliably and costs you a channel that could have carried a safety audio track, which on a two channel camera is a genuine trade and a large part of why cinema bodies with a real timecode port command a premium.

Boxes, singly and in sets

$135 to $399. Buy one per recording device, which is why the three-box kits are usually better value than singles.

Starter pick $135

Deity

Deity TC-1 Timecode Box

A single 0.5 ppm timecode box with Bluetooth setup, which is the cheapest way to stop syncing by clap in post.

Accuracy: 0.5 ppm

You need at least two to be useful.

Check price

Best value $373

Deity

Deity TC-1 Three-Box Kit

Three boxes covers two cameras and a recorder, which is the actual shape of most small multicam shoots.

Units: 3

The value pick for two-camera interviews.

Check price

Expert choice $399

SUAREA

Tentacle Sync E MKII (Standard Set)

Two units with the cables that actually fit common cameras, which is where most timecode purchases quietly go wrong.

Units: 2

Check your camera's connector before ordering.

Check price

Drop frame and non-drop frame

This confuses people permanently and the concept is simple. North American broadcast frame rates are not exactly 30 or 60 frames per second, they are 29.97 and 59.94, a legacy of adding colour to black and white television. That means timecode counting at 30 frames per second gradually runs ahead of real elapsed time.

Drop frame timecode compensates by skipping certain frame numbers, not frames themselves, so the timecode value stays aligned with real clock time. It skips two frame numbers each minute except every tenth minute, which brings the error to nearly zero over an hour.

Non-drop frame counts every number sequentially and drifts from wall clock time by about 3.6 seconds per hour. Neither is wrong; they answer different questions. Use drop frame when broadcast running time matters, non-drop when frame counting matters, and above all be consistent across a project, because mixing them is where the confusion becomes an actual problem.

A working routine

Charge every box the night before. They free-run continuously and discharge on the shelf as well as on the shoot.
Jam all boxes from one master at the start of the day, and note the time you did it.
Set the same frame rate and drop frame mode on every device. A frame rate mismatch defeats the whole system.
Mount each box in a cold shoe or on a small arm where its cable does not cross a battery door or a hinge.
Label every box so a sync problem can be traced to a specific unit rather than to three identical black boxes.
Re-jam after lunch on a long day or after a large temperature change, because crystal drift varies with temperature.
Record a camera scratch track anyway, always, as the fallback when something in the chain fails.

The last item is the one that matters when the system fails, and systems fail. A Gaffer Power Black Gaffer Tape, 2 inch roll and a marker covers the labelling item, and it is worth doing on day one rather than during the first sync problem.

When you do not need timecode

Single camera with in-camera audio needs nothing, because picture and sound came from the same clock and are already locked. This describes a lot of solo work, and buying timecode for it is solving a problem that does not exist.

Short takes with dual-system sound usually do not need it either. Waveform sync is accurate and free on takes of a few minutes, and it handles the common documentary case perfectly well.

Timecode earns its price at three thresholds: takes long enough that drift accumulates, multiple cameras that must cut together, and any project where the volume of material makes manual syncing a significant part of the schedule. Below those, the money belongs in sound rather than in synchronising it.

Next, from here

Best timecode generators
The boxes, compared.
Timecode and frame rate calculator
Drop frame maths and running time.
Best field recorders
Which accept timecode directly.
Media workflow and backup
What happens to synced files afterwards.
Audio for video guide
Why dual system sound exists at all.
Run and gun pro build
The tier where timecode becomes standard.

Common questions

What does timecode do that a clapperboard does not?: A clapperboard gives one alignment point, after which camera and recorder clocks drift apart at whatever rate they differ. Timecode embeds a shared running clock in every file, so the alignment holds for the entire take no matter how long it runs. It also syncs the takes nobody managed to slate, which is most of documentary work.
What is jam syncing?: Setting every timecode box to the same value from one master, usually by briefly cabling them together, which takes about a minute for a whole kit. Each box then free-runs on its own crystal. With a good box holding about one frame of drift per twenty four hours, a single jam at the start of the day keeps everything frame accurate until wrap.
What is the difference between drop frame and non-drop frame?: North American broadcast rates are 29.97 and 59.94 rather than exactly 30 and 60, so timecode counting at 30 runs ahead of real time. Drop frame skips certain frame numbers, not actual frames, to keep timecode aligned with clock time. Non-drop counts every number and drifts about 3.6 seconds per hour. Use drop frame when running time matters, and be consistent across a project.
Can I use timecode on a camera with no timecode input?: Yes, by feeding the signal into one audio channel and letting the editing software read it from the waveform. It works reliably and costs you a channel that could have carried a safety audio track. On a two channel camera that is a real trade, and it is a large part of why cinema bodies with a dedicated timecode port are worth their premium.
How many timecode boxes do I need?: One per device that records, including every camera and every audio recorder. A box not attached to a device does nothing, which is why three-box kits are usually better value than buying singles. Some recorders and cinema cameras generate and output timecode themselves, in which case that unit becomes the master and needs no box of its own.
Is free waveform sync good enough?: For single camera work with takes of a few minutes, yes, and it is accurate. It becomes unreliable on long takes where clock drift accumulates, in noisy environments where the camera scratch track is poor, and on multi-camera shoots where everything must cut together across a whole day. Those three thresholds are where timecode starts paying for itself.

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