Tips for Second ACs: Proper Slating Technique



One of the more often overlooked production steps, especially in the digital age, is proper slating technique. It is easy to understand why: banging a slate seems to belong to a bygone era, something relevant only to productions shooting on film, and in today’s rapid-fire production environment with directors rolling endlessly on multiple takes or wanting to shoot without alerting the actors that they are being recorded, slating has become something seen as more of a hindrance than a help.

"The primary purpose of slating is to identify individual takes, so that every time the camera starts and stops, there is an identification for the editor."

The truth is that slating is a valuable production step that can save you time and frustration in editing, and the time and attention paid to proper slating technique can help bring order to the chaos of your production.

The primary purpose of slating is to identify individual takes, so that every time the camera starts and stops, the editor has an ID tag for the footage. Now, with virtually everyone having a non-linear editingsystem (NLE) at home, or on their laptop or tablet, this may seem unimportant. However, with the advent of digital video, the amount of footage recorded and then sent to post production for viewing and editing has grown to almost unmanageable proportions, limiting the amount of time an editor has to view and evaluate the footage. Providing  your editors with at least a quick identification, so they can know which shots to ignore and which ones the director feels are worthy of using, makes a huge, positive impact on the editing process.

Proper slating encompasses collaboration among three people―the clapper (the person handling the slate), the continuity person, and the editor. The editor is the person who sets the numbering system that the clapper follows, so it is important to confirm the system they want to follow. The continuity person keeps notes on each shot, the number of takes of each shot, and what the action in the frame was during each take. The clapper usually writes camera notes on each take, and puts the slate into the frame.

Breaking it down

The face of the slate will normally contain the following information: Production name, Director name, and Cameraman name, all of which normally do not change during the production. There will also be larger spaces for scene, shot, take, and sound. Then there’s additional information such as date, Mos/Sync, Day/Night, Interior/Exterior, filters used.

Now, what the scene is should be obvious; the script has been broken down into a number of individual scenes, which have been numbered before shooting begins. The shot number represents the order in which you are shooting the scenes. The first shot is commonly labeled with the scene number, and then the next position from which the camera shoots―add an A to the end, and then a B, C, D, all the way to Z, usually skipping the letters I, O, and S, as they can be confusing when placed next to Scene numbers. It is important that every time one changes the camera position this includes the same position but, with a different lens, one should change the shot number, as well. Then there is the take―this is a number that rises incrementally until you move to a new shot, at which point the take number should be reset.  For example: Scene 32, shot A, take 1, take 2, take 3; Scene 32, shot B (often condensed as 32A, 32B, 32C, etc) take 1, take 2, take 3, etc. Some slates have a space for sound numbers, as well. It should be noted that the convention is that sound numbers don’t reset, but continue, so the slate would look like

Scene 32A, Take 1, Sound 45, Take 2, sound 46, Take 3, Sound 47; Scene 32B, Take 1, Sound 48, etc.

Now that you understand the basics of how slate numbering works, it is time to go over basic slate techniques.  There are a various types of slates. There is the standard slate, which usually has a set of black and white (or color) clap sticks that are banged together to provide a sync point for picture and audio. Insert slates that are smaller versions of the basic slate do not have clap sticks, and are used for tight shots, such as product shots, or extreme close-ups. On the opposite end of the spectrum are opera sticks, which are about 6 feet long, and contain no clapboard―they are intended to provide sync points for extremely wide shots.

There are timecode slates, as well, which display the timecode from either a camera or audio device, giving you a visual readout of the timecode that is being recorded, as well the scene information. These slates almost always feature clap sticks, as well as the timecode display. Similar to timecode slates are time of day slates. Time of day slates are most useful for multiple camera shoots, as they provide a visual reference for syncing the cameras in post.


In its most basic form, the slate process works like this: Audio recorders and cameras must all be recording at speed. Traditionally, when working with an external audio recorder, you start that first, the clapper or 2nd Camera Assistant, handling the slate, waits for confirmation of speed and then audibly reads the slate. After the video devices are started, the 2nd Camera Assistant shows the slate, and then claps the sticks. It is important that the 2nd Camera Assistant holds the slate steady and unmoving―remember, the editor is going to be reading the slate. Traditionally, one lets the clap sticks close. Pause a beat, and then move out of the way.  

Proper execution of the slate procedure is much trickier than it seems. On large-scale productions the slate is handled this way: the First Assistant Director says, “Roll camera,” and both the sound mixer (the recordist) and the camera operator start their devices. Then the 2nd Camera Assistant (British term is Clapper/Loader) places the slate within the frame at the distance from the camera explained later. The 1st Assistant Camera (British term: Focus Puller) adjusts the focus. The proper distance and focus is so the slate fills the frame and, thus, all the information is readable. We call this being “Suitable for Framing.” On large productions, the mixer has already identified the take in their audio track. Thus, the 2nd Assistant only has to say, “Marker!” followed by the actual snap of the clap sticks. Saying just “Marker” rather than the full audio identification saves time and confusion at a high stress moment. Note: it is imperative that the person slating be absolutely certain that both the audio recorder and the camera are at speed. If either is not, and the slate is clapped and removed, the procedure is worthless and must be repeated. This back-up procedure is known as “Second Sticks” and is always called for in aggravated tones by the camera operator or mixer. The ignominy of doing a second sticks is to be avoided at all costs, for it makes the camera crew look unprofessional, as well as  wasting time and actor performances.

Head Slate: This is a slate that is recorded at the beginning of the shot.

Tail Slate: This is used when there is no capability of slating at the head of the shot. It is important that all devices continue to run after the director calls cut, until the tail slate is complete. When tail-slating, one inserts the slate into the shot upside down, and bangs the sticks together. Then one flips the slate over so that it is easily readable, and then calls out the information, then the cameras and audio recorders stop. The upside-down slate tells the editor that the slate is for the previous shot.

Holding the slate: One should tilt the slate slightly forward. The reason for this is that lights will often reflect from a slate into the camera lens, creating glare that renders the slate unreadable. Tilting the slate slightly forward will bounce reflected light down, away from the camera lens.

Banging the Sticks: The banging of the sticks provides a visual and audible cue point. Do not slam the sticks together, just the sound of them closing naturally will provide a loud enough sound under normal conditions, although in noisy environments, one may have to really bang the sticks. Something else to consider is the effect of the slate on the actors. Loud noises can throw an actor off as while preparing for a scene. There is nothing worse than watching your footage and seeing the actor break out of character because the clap sticks were slammed close to them. So, when slating near an actor, it is best that one does what is known as “soft sticks,” which means one gently closes the sticks to avoid disturbing the actor.

Flipping the sticks: Most clappers hold the slate so that the hinge of the sticks is closest to them. This allows them to hold the slate, and clap the sticks using only one hand. Sometimes you will not be able to do this, but a well-made slate is designed so that the sticks can be removed and flipped so the hinge is on the opposite side, just for such occasions.

MOS: There are a variety of methods used to alert the editor to the fact that the shot being slated is M.O.S. No one knows the origin of the term; Mitt Out Sound is supposedly derived from a German director’s mispronunciation of "Without Sound. Other explanations are Minus Optical Stripe, Motor out of Synch, Mixer off Set, etc., indicating that audio is not being recorded with this shot. 

One technique is to shoot the slate with the sticks closed. Some clappers prefer to shoot the MOS slates with the sticks completely open. Still other clappers will put one of their hands in between the clap sticks, as if the sticks are closing on their hands.

Another  technique is to record a few frames of the slate with the term SER (Series), which means that all the shots that follow are just the same action being done over and over again, and there is no dialog, so it isn’t efficient to stop and re-slate. This technique is most often used when shooting quick inserts.

Where to put the slate

The general rule of thumb is to place the slate directly in front of the lens, and then move it away from the lens 1 foot for every 10mm of lens. So if there is a 50mm lens on the camera, place the slate about five feet away from the front of the lens. This rule of thumb is based on 35mm motion picture cameras, so one may have to make some adjustments when using cameras with different-sized sensors, but with a little practice it will become second nature.

While it may seem that slating will slow down a production, with practical application, one will be able to recognize the overall benefits slating brings to productions.


I do a lot of editing work for first-time filmmakers and one of the very important questions I ask at the beginning of any enquiry for my services is "Did you use a slate/clapboard while shooting?". If they say yes, I heave a silent sigh of relief... if not, I know that I need to multiply the time required to do the job by at least 5. An invaluable tool of the trade, it is often ignored by first-timers. A lot of them think it is enough to log takes on paper, not taking into account the job-requirements for the editor.

Very interesting piece specially in this digital age where some very "ancient" but useful techniques are often ignored.

Would love to see sample of script breakdown page in scene N°s and continuity record of shots coverage on script page.

I think it might add a little more to the substance of the article