How to use a clapperboard 101

Clapperboards are the key symbol of movie-making. They are symbolic, but they are also extremely useful, and an essential part of the filmmaking process on set. As a camera trainee, you need to know how it works. Let’s go through the basics.

The clapperboard is used to sync the camera and sound together (the video and audio files, which are recorded separately from each other), and provide important information about the shot: what scene it is, what specific shot in that scene, what take it is, what camera roll, and so on. We need it to identify quickly what each shot corresponds to in the script. If the director likes a particular shot, they can communicate that to the script supervisor, who makes notes for the editor. As a loader, you also need to take meticulous notes for each slate, writing down the lens, the T-Stop, any filters being used, shutter speed, frames per second, etc.  This information will then be copied to the camera reports, which you can to refer to in the future, in case you need to reshoot anything and need to recreate the shot exactly.

In the UK we start on slate 1 take 1 and go up in slates until the end of a block (e.g.. slate 826 take 3), then reset numbers at the beginning of block 2 (e.g. slate 1 take 1). Each slate corresponds to a different shot, meaning that if you change lenses or camera position, you would go up a slate. Let’s say for shot 1 you are on a 50mm lens looking at person A, then for shot 2 you are on the same lens looking at person B, you would then have to go up a slate for that second shot. If you are going again on the first shot, then you would be going up a take, as nothing would have changed and you’re just doing the same shot again.

You might have also seen or heard acronyms like AFS, P/U, MOS, VFX, 50FPS. Let’s go through these to give them more sense.

AFS, stands for After False Start. You would put these letters next to the take number after the board was shown to camera, clapped and action wasn’t called.

P/U stands for Pick Up, it means that you are picking up the shot from a certain line, which is not the usual starting point.

MOS means you are not syncing or recording sound, so for this you would show the board to the camera with the sticks already closed.

Notations such as VFX and 50FPS are added to signal that there is VFX in a shot e.g.. a green screen, or that we have changed frames per seconds from 25FPS to 50FPS. When you aren’t completely sure what is supposed to be on the slate, always double check with the script supervisor. They are in control of what they would like written on the board. It’s very important to communicate and collaborate efficiently with them.

Once you’ve marked up your board, you need to actually use it! Of course, you’ve guessed it, there’s a protocol there too. Remember, the rule is if you have a 25mm lens put your clapperboard 2.5ft away, if you are on a 50mm lens, go 5ft away. It’s better to be further away than too close. If you have a filter in, you can also check if the board is in the right place by looking at the reflection of the board in the filter: if you see the board in the reflection, the board is in the right place. If you are unsure, check the monitors and give yourself reference points. Once it’s marked up, leave the slate in your run-bag close by, until the first AD calls ‘turnover’. If you are working at a fast pace, keep it on your belt, but make sure both your hands are free to be able to work.

After the first AD has called ‘turnover’, the sound recordist will say ‘sound’s at speed’. This means that both the camera and the sound are recording. You then ‘call it’, meaning you say out loud the numbers that are on the slate, including any of the particulars. For example, you would say ‘17 take 2 AFS 50 Frames’. Then the focus puller will roll the camera and only when they say ‘Mark it’, would you clap your sticks together. Then leave immediately! If you have to do an end board, which means to slate at the end of a scene, you would call ‘end board’ when sound and camera rolls and at the end of the take, rush in and put the board upside down, sticks open, mark it when the focus puller tells you to, then flip the board back the right way up and call the numbers as such ’17 take 2 on the end’. 

If you are front boarding for two cameras with only one slate, you would says ’17 take 2 A and B mark’ or ’17 take 2 common mark/board’. If you are boarding them separately, assuming you are on A camera, you would call out ’17 take 2 A mark(er)’, clap the sticks together, and then turn to the second camera and say ‘B mark(er)’and clap the sticks together. On an end board with two separate boards, A cam loader would clap first and flip the board around calling ‘A mark(er)’ and then B cam would clap and call out the numbers ’17 take 2 B mark(er) on the end’.

Knowing the technicalities is great but you also need to be considerate about the board. Remember that it can be quite loud, so if you clap really hard right in front of an actor’s face, it might be distracting to them, especially during an emotional scene. To help, you would either clap the board softly (which is called ‘soft sticks’) or call out an end board. 

There are a few other reasons to use an end board: the shot might be extremely tricky for the focus puller, the frame or the location might be way too tight to get the board in front of the camera, and it’s easier to do it at the end. Sometimes you’re in a situation where the camera cuts before you can put the board in. In this case you would have to put an end ID board (or end ident) right after, in order to be able to identify the last take. For this, flip the board up side down in front of the camera with closed sticks until the focus puller cuts, and let the script supervisor know. The script supervisor keeps extremely precise logs on each shots, so I will say again that it is essential to collaborate and keep clear communication with them.

And lastly, be proud of your board! Keep it clean with big, neatly written numbers that you can easily read. It can get quite tricky and very stressful, but you got this! Like everything else, practice makes perfect 🎬