Episodes of the "Sweeney" and the like were all assembled this way - with the Sweeney - programmes were assembled using the previous days shoot rushes which would be processed overnight and would be delivered to Colet Court fresh in the morning.
I was quite surprised to learn that the Film Editors on The Sweeney also had the job of choosing which library music went with each sequence.
I also found this 1970s training film about the correct use of clapperboards in post production. I hadn't understood why end boards were used until I saw this, although I remember news crews using end boards attached to the sound recordists portable gear.
A training film for Clapper Boards.... blimey.
They are still used these days - more so for scene information as Camera and Sound use timecode and is therefore very easy to sych.
There are numerous sizes of board - the small ones generally used for closeups, the medium which is mostly used, and I've seen ones at about 6feet square used for long shots. But not seen one of those for years.
They will also include information about Lense / Interior / Exterior - as well as some include a Greyscale and Colour reference - this was used by the Labs when processing the film.
Again - today - most cameras have all this stuff available.
When I started at Central - documentaries and schools programmes were still being made on Super 16mm film. (the single Perf stuff)
The sound recorders (1/4" tape with Nagra machines) had a link to the camera.
The camera when running at speed would output a continuous pulse, this pulse was received by the Sound recorder on another track - this kept the two locked together.
When the camera rolls, the operator presses a button which "fogs" (over exposes) one frame of film, and at the same time records a "blip" onto the sound tape.
So - in editing, there are two reference points to synch it all.
This is what they call Crystal Lock.
The only issue is - 1/4" tape stretches, so once recorded and entire sound reel needs to be transferred to magnetic film for editing.
You'll also see Clapperboards with a digital readout on the bottom - generally used with Music Videos (how these are shot is another topic on it's own).
The digital readout is an SMPTE Timecode which is common to the clapperboard, camera and sound recorder.
New versions of this also now include Frame META data; so individual frames can be matched to individual bits of soundtrack.
This setup is really useful when you are using more than one camera (ie on a large stunt - with multiple angles)
If a clapper is held open - without a snap, this indicates that sound isn't being recorded.
If a clapper is held upside down - that's called an "end board" - normally common place in News and Documentary making when you can't predict what's going to happen, so the camera operator just rolls film to grab the action.
A lot of productions have a clapper made up, and this usually ends up in the hands of the Director at the end of the shoot.
Sweeney had there's made up.
Sammies equipment hire place in Crickelwood had most of the ones from the Bond films on the walls in their reception.
Also - they are usually perspex and they use dry wipe markers.
Not seen a chalk one for years!
Sorry it's long winded, not an easy way to explain why they use all this kit!