Coverage of UK election nights is usually interspersed with footage of ballot counts, along with the result declarations in individual constituencies. The image below shows an example of one of these counts, and you can see that there are a lot of people seemingly milling around, especially in the back of the hall.
Picture Source: Edinburgh Live
Who can attend these ballot counts, and who is allowed to actually count the ballots? Do you have to sign up to be a volunteer, do you have to be a member of a constituency political party, or can you just turn up on the night?