The stop-motion musical had 24 frames to a second, meaning they had to pose characters 24 times for each second of the completed film.
That consisted of roughly 110,000 frames.
One minute of the movie required an entire week of filming.
And the movie therefore took more than three years to complete.
There are as many as 60 individual characters, with three or four duplicates each.
Each puppet had an armature inside it, enabling flexible movement.
The sculpture department consisted of only four people.
More than 400 distinctly different Jack Skellington heads were used.
And Sally had a mask for every expression change.
To make Jack blink, replacement series were wedged into his eyes, which took up three frames per blink.
Set designer Gregg Olsson built a quarter-scale mock-up of Halloween Town as a model for the real set.
The set also had trapdoors so animators could pop up and do the animation from beneath.
Although the sets were built in miniature, they were lit as if they were full-size movie sets.
Many of the sets required as many as 20-30 lights to create dramatic effects.
If there was ever a problem with a frame, they would have to go back and re-photograph the entire thing.
Composer and lyricist Danny Elfman didn't have a script to write the songs from.
The entire production required 13 animators.
It also included over 100 specially trained camera operators, puppet makers, set builders, and prop makers.
There was a total of eight camera crews.
And 19 sound stages with 230 sets total.
Basically, the talent and dedication required for this movie is severely underrated.
You can watch the full video on the making of The Nightmare Before Christmas here.