Maybe I am missing the obvious, but what would the Muppet stage(s) look like from behind the scenes? I understand the Muppeteers operated the Muppets from below the stage. As such, there must be ruts or completely open spaces to give the Muppets free range in many scenes without guest stars (and few to no props). On the other hand, there must be a second stage with ruts cut in strategic places for Muppets to move around within while interacting with the guest stars; yet, the guest stars are still standing on solid flooring in places. Does anyone know the finer details how the original Muppet show worked the stage(s)?
There are probably multiple answers specific to different set pieces.
Some often reused set pieces, like the guest’s dressing room were probably built to be adaptable with removable/replaceable sections of the floor (solid floor to accommodate guest stars, empty cut-outs to accommodate puppeteers).
Here are some behind the scenes photos that show the puppeteers’ placement within the set pieces.
Here are some that show muppet and guest star interactions:
Kermit with John Cleese
Kermit with Linda Ronstadt
Sam the Eagle with Spike Milligan
Every set will be built for rostrum to slide in and out as appropriate. It looks like it may be a bit precarious for the actors to watch their step, but I’m sure it’s no different to when they have to step on marks in regular shoots.
That Linda Ronstadt image is probably the best way to demonstrate that. Here’s another showing how they squeeze themselves into tight spaces.
There are scenes wherein the muppets are shown head-to-foot sitting (ex: G-Grover… G-George.) That’s harder to pull off, even though the legs are immobile.
I’m stumped with Bert’s “Doing the Pigeon” number. I think scenes wherein he sings and gesticulates with his hands, he has immobile legs. Shots showing his legs dancing are done using a different set of muppet parts.
It’s also the best way to demonstrate how awesome it could sometimes be to be a puppeteer.
Mmmmmmm, face at 1970s Linda Ronstadt crotch level…
One muppeteer for every two muppets! So that’s how they do a crowd!
Those sequences are usually done in front of black velvet drapes, with muppeteers also dressed entirely in black, so they can operate the feet in the same way they do the arms, but usually while standing up instead of awkward crouching. They can then sometimes key out the black for a full colour background.
How can they key out the black when the puppets themselves contain black parts (such as, in the example you linked to, Kermit and Fozzie’s pupils)? Wouldn’t they use a bluescreen instead?
I understand one of the actors on “ALF” was injured by falling into or tripping over one of the voids in the floor that the ALF puppeteer used.
They might, they would today (greenscreen, unless it was Kermit), but I know they used black for the Fieries sequence in Labyrinth, which subsequently looked a bit crap around the edges. Black is traditional in puppetry.