Three of the main characters were the same actor, and yet there are shots with all of them in the same scene. When I saw this as a young adult I didn't even notice that Mike Myers was playing three roles and was genuinely dumbfounded years later when I found out.
Assuming it's not just using body doubles which is the easiest way, usually you film the same actor twice with the camera left in place and then splice the two films together either by physically cutting and pasting the film or more recently with software. The software also has the advantage that it can blend things better, and fix lighting differences, and differences in film exposure which isn't as big of an issue now with film quality being more consistent. Often in older films you can often see an obvious difference between the two shots.
There's also some films where they take a much easier approach where they film one scene and then use a green screen for the second take. This allows for doing the takes at different times since the camera might get moved or other small changes that are difficult to work around in a single day and allows for multiple camera angles to be used more easily, but it can be difficult to get the aspect ratios and depth just right, so it often looks less natural if the first take has the character along the same or too similar of a plane of depth as the second.
Compositing has been a thing for, like, forever, going from cutting and gluing film together to, well, having lookalike instead of the real actor in certain shots...
I'm mostly weirded by how you found out only now. I guess go and have fun looking up "Captain Disillusion" youtube channel.
I love Captain D, the way he takes apart a scene in Blender is an art form in itself.
I guess the question I'm asking is, normally when editing comes into play you can sort of notice it through one way or another. There's an uncannyness to it that makes it jarring, whereas in Austin Powers I never once clocked on that I was watching the same person. Did they use really sophisticated techniques for this? Was the campiness and comedic tone of the film itself a good distraction from any editing goofs?
If it was a more sombre film, would I notice it more I wonder?
Edit: @Aurenkin mentions the ping-pong scene in the 2019 Moon film, which has a more mature tone and the editing there was definitely flawless.
Here's a Captain Disillusion VFXcool episode about this special effect, specifically as applied to Back to the Future (which innovated having a split screen with a moving camera): https://www.youtube.com/watch?v=rhNDsPMaK_A
I personally have never noticed flaws when such tecniques are employed, but it may be just immersion doing its job. I've never heard of Austin Power being singled out for its special effects...
Red Dwarf was doing same actor multiple roles for a long long time. There are many episodes to check out, but one of the best examples is Stasis Leak (3 of each character on screen), another good example is Me2 (Rimmer and Rimmer). They were doing this in 1988.
they could film the actor in different costumes on the same set without moving the camera, and then they put those performances together.
so you can have the profile of Austin powers on the left talking to the profile of Dr. evil on the right, and those were separate performances pasted together so it looks like they're responding to each other even though Mike Myers was performing those conversations separately during different recordings.
If evil and Austin are in the same shot and it's an over-the-shoulder, the actor facing the camera is the real actor and the guy not facing the camera is a body double with the same hair or bald mask
so if you were looking at Austin and Dr. evil in the same shot, either those are two separate performances put together and you'll see that they never touch each other, or if they do touch each other, you'll notice that you never see the frontal face of one of the actors, which is actually a body double.
and you can see these two techniques and others used in Eddie Murphy's movies, or pretty much any body double move movie.
Fuck I didn't mean freaky Friday meant that twin one The parent trap fuck. Well. Now I need to do a shot for shot remake edit where Jamie Lee Curtis plays both
I'm not putting anyone down, but I am genuinely amazed that this many people were unaware. If you asked me how many people who watched weren't aware, I'd have guessed like less than .01%.
Orphan Black was great. The most insane part was how you could tell which character was pretending to be another character even though they look the same. Tatiana Maslany did fantastic work on that show.
My dad and uncles made home videos on a 8mm camera doing this trick when they were teenagers, so it must be pretty easy even without a computer.
One thing I know is if the background doesn't change, you can basically film one character's part in the scene, then re-expose the film to do the next character's and so on.