Don't read if you want to stay amazed.
It's not a hologram as the people in the audience can't see anything, and it isn't a projection onto plastic like with tupac.
It's done by Rotoscoping (Cutting Freddie out of each frame) of the "these are the days of our lives" video and CGIing the torso to new legs.
The far away, back of the head and arm only shots (when they show the bongo player) are a double.
for example, If you look at the bit where Freddie raises his arm during the instrumental is, in fact, from just before and after he says “I still love you” at the end of the video, but they extend and make it fit the music by filming new footage with the stand in, quickly zoom into the bongo player and have the arm coming down dancing, and seeing him from behind and from far away.
The square on the ground is there to give the cameramen something to focus on, becuase the camera men can't see anything there.
Then they get the audience to play along whilst filming and get reaction shots from playing it back on the big screen.
It’s pieced together really well.
Next, they use a 'blue screen' to create the climatic lightsabre duel.
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And to understand why you only see Freddie from the back we have to remember that Freddie only filmed a lightsaber duel in 1983, so he would have a moustache and it would ruin the continuity.
In all seriousness the OP obviously doesn’t know much about editing and effects and wanted to know how it was done, was i too patronising?
Hi Medussa
I wasn't referring to those photos, which are obviously not Freddie. I was referring to the video trickery that is the topic of the thread. A clever piece of video technology which made it look like Freddie was actually performing with those other musicians. Freddie asked those left behind not to make him boring, so I don't think he would have minded this one bit. I'm reckon he would have liked the idea of a movie too, provided it was done well. And the jury is still out on that, as far as I'm concerned anyway.