When you're a VFX artist and you've been looking at the same scenes for hours a day for weeks on end, constantly scrubbing back and forth across your timeline, you just become blind to errors and mistakes and technical glitches beyond the really obvious one.
You just need a second set of eyes or put down that specific part and look at it again later with fresh eyes.
No, I mean like physically how it happened lol. If the behind the scenes image is true, the position of the guy to the camera and the set just being a green screen... How did a reflection of the dude end up where it did? I would have assumed it to just be some kind of half developed afterimage on the film itself if not for the behind the scenes image.
This is a mistake that has apparently just been discovered this month, so answers are thin.
Here is the only decent one I could find:
"What appears to have happened here," u/itsjustmonty_ reports, "is that the camera traveled slightly too far and somehow no one noticed while cropping the footage." They include a string of uncompressed shots from the Blu-ray and a wild behind-the-scenes clip that shows a crew member off in the distance while filming the shot roughly 10 seconds in. In other posts, they reiterate that this was not their original discovery and they are simply reposting on Reddit to shed light on something that bubbled up from other corners of Star Wars fandom.
Regarding the real-life identity of Anakin's overlooker, an early suggestion was that it could be Nash Edgerton, Ewan McGregor's stunt double.
What's the verdict on this? Is it actually a human face that has accidentally snuck into this shot somehow, or is it just the lava and floating embers playing tricks on us? I can't really tell due to the color correction in this scene. Everything is just so orange.