This is a great shot that involves leading our actor as she runs through her house, up the stairs, ending in the bathroom for a surprise effects ending.
The shot was filmed normally and flipped in post to achieve the mirror image. The actual bathroom mirror was replaced with a bluescreen into which the original shot was superimposed.
Operator's Commentary Quote from Carin-Anne Strohmaier, 1st Asst Film Editor
I'm so glad so many liked this shot - this was one of Bob Z's favorite in the show. Having had to do the counts for this optical to Sony Pictures Imageworks (who deserve the credit for the final look) this was how it was done - a Steadicam person with the Vista Vision camera strapped to his chest ran backwards in front of Young Ellie as he goes up the stairs and down the hallway - there was a speed change - we ramp from 24 to 48fps (though I can't remember exactly - we could have ramped through three different speeds) - by the time she stops and puts her hand to open the medicine cabinet door ("A" plate ) - we are then inside the reflection. The medicine cabinet was the "B" plate (second plate) and then the door closes and we have the "C" plate (third plate) which was the reflection of the photo of Young Ellie and her dad. By the way - the first time we received this CGI shot as a final (completed & ready to be signed off) Bob Z noticed that the picture frame did not match the one in the Arecibo Puerto Rico bedroom with older Ellie and Joss so they had to have an insert crew reshoot the "C" plate with the correct picture frame and re-composite the shot over again - not an easy thing to do since timing was critical in getting everything to match up. I also liked to give our Avid assistant, Orlando Duenas, credit since he did the initial line up of the shots in our cutting room which Sony Imageworks used as a guide.