How was this effect done?

[Steven White]

Ryan Weiber is talented, and he does work at an FX house... I'm not sure which one though. He does not have a twin. Doing cloning effects is simple enough - you just shoot the video and mime out each part. You then use compositing software like Adobe After Effects (which Ryan used) and mask the characters such that they both appear.

If you want a physically moving camera, you need very repeatable camera work, and the pros do this with motion control. Ryan did it with a Lego train.

The mirror shot is simply accomplished with a little masking and some reversing and slowing of the footage, or exceptional miming skill.

Any direct interaction usually requires a third object. For handing off the coffee cup as an example, usually the cup is placed on an object like a stool or a chair. Film one side putting it down, the other side picking it up, line up the two in time and mask out the chair.

All that is really required is a little compositing know-how and a lot of patience.

-Steve

[Jim Rog]

Thanks Steven for all that great info