The helpless look gives Caesar pause. Here is a swordsman from straight out of a fantasy novel relying on him to get back home, even if it is to his death. Caesar can see the desperation in his eyes. As far as this elf is concerned, it's life or death that he gets back home.

So Caesar tries to think of anything that he could use to calibrate it on the fly. Something concrete. Something real. Something--

That is also a prototype, just like this machine. A scanner that used atomic structures and quantum theory and a bunch of other things that Caesar is pretty sure is only partially working. But it's worth a shop.

"... I have something I can try." Caesar moves again, going through a few boxes to try to find it. "It might not work, but I can try."