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Engineering in Service of a Dark Art

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Engineering in Service of a Dark Art

Engineering in Service of a Dark Art

Engineering in Service of a Dark Art

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript

Biology graduate student Tom McDonagh, of Rockefeller University, likes working with light. For his Ph.D. he built a spinning microscope that uses centrifugal force to test the gripping power of different molecules. McDonagh also innovates with light outside the lab, in tech-savvy shadow puppet plays.


Flora Lichtman is here with our Video Pick of the Week. Hi, Flora.


Hi, Ira.

FLATOW: We've got something very interesting, as always.

LICHTMAN: Yes. We're going into the shadows for this week's video pick. That's pun-tastic because it's actually we are doing a video about shadow puppets and shining a light on innovator Tom McDonagh.


LICHTMAN: So he is a biologist at Rockefeller University, a grad student. And, you know, by day he's making microscopes and doing that kind of experimenting but he's also really into shadow puppet theater and is doing really neat things with casting shadows. And you might think, you know, this seems really simple. How could you possibly innovate there? But he has found ways.

For example, he's using laser cutting and 3-D printing to make the puppets. He's got a mobile light source so he can do sort of cinematography on the fly, panning and zooming by moving the light source around. And the coolest thing that he's working on is making 3-D shadows.

FLATOW: 3-D shadows on SCIENCE FRIDAY from NPR. So 2-D shadow, flat shadows are not good enough for him.


LICHTMAN: Well, you know, this is the...

FLATOW: Why, everything in movies is 3-D now, right? Right?

LICHTMAN: That's right. That's right. Why should this be any different?

FLATOW: That's right. It has to be 3-D in a movie and he's going to take the shadow puppets and make them 3-D.

LICHTMAN: And it's the same principle at work, so what he does is he has two lights and they look almost sort of like a set of goggles. And each light - so they're a few inches apart.

FLATOW: Mm-hmm.

LICHTMAN: And each light puts out a different sort of polarized light. And then you shine that at, you know, your object that you're creating the shadow from and if you sit on the other side of the screen, this sort of special screen, wearing your movie theater 3-D glasses, you actually see 3-D shadows.

Now, it's very hard to translate that on a Web video and I apologize. SCIENCE FRIDAY listeners, I really spent a long time thinking about this and if this were possible, but you can see Tom perform this if you happen to be in Pennsylvania. He's performing next week and we have the details of how you could go see him do this.

FLATOW: Yeah. Yeah.

LICHTMAN: In person.

FLATOW: It's up on our website. It's It's 3-D shadows and it's quite beautiful. You've mixed the music very nicely with it, tell a great story. And there is a real story you tell in there.

LICHTMAN: Yeah. So Tom got interested in this, this true story of these two - this odd couple, basically. It's this American doctor and this French inventor and kind of ballooning pioneer. And it's 1785 and they make the first trip across the English Channel by air. And they do it in a hydrogen balloon. But he said that, you know, neither of them really knew that much about ballooning. No one really knew that much about ballooning. And so they get about halfway across and the balloon starts to descend.

FLATOW: I hate it when that happens.



LICHTMAN: Yeah, you bet you. So they're going across and they have to get - to get to France, they have to go over these cliffs. And so they have to keep throwing stuff out of the balloon, so all of the scientific instruments. He said - I don't know if this is true, maybe our listeners will know - that they actually had to take off their clothes, they were so desperate.



LICHTMAN: Yeah. Totally. To lighten the load. Anyway, they made it. So it's a great story and he's translated it really beautifully...

FLATOW: Yeah. Yeah.

LICHTMAN: this work.

FLATOW: And if you want to see how he did it, how he actually created the 2-D version - you have to create the story, right?

LICHTMAN: That's right.

FLATOW: He creates the cutouts and the puppets.


FLATOW: And you can see the puppeteers doing the whole thing with the balloon going up and down.

LICHTMAN: It's very intricate. And it gave me something - you know, if you ever were into shadow puppetry as a kid or whatever, this is taking it to the next level. I mean this is really, like, geeking it out to the next level. You can take a saucepan and put your sharp halogen light in it and that really does a lot if you want sharp shadows. Anyway, I don't - something to do this weekend.

FLATOW: This is a project you can try at home. Now, making it 3-D, I'm not sure (unintelligible) going to be that easy, right?

LICHTMAN: It's not quite as easy but it's not impossible.


LICHTMAN: You know, you get these two types of polarizing lights and the special screen and you too can do it. There are videos on the Internet about this. I've watched them.

FLATOW: All right. It's up there on our Video Pick of the Week. How you make a 2-D shadow movie into a 3-D shadow movie. And because that's what it is, 3-D. And it's beautifully made by...

LICHTMAN: (Unintelligible) it's in.

FLATOW: ...Flora Lichtman. Thank you, Flora.

LICHTMAN: Thanks, Ira.

FLATOW: That's about all the time that we have for today.

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