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Frostbite Theater

Here's a Question! - Small Pinhole vs. Large Pinhole

The image of a lightbulb is projected onto the back of a pinhole camera. A pencil is used to make the hole larger. What happens to the image?

Announcer: Frostbite Theater presents... Cold Cuts! No baloney!

Joanna and Steve: Just science!

Joanna: Hi! I'm Joanna!

Steve: And I'm Steve!

Joanna: Here's a question for you...

Steve: The image of a lightbulb is projected onto the back of a pinhole camera.

Joanna: A pencil is used to make the hole larger.

Steve: What happens to the image?

Joanna: Does it become dimmer and sharper?

Steve: Does it become brighter and sharper?

Joanna: Does it become dimmer and blurrier?

Steve: Or, does it become brighter and blurrier?

Joanna: Pause the video now if you'd like to think it over before we show you what happens.

Steve: Since the pinhole is larger, more light gets in, so the image is brighter.

Joanna: The image is also blurrier because the larger pinhole is less restrictive. It's easier for light coming from different directions to hit the same spot on the image.

Steve: This is why you don't see images of the outside world projected on the walls of a typical room. Windows are too big. The images they make are so blurry there isn't a discernible image at all.

Joanna: Thanks for watching. I hope you'll join us again soon for another question!

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