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Page 1: Pinhole cameraobscura

What very well might just be the

Fastest Pinhole CameraObscura Project Ever

Astound and bewilder your friends!

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An apologetic but fortunately brief note about readability:

We are so very sorry if this appears too small. To see this in full-screen mode:

• Click “view in Slideshare”-type button

• Click the “full” button

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Pinhole Camera Obscura?

Why, yes! Some smart person figured out that a simple pinhole will let you see a sharp (but inverted) scene on a transparent window or on the inside wall of a dark room.

Sure, it’s really dim, but everything’s in focus!

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Amazing! How can that be?

The pinhole is so small that each little piece of the viewing window receives light from just one part of the scene:

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What You’ll Need

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What You’ll Need

Fancy Tea Tinfrom B&N Cafe

Tissues

BlackPaper

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What You Need

ScissorsRubber BandAluminum FoilPinsPokey ThingSharp KnifeWhite Paper(not shown)

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Let the Craziness Begin!

• Cut a small (1 cm x 1 cm) square of metal out of the bottom of the tea tin

• (Be careful)

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Make the Pinhole

• Tape some flat, taut aluminum foil over the hole

• Poke a tiny hole in it.• Make magazine says

between 0.2 and 0.5 mm works well.

• I know it’s tricky, but try to prevent excess material jutting out from either face of the foil. That’ll mess up the image.

AstoundingPinhole

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Inside of the Box Thus Far

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Add the Viewing Window

• Flatten a tissue and...

• Secure it to the top of the tea tin using a rubber band

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Try that Bad Boy Out

Hold it up to some lights – but not the sun!Or, turn out the lights and hold it near a candle flame.

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But wait!That’s not all!

Bonus Two-in-OnePinhole Camera Obscura

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For a Brighter Image: Baffles!

• Remove that stupid tissue• Fold the black paper so that it lines three inner walls• Cover the fourth wall with white paper• View scenes at an angle - but it’ll be easier to see.• (Ok, it’s still dim, but you should see lamp filaments.)

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For a Brighter Image: Baffles!

• Remove that stupid tissue• Fold the black paper so that it lines three inner walls• Cover the fourth wall with white paper• View scenes at an angle - but it’ll be easier to see.• (Ok, it’s still dim, but you should see lamp filaments.)

Angle it downso the light

hits the bottominner wall:

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Parting Thoughts

• Still too dim? Yeah, I know. But it got you thinking about optics.

• Try viewing the sun (indirectly). Its image will be small, but an eclipse should look like a crescent.

• Bigger images: use a longer tube• Want to make an actual camera, with film? See:

Ross Orr, “Pinhole Panoramic Camera,” Make vol. 09, pp. 92-103.

• Want to learn something about optics? Try:– Donald O’Shea, Elements of Modern Optical Design– Hecht et al, Optics

• Wish you had those 15 minutes back? I dunno, try making some of that tea.

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Thank you.Gregg Favaloraan engineer near Bostonwho worked for many years on 3-D televisionand is now employed at Optics for Hire

www.greggandjenny.com/gregg