Pinhole cameraobscura

What very well might just be the

Fastest Pinhole CameraObscura Project Ever

Astound and bewilder your friends!

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

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!

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:

What You’ll Need

What You’ll Need

Fancy Tea Tinfrom B&N Cafe

Tissues

BlackPaper

What You Need

ScissorsRubber BandAluminum FoilPinsPokey ThingSharp KnifeWhite Paper(not shown)

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)

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

Inside of the Box Thus Far

Add the Viewing Window

• Flatten a tissue and...

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

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.

But wait!That’s not all!

Bonus Two-in-OnePinhole Camera Obscura

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.)

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:

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.

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