How do cameras collect collect
images and place them on film? They do it with lenses made of highly polished
and precisely shaped glass. But did you know that you could actually create
an image with nothing more than a pinhole? Try it by making a device called
a pinhole camera. Pinhole cameras are very easy to make.
- A large coffee
can with lid or oatmeal container
- A good-sized nail
(at least 3" long) and a hammer
- A small pin or
needle
- One 3" x
5" index card
- Tissue or waxed
paper
- Tape
- Dark cloth, about
1 X 1 meters
Use the hammer and nail to punch a hole in the bottom of the container.
Try to place the hole in the center of the bottom. Next, tape the 3"
x 5" card on the bottom of the can. Using a pin, punch a small hole
in the card right through the nail hole. The cleaner the hole, the better
the image. Put on the plastic lid, and you have completed your camera.
If you don't have a plastic lid, tape a sheet of tissue paper or waxed
paper over the end. This will become your screen.
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It's now time to try out your new camera. Start with something easy like
a bright light bulb. Point the pinhole end of the camera about 1/2 meter
from the lit bulb while looking at the other end of the camera. You should
see the image of the bulb projected on the surface of the lid. Do you notice
that the bulb is upside down?
Now it's time to test your camera on something outside. To collect enough
light to make the image bright enough on the screen, you need to look
at something in full sun. Aim your camera at a brightly lit car or tree.
To make the screen dark enough, place the black cloth over your head and
the top of the camera. (Have you ever seen those old photographs of the
photographers with the black cloth over their heads? Now you know why.)
With a little adjusting, you should see the image inverted on the screen-and
in color!
For the more adventurous,
see what happens when your pinhole camera has two holes rather than one.
Before you try, guess what you think will happen.
The only thing your
camera doesn't do is capture the image on photographic film or digitize
the image on a disk. Until you can come up with a way of loading your
film in your pinhole camera, you will just have to use the ultimate in
recording – your memory!
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