How to Make a Pinhole Camera

Did you know that the visual image you see is upside down and inverted left to right? This is because the opening that lets light into your eye (the pupil) is very small and light can only travel in a straight line. Because light travels in a straight line, the top of an image is reflected to the bottom of your retina in the back of your eye and the bottom of the image is reflected to the top of your retina. The result is that the image on your retina is upside down (and what is left is right and vice versa). You might ask why we don’t see the world upside down and the answer is that your brain makes the image right-side up. A pinhole camera works on the same principle as how light enters your eye. If you want to see for yourself what the image on your retina looks like it is easy to make a homemade pinhole camera.

Here is what you need: An empty Pringles can, a marker, a ruler, an X-Acto knife (or utility knife), masking tape, a thumbtack, a piece of aluminum foil, and a piece of wax paper. Most of these things can be found around your house. If you don’t have one or more of these things available, it won’t cost much to buy them. The cool thing with this project is that you get to eat potato chips and do a nifty science demonstration.

Step 1: Take the lid from the empty Pringles can and punch a hole in the middle of it with the thumbtack. Then punch a hole in the metal bottom of the can. Put the lid aside.

Step 2: Draw a line around the can about two inches from the bottom. Take your X-Acto knife and cut along the line so the tube is in two pieces.

Step 3: Take the wax paper and cover the small piece of the can (the wax paper acts like a screen). Fold the wax paper over the edge and tape it to the can with the masking tape.

Step 4: Put the big piece of the can next to the small piece and tape them together. Next, take your aluminum foil and wrap it around the entire can twice (to keep light out of the tube) and then tape it to the can. Put the plastic lid back on the can. You are done!

Step 5: Go outside, close one eye, and hold the can up to your other eye. Look through the lid. You will see the image in your backyard upside down. The top of your trees will be at the bottom of the wax paper and the bottom of the trees will be at the top of it! (Note: you can only look through the Pringles can. You can’t actually take pictures like a real camera.)

For a pictorial demonstration, check out the website at www.exploratorium.edu/science_explorer/pringles_pinhole.html. The steps I listed are slightly different but that’s what worked for me when I made the Pringles can pinhole camera I show my students.